<!DOCTYPE book PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
- "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd"
+ "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd"
[<!ENTITY mdash "—">]>
<!--
- Copyright (C) 2004-2014 Internet Systems Consortium, Inc. ("ISC")
<title>Scope of Document</title>
<para>
- The Berkeley Internet Name Domain
-
(<acronym>BIND</acronym>) implements a
- domain name server for a number of operating systems. This
- document provides basic information about the installation and
-
care of the Internet Systems Consortium (<acronym>ISC</acronym>)
-
<acronym>BIND</acronym> version 9 software package for
- system administrators.
+ The Berkeley Internet Name Domain
+ (<acronym>BIND</acronym>) implements a
+ domain name server for a number of operating systems. This
+ document provides basic information about the installation and
+ care of the Internet Systems Consortium (<acronym>ISC</acronym>)
+ <acronym>BIND</acronym> version 9 software package for
+ system administrators.
</para>
<para>
- This version of the manual corresponds to BIND version 9.9.
+ This version of the manual corresponds to BIND version 9.9.
</para>
</sect1>
<sect1>
<title>Organization of This Document</title>
<para>
- In this document, <emphasis>Chapter 1</emphasis> introduces
-
the basic <acronym>DNS</acronym> and <acronym>BIND</acronym> concepts. <emphasis>Chapter 2</emphasis>
-
describes resource requirements for running <acronym>BIND</acronym> in various
- environments. Information in <emphasis>Chapter 3</emphasis> is
- <emphasis>task-oriented</emphasis> in its presentation and is
- organized functionally, to aid in the process of installing the
-
<acronym>BIND</acronym> 9 software. The task-oriented
- section is followed by
- <emphasis>Chapter 4</emphasis>, which contains more advanced
- concepts that the system administrator may need for implementing
- certain options. <emphasis>Chapter 5</emphasis>
-
describes the <acronym>BIND</acronym> 9 lightweight
- resolver. The contents of <emphasis>Chapter 6</emphasis> are
- organized as in a reference manual to aid in the ongoing
- maintenance of the software. <emphasis>Chapter 7</emphasis> addresses
- security considerations, and
- <emphasis>Chapter 8</emphasis> contains troubleshooting help. The
- main body of the document is followed by several
- <emphasis>appendices</emphasis> which contain useful reference
- information, such as a <emphasis>bibliography</emphasis> and
-
historic information related to <acronym>BIND</acronym>
- and the Domain Name
- System.
+ In this document, <emphasis>Chapter 1</emphasis> introduces
+ the basic <acronym>DNS</acronym> and <acronym>BIND</acronym> concepts. <emphasis>Chapter 2</emphasis>
+ describes resource requirements for running <acronym>BIND</acronym> in various
+ environments. Information in <emphasis>Chapter 3</emphasis> is
+ <emphasis>task-oriented</emphasis> in its presentation and is
+ organized functionally, to aid in the process of installing the
+ <acronym>BIND</acronym> 9 software. The task-oriented
+ section is followed by
+ <emphasis>Chapter 4</emphasis>, which contains more advanced
+ concepts that the system administrator may need for implementing
+ certain options. <emphasis>Chapter 5</emphasis>
+ describes the <acronym>BIND</acronym> 9 lightweight
+ resolver. The contents of <emphasis>Chapter 6</emphasis> are
+ organized as in a reference manual to aid in the ongoing
+ maintenance of the software. <emphasis>Chapter 7</emphasis> addresses
+ security considerations, and
+ <emphasis>Chapter 8</emphasis> contains troubleshooting help. The
+ main body of the document is followed by several
+ <emphasis>appendices</emphasis> which contain useful reference
+ information, such as a <emphasis>bibliography</emphasis> and
+ historic information related to <acronym>BIND</acronym>
+ and the Domain Name
+ System.
</para>
</sect1>
<sect1>
<title>Conventions Used in This Document</title>
<para>
- In this document, we use the following general typographic
- conventions:
+ In this document, we use the following general typographic
+ conventions:
</para>
<informaltable>
- <tgroup cols="2">
- <colspec colname="1" colnum="1" colwidth="3.000in"/>
- <colspec colname="2" colnum="2" colwidth="2.625in"/>
- <tbody>
- <row>
- <entry colname="1">
- <emphasis>To describe:</emphasis>
- </para>
- </entry>
- <entry colname="2">
- <emphasis>We use the style:</emphasis>
- </para>
- </entry>
- </row>
- <row>
- <entry colname="1">
- a pathname, filename, URL, hostname,
- mailing list name, or new term or concept
- </para>
- </entry>
- <entry colname="2">
- <filename>Fixed width</filename>
- </para>
- </entry>
- </row>
- <row>
- <entry colname="1">
- literal user
- input
- </para>
- </entry>
- <entry colname="2">
- <userinput>Fixed Width Bold</userinput>
- </para>
- </entry>
- </row>
- <row>
- <entry colname="1">
- program output
- </para>
- </entry>
- <entry colname="2">
- <computeroutput>Fixed Width</computeroutput>
- </para>
- </entry>
- </row>
- </tbody>
- </tgroup>
+ <tgroup cols="2">
+ <colspec colname="1" colnum="1" colwidth="3.000in"/>
+ <colspec colname="2" colnum="2" colwidth="2.625in"/>
+ <tbody>
+ <row>
+ <entry colname="1">
+ <para>
+ <emphasis>To describe:</emphasis>
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ <emphasis>We use the style:</emphasis>
+ </para>
+ </entry>
+ </row>
+ <row>
+ <entry colname="1">
+ <para>
+ a pathname, filename, URL, hostname,
+ mailing list name, or new term or concept
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ <filename>Fixed width</filename>
+ </para>
+ </entry>
+ </row>
+ <row>
+ <entry colname="1">
+ <para>
+ literal user
+ input
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ <userinput>Fixed Width Bold</userinput>
+ </para>
+ </entry>
+ </row>
+ <row>
+ <entry colname="1">
+ <para>
+ program output
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ <computeroutput>Fixed Width</computeroutput>
+ </para>
+ </entry>
+ </row>
+ </tbody>
+ </tgroup>
</informaltable>
<para>
- The following conventions are used in descriptions of the
-
<acronym>BIND</acronym> configuration file:<informaltable colsep="0" frame="all" rowsep="0">
- <tgroup cols="2" colsep="0" rowsep="0" tgroupstyle="2Level-table">
- <colspec colname="1" colnum="1" colsep="0" colwidth="3.000in"/>
- <colspec colname="2" colnum="2" colsep="0" colwidth="2.625in"/>
- <tbody>
- <row rowsep="0">
- <entry colname="1" colsep="1" rowsep="1">
- <emphasis>To describe:</emphasis>
- </para>
- </entry>
- <entry colname="2" rowsep="1">
- <emphasis>We use the style:</emphasis>
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1" colsep="1" rowsep="1">
- keywords
- </para>
- </entry>
- <entry colname="2" rowsep="1">
- <literal>Fixed Width</literal>
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1" colsep="1" rowsep="1">
- variables
- </para>
- </entry>
- <entry colname="2" rowsep="1">
- <varname>Fixed Width</varname>
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1" colsep="1">
- Optional input
- </para>
- </entry>
- <entry colname="2">
- <optional>Text is enclosed in square brackets</optional>
- </para>
- </entry>
- </row>
- </tbody>
- </tgroup>
- </informaltable>
+ The following conventions are used in descriptions of the
+ <acronym>BIND</acronym> configuration file:<informaltable colsep="0" frame="all" rowsep="0">
+ <tgroup cols="2" colsep="0" rowsep="0" tgroupstyle="2Level-table">
+ <colspec colname="1" colnum="1" colsep="0" colwidth="3.000in"/>
+ <colspec colname="2" colnum="2" colsep="0" colwidth="2.625in"/>
+ <tbody>
+ <row rowsep="0">
+ <entry colname="1" colsep="1" rowsep="1">
+ <para>
+ <emphasis>To describe:</emphasis>
+ </para>
+ </entry>
+ <entry colname="2" rowsep="1">
+ <para>
+ <emphasis>We use the style:</emphasis>
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1" colsep="1" rowsep="1">
+ <para>
+ keywords
+ </para>
+ </entry>
+ <entry colname="2" rowsep="1">
+ <para>
+ <literal>Fixed Width</literal>
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1" colsep="1" rowsep="1">
+ <para>
+ variables
+ </para>
+ </entry>
+ <entry colname="2" rowsep="1">
+ <para>
+ <varname>Fixed Width</varname>
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1" colsep="1">
+ <para>
+ Optional input
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ <optional>Text is enclosed in square brackets</optional>
+ </para>
+ </entry>
+ </row>
+ </tbody>
+ </tgroup>
+ </informaltable>
</para>
</sect1>
<sect1>
<title>The Domain Name System (<acronym>DNS</acronym>)</title>
<para>
- The purpose of this document is to explain the installation
-
and upkeep of the <acronym>BIND</acronym> (Berkeley Internet
+ The purpose of this document is to explain the installation
+ and upkeep of the <acronym>BIND</acronym> (Berkeley Internet
Name Domain) software package, and we
- begin by reviewing the fundamentals of the Domain Name System
-
(<acronym>DNS</acronym>) as they relate to <acronym>BIND</acronym>.
+ begin by reviewing the fundamentals of the Domain Name System
+ (<acronym>DNS</acronym>) as they relate to <acronym>BIND</acronym>.
</para>
<sect2>
- <title>DNS Fundamentals</title>
-
- The Domain Name System (DNS) is a hierarchical, distributed
- database. It stores information for mapping Internet host names to
- IP
- addresses and vice versa, mail routing information, and other data
- used by Internet applications.
- </para>
-
- Clients look up information in the DNS by calling a
- <emphasis>resolver</emphasis> library, which sends queries to one or
- more <emphasis>name servers</emphasis> and interprets the responses.
-
The <acronym>BIND</acronym> 9 software distribution
- contains a
- name server, <command>named</command>, and a resolver
- library, <command>liblwres</command>. The older
- <command>libbind</command> resolver library is also available
- from ISC as a separate download.
- </para>
-
- </sect2><sect2>
- <title>Domains and Domain Names</title>
-
- The data stored in the DNS is identified by <emphasis>domain names</emphasis> that are organized as a tree according to
- organizational or administrative boundaries. Each node of the tree,
- called a <emphasis>domain</emphasis>, is given a label. The domain
- name of the
- node is the concatenation of all the labels on the path from the
- node to the <emphasis>root</emphasis> node. This is represented
- in written form as a string of labels listed from right to left and
- separated by dots. A label need only be unique within its parent
- domain.
- </para>
-
- For example, a domain name for a host at the
- company <emphasis>Example, Inc.</emphasis> could be
- <literal>ourhost.example.com</literal>,
- where <literal>com</literal> is the
- top level domain to which
- <literal>ourhost.example.com</literal> belongs,
- <literal>example</literal> is
- a subdomain of <literal>com</literal>, and
- <literal>ourhost</literal> is the
- name of the host.
- </para>
-
- For administrative purposes, the name space is partitioned into
- areas called <emphasis>zones</emphasis>, each starting at a node and
- extending down to the leaf nodes or to nodes where other zones
- start.
- The data for each zone is stored in a <emphasis>name server</emphasis>, which answers queries about the zone using the
- <emphasis>DNS protocol</emphasis>.
- </para>
-
- The data associated with each domain name is stored in the
-
form of <emphasis>resource records</emphasis> (<acronym>RR</acronym>s).
- Some of the supported resource record types are described in
- <xref linkend="types_of_resource_records_and_when_to_use_them"/>.
- </para>
-
- For more detailed information about the design of the DNS and
- the DNS protocol, please refer to the standards documents listed in
- <xref linkend="rfcs"/>.
- </para>
+ <title>DNS Fundamentals</title>
+
+ <para>
+ The Domain Name System (DNS) is a hierarchical, distributed
+ database. It stores information for mapping Internet host names to
+ IP
+ addresses and vice versa, mail routing information, and other data
+ used by Internet applications.
+ </para>
+
+ <para>
+ Clients look up information in the DNS by calling a
+ <emphasis>resolver</emphasis> library, which sends queries to one or
+ more <emphasis>name servers</emphasis> and interprets the responses.
+ The <acronym>BIND</acronym> 9 software distribution
+ contains a
+ name server, <command>named</command>, and a resolver
+ library, <command>liblwres</command>. The older
+ <command>libbind</command> resolver library is also available
+ from ISC as a separate download.
+ </para>
+
+ </sect2><sect2>
+ <title>Domains and Domain Names</title>
+
+ <para>
+ The data stored in the DNS is identified by <emphasis>domain names</emphasis> that are organized as a tree according to
+ organizational or administrative boundaries. Each node of the tree,
+ called a <emphasis>domain</emphasis>, is given a label. The domain
+ name of the
+ node is the concatenation of all the labels on the path from the
+ node to the <emphasis>root</emphasis> node. This is represented
+ in written form as a string of labels listed from right to left and
+ separated by dots. A label need only be unique within its parent
+ domain.
+ </para>
+
+ <para>
+ For example, a domain name for a host at the
+ company <emphasis>Example, Inc.</emphasis> could be
+ <literal>ourhost.example.com</literal>,
+ where <literal>com</literal> is the
+ top level domain to which
+ <literal>ourhost.example.com</literal> belongs,
+ <literal>example</literal> is
+ a subdomain of <literal>com</literal>, and
+ <literal>ourhost</literal> is the
+ name of the host.
+ </para>
+
+ <para>
+ For administrative purposes, the name space is partitioned into
+ areas called <emphasis>zones</emphasis>, each starting at a node and
+ extending down to the leaf nodes or to nodes where other zones
+ start.
+ The data for each zone is stored in a <emphasis>name server</emphasis>, which answers queries about the zone using the
+ <emphasis>DNS protocol</emphasis>.
+ </para>
+
+ <para>
+ The data associated with each domain name is stored in the
+ form of <emphasis>resource records</emphasis> (<acronym>RR</acronym>s).
+ Some of the supported resource record types are described in
+ <xref linkend="types_of_resource_records_and_when_to_use_them"/>.
+ </para>
+
+ <para>
+ For more detailed information about the design of the DNS and
+ the DNS protocol, please refer to the standards documents listed in
+ <xref linkend="rfcs"/>.
+ </para>
</sect2>
<sect2>
- <title>Zones</title>
- To properly operate a name server, it is important to understand
- the difference between a <emphasis>zone</emphasis>
- and a <emphasis>domain</emphasis>.
- </para>
-
- As stated previously, a zone is a point of delegation in
-
the <acronym>DNS</acronym> tree. A zone consists of
- those contiguous parts of the domain
- tree for which a name server has complete information and over which
- it has authority. It contains all domain names from a certain point
- downward in the domain tree except those which are delegated to
- other zones. A delegation point is marked by one or more
- <emphasis>NS records</emphasis> in the
- parent zone, which should be matched by equivalent NS records at
- the root of the delegated zone.
- </para>
-
- For instance, consider the <literal>example.com</literal>
- domain which includes names
- such as <literal>host.aaa.example.com</literal> and
- <literal>host.bbb.example.com</literal> even though
- the <literal>example.com</literal> zone includes
- only delegations for the <literal>aaa.example.com</literal> and
- <literal>bbb.example.com</literal> zones. A zone can
- map
- exactly to a single domain, but could also include only part of a
- domain, the rest of which could be delegated to other
-
name servers. Every name in the <acronym>DNS</acronym>
- tree is a
- <emphasis>domain</emphasis>, even if it is
- <emphasis>terminal</emphasis>, that is, has no
- <emphasis>subdomains</emphasis>. Every subdomain is a domain and
- every domain except the root is also a subdomain. The terminology is
- not intuitive and we suggest that you read RFCs 1033, 1034 and 1035
- to
- gain a complete understanding of this difficult and subtle
- topic.
- </para>
-
-
Though <acronym>BIND</acronym> is called a "domain name
- server",
- it deals primarily in terms of zones. The master and slave
- declarations in the <filename>named.conf</filename> file
- specify
- zones, not domains. When you ask some other site if it is willing to
- be a slave server for your <emphasis>domain</emphasis>, you are
- actually asking for slave service for some collection of zones.
- </para>
+ <title>Zones</title>
+ <para>
+ To properly operate a name server, it is important to understand
+ the difference between a <emphasis>zone</emphasis>
+ and a <emphasis>domain</emphasis>.
+ </para>
+
+ <para>
+ As stated previously, a zone is a point of delegation in
+ the <acronym>DNS</acronym> tree. A zone consists of
+ those contiguous parts of the domain
+ tree for which a name server has complete information and over which
+ it has authority. It contains all domain names from a certain point
+ downward in the domain tree except those which are delegated to
+ other zones. A delegation point is marked by one or more
+ <emphasis>NS records</emphasis> in the
+ parent zone, which should be matched by equivalent NS records at
+ the root of the delegated zone.
+ </para>
+
+ <para>
+ For instance, consider the <literal>example.com</literal>
+ domain which includes names
+ such as <literal>host.aaa.example.com</literal> and
+ <literal>host.bbb.example.com</literal> even though
+ the <literal>example.com</literal> zone includes
+ only delegations for the <literal>aaa.example.com</literal> and
+ <literal>bbb.example.com</literal> zones. A zone can
+ map
+ exactly to a single domain, but could also include only part of a
+ domain, the rest of which could be delegated to other
+ name servers. Every name in the <acronym>DNS</acronym>
+ tree is a
+ <emphasis>domain</emphasis>, even if it is
+ <emphasis>terminal</emphasis>, that is, has no
+ <emphasis>subdomains</emphasis>. Every subdomain is a domain and
+ every domain except the root is also a subdomain. The terminology is
+ not intuitive and we suggest that you read RFCs 1033, 1034 and 1035
+ to
+ gain a complete understanding of this difficult and subtle
+ topic.
+ </para>
+
+ <para>
+ Though <acronym>BIND</acronym> is called a "domain name
+ server",
+ it deals primarily in terms of zones. The master and slave
+ declarations in the <filename>named.conf</filename> file
+ specify
+ zones, not domains. When you ask some other site if it is willing to
+ be a slave server for your <emphasis>domain</emphasis>, you are
+ actually asking for slave service for some collection of zones.
+ </para>
</sect2>
<sect2>
- <title>Authoritative Name Servers</title>
-
- Each zone is served by at least
- one <emphasis>authoritative name server</emphasis>,
- which contains the complete data for the zone.
- To make the DNS tolerant of server and network failures,
- most zones have two or more authoritative servers, on
- different networks.
- </para>
-
- Responses from authoritative servers have the "authoritative
- answer" (AA) bit set in the response packets. This makes them
- easy to identify when debugging DNS configurations using tools like
- <command>dig</command> (<xref linkend="diagnostic_tools"/>).
- </para>
-
- <sect3>
- <title>The Primary Master</title>
-
- The authoritative server where the master copy of the zone
- data is maintained is called the
+ <title>Authoritative Name Servers</title>
+
+ <para>
+ Each zone is served by at least
+ one <emphasis>authoritative name server</emphasis>,
+ which contains the complete data for the zone.
+ To make the DNS tolerant of server and network failures,
+ most zones have two or more authoritative servers, on
+ different networks.
+ </para>
+
+ <para>
+ Responses from authoritative servers have the "authoritative
+ answer" (AA) bit set in the response packets. This makes them
+ easy to identify when debugging DNS configurations using tools like
+ <command>dig</command> (<xref linkend="diagnostic_tools"/>).
+ </para>
+
+ <sect3>
+ <title>The Primary Master</title>
+
+ <para>
+ The authoritative server where the master copy of the zone
+ data is maintained is called the
<emphasis>primary master</emphasis> server, or simply the
- <emphasis>primary</emphasis>. Typically it loads the zone
- contents from some local file edited by humans or perhaps
- generated mechanically from some other local file which is
- edited by humans. This file is called the
+ <emphasis>primary</emphasis>. Typically it loads the zone
+ contents from some local file edited by humans or perhaps
+ generated mechanically from some other local file which is
+ edited by humans. This file is called the
<emphasis>zone file</emphasis> or
<emphasis>master file</emphasis>.
- </para>
+ </para>
<para>
In some cases, however, the master file may not be edited
by humans at all, but may instead be the result of
<emphasis>dynamic update</emphasis> operations.
</para>
- </sect3>
-
- <sect3>
- <title>Slave Servers</title>
- The other authoritative servers, the <emphasis>slave</emphasis>
- servers (also known as <emphasis>secondary</emphasis> servers)
- load
- the zone contents from another server using a replication process
- known as a <emphasis>zone transfer</emphasis>. Typically the data
- are
- transferred directly from the primary master, but it is also
- possible
- to transfer it from another slave. In other words, a slave server
- may itself act as a master to a subordinate slave server.
- </para>
- </sect3>
-
- <sect3>
- <title>Stealth Servers</title>
-
- Usually all of the zone's authoritative servers are listed in
- NS records in the parent zone. These NS records constitute
- a <emphasis>delegation</emphasis> of the zone from the parent.
- The authoritative servers are also listed in the zone file itself,
- at the <emphasis>top level</emphasis> or <emphasis>apex</emphasis>
- of the zone. You can list servers in the zone's top-level NS
- records that are not in the parent's NS delegation, but you cannot
- list servers in the parent's delegation that are not present at
- the zone's top level.
- </para>
-
- A <emphasis>stealth server</emphasis> is a server that is
- authoritative for a zone but is not listed in that zone's NS
- records. Stealth servers can be used for keeping a local copy of
- a
- zone to speed up access to the zone's records or to make sure that
- the
- zone is available even if all the "official" servers for the zone
- are
- inaccessible.
- </para>
-
- A configuration where the primary master server itself is a
- stealth server is often referred to as a "hidden primary"
- configuration. One use for this configuration is when the primary
- master
- is behind a firewall and therefore unable to communicate directly
- with the outside world.
- </para>
-
- </sect3>
+ </sect3>
+
+ <sect3>
+ <title>Slave Servers</title>
+ <para>
+ The other authoritative servers, the <emphasis>slave</emphasis>
+ servers (also known as <emphasis>secondary</emphasis> servers)
+ load
+ the zone contents from another server using a replication process
+ known as a <emphasis>zone transfer</emphasis>. Typically the data
+ are
+ transferred directly from the primary master, but it is also
+ possible
+ to transfer it from another slave. In other words, a slave server
+ may itself act as a master to a subordinate slave server.
+ </para>
+ </sect3>
+
+ <sect3>
+ <title>Stealth Servers</title>
+
+ <para>
+ Usually all of the zone's authoritative servers are listed in
+ NS records in the parent zone. These NS records constitute
+ a <emphasis>delegation</emphasis> of the zone from the parent.
+ The authoritative servers are also listed in the zone file itself,
+ at the <emphasis>top level</emphasis> or <emphasis>apex</emphasis>
+ of the zone. You can list servers in the zone's top-level NS
+ records that are not in the parent's NS delegation, but you cannot
+ list servers in the parent's delegation that are not present at
+ the zone's top level.
+ </para>
+
+ <para>
+ A <emphasis>stealth server</emphasis> is a server that is
+ authoritative for a zone but is not listed in that zone's NS
+ records. Stealth servers can be used for keeping a local copy of
+ a
+ zone to speed up access to the zone's records or to make sure that
+ the
+ zone is available even if all the "official" servers for the zone
+ are
+ inaccessible.
+ </para>
+
+ <para>
+ A configuration where the primary master server itself is a
+ stealth server is often referred to as a "hidden primary"
+ configuration. One use for this configuration is when the primary
+ master
+ is behind a firewall and therefore unable to communicate directly
+ with the outside world.
+ </para>
+
+ </sect3>
</sect2>
<sect2>
- <title>Caching Name Servers</title>
+ <title>Caching Name Servers</title>
<!--
- Terminology here is inconsistent. Probably ought to
- with just a note about "caching" terminology.
-->
- The resolver libraries provided by most operating systems are
- <emphasis>stub resolvers</emphasis>, meaning that they are not
- capable of
- performing the full DNS resolution process by themselves by talking
- directly to the authoritative servers. Instead, they rely on a
- local
- name server to perform the resolution on their behalf. Such a
- server
- is called a <emphasis>recursive</emphasis> name server; it performs
- <emphasis>recursive lookups</emphasis> for local clients.
- </para>
-
- To improve performance, recursive servers cache the results of
- the lookups they perform. Since the processes of recursion and
- caching are intimately connected, the terms
- <emphasis>recursive server</emphasis> and
- <emphasis>caching server</emphasis> are often used synonymously.
- </para>
-
- The length of time for which a record may be retained in
- the cache of a caching name server is controlled by the
- Time To Live (TTL) field associated with each resource record.
- </para>
-
- <sect3>
- <title>Forwarding</title>
-
- Even a caching name server does not necessarily perform
- the complete recursive lookup itself. Instead, it can
- <emphasis>forward</emphasis> some or all of the queries
- that it cannot satisfy from its cache to another caching name
- server,
- commonly referred to as a <emphasis>forwarder</emphasis>.
- </para>
-
- There may be one or more forwarders,
- and they are queried in turn until the list is exhausted or an
- answer
- is found. Forwarders are typically used when you do not
- wish all the servers at a given site to interact directly with the
- rest of
- the Internet servers. A typical scenario would involve a number
-
of internal <acronym>DNS</acronym> servers and an
- Internet firewall. Servers unable
- to pass packets through the firewall would forward to the server
-
that can do it, and that server would query the Internet <acronym>DNS</acronym> servers
- on the internal server's behalf.
- </para>
- </sect3>
+ <para>
+ The resolver libraries provided by most operating systems are
+ <emphasis>stub resolvers</emphasis>, meaning that they are not
+ capable of
+ performing the full DNS resolution process by themselves by talking
+ directly to the authoritative servers. Instead, they rely on a
+ local
+ name server to perform the resolution on their behalf. Such a
+ server
+ is called a <emphasis>recursive</emphasis> name server; it performs
+ <emphasis>recursive lookups</emphasis> for local clients.
+ </para>
+
+ <para>
+ To improve performance, recursive servers cache the results of
+ the lookups they perform. Since the processes of recursion and
+ caching are intimately connected, the terms
+ <emphasis>recursive server</emphasis> and
+ <emphasis>caching server</emphasis> are often used synonymously.
+ </para>
+
+ <para>
+ The length of time for which a record may be retained in
+ the cache of a caching name server is controlled by the
+ Time To Live (TTL) field associated with each resource record.
+ </para>
+
+ <sect3>
+ <title>Forwarding</title>
+
+ <para>
+ Even a caching name server does not necessarily perform
+ the complete recursive lookup itself. Instead, it can
+ <emphasis>forward</emphasis> some or all of the queries
+ that it cannot satisfy from its cache to another caching name
+ server,
+ commonly referred to as a <emphasis>forwarder</emphasis>.
+ </para>
+
+ <para>
+ There may be one or more forwarders,
+ and they are queried in turn until the list is exhausted or an
+ answer
+ is found. Forwarders are typically used when you do not
+ wish all the servers at a given site to interact directly with the
+ rest of
+ the Internet servers. A typical scenario would involve a number
+ of internal <acronym>DNS</acronym> servers and an
+ Internet firewall. Servers unable
+ to pass packets through the firewall would forward to the server
+ that can do it, and that server would query the Internet <acronym>DNS</acronym> servers
+ on the internal server's behalf.
+ </para>
+ </sect3>
</sect2>
<sect2>
- <title>Name Servers in Multiple Roles</title>
-
-
The <acronym>BIND</acronym> name server can
- simultaneously act as
- a master for some zones, a slave for other zones, and as a caching
- (recursive) server for a set of local clients.
- </para>
-
- However, since the functions of authoritative name service
- and caching/recursive name service are logically separate, it is
- often advantageous to run them on separate server machines.
-
- A server that only provides authoritative name service
- (an <emphasis>authoritative-only</emphasis> server) can run with
- recursion disabled, improving reliability and security.
-
- A server that is not authoritative for any zones and only provides
- recursive service to local
- clients (a <emphasis>caching-only</emphasis> server)
- does not need to be reachable from the Internet at large and can
- be placed inside a firewall.
- </para>
+ <title>Name Servers in Multiple Roles</title>
+
+ <para>
+ The <acronym>BIND</acronym> name server can
+ simultaneously act as
+ a master for some zones, a slave for other zones, and as a caching
+ (recursive) server for a set of local clients.
+ </para>
+
+ <para>
+ However, since the functions of authoritative name service
+ and caching/recursive name service are logically separate, it is
+ often advantageous to run them on separate server machines.
+
+ A server that only provides authoritative name service
+ (an <emphasis>authoritative-only</emphasis> server) can run with
+ recursion disabled, improving reliability and security.
+
+ A server that is not authoritative for any zones and only provides
+ recursive service to local
+ clients (a <emphasis>caching-only</emphasis> server)
+ does not need to be reachable from the Internet at large and can
+ be placed inside a firewall.
+ </para>
</sect2>
</sect1>
<title>Hardware requirements</title>
<para>
-
<acronym>DNS</acronym> hardware requirements have
- traditionally been quite modest.
- For many installations, servers that have been pensioned off from
-
active duty have performed admirably as <acronym>DNS</acronym> servers.
+ <acronym>DNS</acronym> hardware requirements have
+ traditionally been quite modest.
+ For many installations, servers that have been pensioned off from
+ active duty have performed admirably as <acronym>DNS</acronym> servers.
</para>
<para>
-
The DNSSEC features of <acronym>BIND</acronym> 9
- may prove to be quite
- CPU intensive however, so organizations that make heavy use of these
- features may wish to consider larger systems for these applications.
-
<acronym>BIND</acronym> 9 is fully multithreaded, allowing
- full utilization of
- multiprocessor systems for installations that need it.
+ The DNSSEC features of <acronym>BIND</acronym> 9
+ may prove to be quite
+ CPU intensive however, so organizations that make heavy use of these
+ features may wish to consider larger systems for these applications.
+ <acronym>BIND</acronym> 9 is fully multithreaded, allowing
+ full utilization of
+ multiprocessor systems for installations that need it.
</para>
</sect1>
<sect1>
<title>CPU Requirements</title>
<para>
-
CPU requirements for <acronym>BIND</acronym> 9 range from
- i486-class machines
- for serving of static zones without caching, to enterprise-class
- machines if you intend to process many dynamic updates and DNSSEC
- signed zones, serving many thousands of queries per second.
+ CPU requirements for <acronym>BIND</acronym> 9 range from
+ i486-class machines
+ for serving of static zones without caching, to enterprise-class
+ machines if you intend to process many dynamic updates and DNSSEC
+ signed zones, serving many thousands of queries per second.
</para>
</sect1>
<sect1>
<title>Memory Requirements</title>
<para>
- The memory of the server has to be large enough to fit the
- cache and zones loaded off disk. The <command>max-cache-size</command>
- option can be used to limit the amount of memory used by the cache,
-
at the expense of reducing cache hit rates and causing more <acronym>DNS</acronym>
- traffic.
- Additionally, if additional section caching
- (<xref linkend="acache"/>) is enabled,
- the <command>max-acache-size</command> option can be used to
- limit the amount
- of memory used by the mechanism.
- It is still good practice to have enough memory to load
- all zone and cache data into memory — unfortunately, the best
- way
- to determine this for a given installation is to watch the name server
- in operation. After a few weeks the server process should reach
- a relatively stable size where entries are expiring from the cache as
- fast as they are being inserted.
+ The memory of the server has to be large enough to fit the
+ cache and zones loaded off disk. The <command>max-cache-size</command>
+ option can be used to limit the amount of memory used by the cache,
+ at the expense of reducing cache hit rates and causing more <acronym>DNS</acronym>
+ traffic.
+ Additionally, if additional section caching
+ (<xref linkend="acache"/>) is enabled,
+ the <command>max-acache-size</command> option can be used to
+ limit the amount
+ of memory used by the mechanism.
+ It is still good practice to have enough memory to load
+ all zone and cache data into memory — unfortunately, the best
+ way
+ to determine this for a given installation is to watch the name server
+ in operation. After a few weeks the server process should reach
+ a relatively stable size where entries are expiring from the cache as
+ fast as they are being inserted.
</para>
<!--
- - Add something here about leaving overhead for attacks?
+ - Add something here about leaving overhead for attacks?
- How much overhead? Percentage?
- -->
+ -->
</sect1>
<sect1>
<title>Name Server Intensive Environment Issues</title>
<para>
- For name server intensive environments, there are two alternative
- configurations that may be used. The first is where clients and
- any second-level internal name servers query a main name server, which
- has enough memory to build a large cache. This approach minimizes
- the bandwidth used by external name lookups. The second alternative
- is to set up second-level internal name servers to make queries
- independently.
- In this configuration, none of the individual machines needs to
- have as much memory or CPU power as in the first alternative, but
- this has the disadvantage of making many more external queries,
- as none of the name servers share their cached data.
+ For name server intensive environments, there are two alternative
+ configurations that may be used. The first is where clients and
+ any second-level internal name servers query a main name server, which
+ has enough memory to build a large cache. This approach minimizes
+ the bandwidth used by external name lookups. The second alternative
+ is to set up second-level internal name servers to make queries
+ independently.
+ In this configuration, none of the individual machines needs to
+ have as much memory or CPU power as in the first alternative, but
+ this has the disadvantage of making many more external queries,
+ as none of the name servers share their cached data.
</para>
</sect1>
<sect1>
<title>Supported Operating Systems</title>
<para>
-
ISC <acronym>BIND</acronym> 9 compiles and runs on a large
- number
- of Unix-like operating systems and on
- Microsoft Windows Server 2003 and 2008, and Windows XP and Vista.
- For an up-to-date
- list of supported systems, see the README file in the top level
- directory
- of the BIND 9 source distribution.
+ ISC <acronym>BIND</acronym> 9 compiles and runs on a large
+ number
+ of Unix-like operating systems and on
+ Microsoft Windows Server 2003 and 2008, and Windows XP and Vista.
+ For an up-to-date
+ list of supported systems, see the README file in the top level
+ directory
+ of the BIND 9 source distribution.
</para>
</sect1>
</chapter>
<sect1 id="sample_configuration">
<title>Sample Configurations</title>
<sect2>
- <title>A Caching-only Name Server</title>
- The following sample configuration is appropriate for a caching-only
- name server for use by clients internal to a corporation. All
- queries
- from outside clients are refused using the <command>allow-query</command>
- option. Alternatively, the same effect could be achieved using
- suitable
- firewall rules.
- </para>
+ <title>A Caching-only Name Server</title>
+ <para>
+ The following sample configuration is appropriate for a caching-only
+ name server for use by clients internal to a corporation. All
+ queries
+ from outside clients are refused using the <command>allow-query</command>
+ option. Alternatively, the same effect could be achieved using
+ suitable
+ firewall rules.
+ </para>
<programlisting>
// Two corporate subnets we wish to allow queries from.
</sect2>
<sect2>
- <title>An Authoritative-only Name Server</title>
- This sample configuration is for an authoritative-only server
- that is the master server for "<filename>example.com</filename>"
- and a slave for the subdomain "<filename>eng.example.com</filename>".
- </para>
+ <title>An Authoritative-only Name Server</title>
+ <para>
+ This sample configuration is for an authoritative-only server
+ that is the master server for "<filename>example.com</filename>"
+ and a slave for the subdomain "<filename>eng.example.com</filename>".
+ </para>
<programlisting>
options {
// IP addresses of slave servers allowed to
// transfer example.com
allow-transfer {
- 192.168.4.14;
- 192.168.5.53;
+ 192.168.4.14;
+ 192.168.5.53;
};
};
// We are a slave server for eng.example.com
<sect1>
<title>Load Balancing</title>
<!--
- - Add explanation of why load balancing is fragile at best
+ - Add explanation of why load balancing is fragile at best
- and completely pointless in the general case.
- -->
+ -->
<para>
- A primitive form of load balancing can be achieved in
-
the <acronym>DNS</acronym> by using multiple records
+ A primitive form of load balancing can be achieved in
+ the <acronym>DNS</acronym> by using multiple records
(such as multiple A records) for one name.
</para>
<para>
- For example, if you have three WWW servers with network addresses
- of 10.0.0.1, 10.0.0.2 and 10.0.0.3, a set of records such as the
- following means that clients will connect to each machine one third
- of the time:
+ For example, if you have three WWW servers with network addresses
+ of 10.0.0.1, 10.0.0.2 and 10.0.0.3, a set of records such as the
+ following means that clients will connect to each machine one third
+ of the time:
</para>
<informaltable colsep="0" rowsep="0">
- <tgroup cols="5" colsep="0" rowsep="0" tgroupstyle="2Level-table">
- <colspec colname="1" colnum="1" colsep="0" colwidth="0.875in"/>
- <colspec colname="2" colnum="2" colsep="0" colwidth="0.500in"/>
- <colspec colname="3" colnum="3" colsep="0" colwidth="0.750in"/>
- <colspec colname="4" colnum="4" colsep="0" colwidth="0.750in"/>
- <colspec colname="5" colnum="5" colsep="0" colwidth="2.028in"/>
- <tbody>
- <row rowsep="0">
- <entry colname="1">
- Name
- </para>
- </entry>
- <entry colname="2">
- TTL
- </para>
- </entry>
- <entry colname="3">
- CLASS
- </para>
- </entry>
- <entry colname="4">
- TYPE
- </para>
- </entry>
- <entry colname="5">
- Resource Record (RR) Data
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <literal>www</literal>
- </para>
- </entry>
- <entry colname="2">
- <literal>600</literal>
- </para>
- </entry>
- <entry colname="3">
- <literal>IN</literal>
- </para>
- </entry>
- <entry colname="4">
- <literal>A</literal>
- </para>
- </entry>
- <entry colname="5">
- <literal>10.0.0.1</literal>
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- </entry>
- <entry colname="2">
- <literal>600</literal>
- </para>
- </entry>
- <entry colname="3">
- <literal>IN</literal>
- </para>
- </entry>
- <entry colname="4">
- <literal>A</literal>
- </para>
- </entry>
- <entry colname="5">
- <literal>10.0.0.2</literal>
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- </entry>
- <entry colname="2">
- <literal>600</literal>
- </para>
- </entry>
- <entry colname="3">
- <literal>IN</literal>
- </para>
- </entry>
- <entry colname="4">
- <literal>A</literal>
- </para>
- </entry>
- <entry colname="5">
- <literal>10.0.0.3</literal>
- </para>
- </entry>
- </row>
- </tbody>
- </tgroup>
+ <tgroup cols="5" colsep="0" rowsep="0" tgroupstyle="2Level-table">
+ <colspec colname="1" colnum="1" colsep="0" colwidth="0.875in"/>
+ <colspec colname="2" colnum="2" colsep="0" colwidth="0.500in"/>
+ <colspec colname="3" colnum="3" colsep="0" colwidth="0.750in"/>
+ <colspec colname="4" colnum="4" colsep="0" colwidth="0.750in"/>
+ <colspec colname="5" colnum="5" colsep="0" colwidth="2.028in"/>
+ <tbody>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ Name
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ TTL
+ </para>
+ </entry>
+ <entry colname="3">
+ <para>
+ CLASS
+ </para>
+ </entry>
+ <entry colname="4">
+ <para>
+ TYPE
+ </para>
+ </entry>
+ <entry colname="5">
+ <para>
+ Resource Record (RR) Data
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ <literal>www</literal>
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ <literal>600</literal>
+ </para>
+ </entry>
+ <entry colname="3">
+ <para>
+ <literal>IN</literal>
+ </para>
+ </entry>
+ <entry colname="4">
+ <para>
+ <literal>A</literal>
+ </para>
+ </entry>
+ <entry colname="5">
+ <para>
+ <literal>10.0.0.1</literal>
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para/>
+ </entry>
+ <entry colname="2">
+ <para>
+ <literal>600</literal>
+ </para>
+ </entry>
+ <entry colname="3">
+ <para>
+ <literal>IN</literal>
+ </para>
+ </entry>
+ <entry colname="4">
+ <para>
+ <literal>A</literal>
+ </para>
+ </entry>
+ <entry colname="5">
+ <para>
+ <literal>10.0.0.2</literal>
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para/>
+ </entry>
+ <entry colname="2">
+ <para>
+ <literal>600</literal>
+ </para>
+ </entry>
+ <entry colname="3">
+ <para>
+ <literal>IN</literal>
+ </para>
+ </entry>
+ <entry colname="4">
+ <para>
+ <literal>A</literal>
+ </para>
+ </entry>
+ <entry colname="5">
+ <para>
+ <literal>10.0.0.3</literal>
+ </para>
+ </entry>
+ </row>
+ </tbody>
+ </tgroup>
</informaltable>
<para>
-
When a resolver queries for these records, <acronym>BIND</acronym> will rotate
- them and respond to the query with the records in a different
- order. In the example above, clients will randomly receive
- records in the order 1, 2, 3; 2, 3, 1; and 3, 1, 2. Most clients
- will use the first record returned and discard the rest.
+ When a resolver queries for these records, <acronym>BIND</acronym> will rotate
+ them and respond to the query with the records in a different
+ order. In the example above, clients will randomly receive
+ records in the order 1, 2, 3; 2, 3, 1; and 3, 1, 2. Most clients
+ will use the first record returned and discard the rest.
</para>
<para>
- For more detail on ordering responses, check the
- <command>rrset-order</command> sub-statement in the
- <command>options</command> statement, see
- <xref endterm="rrset_ordering_title" linkend="rrset_ordering"/>.
+ For more detail on ordering responses, check the
+ <command>rrset-order</command> sub-statement in the
+ <command>options</command> statement, see
+ <xref endterm="rrset_ordering_title" linkend="rrset_ordering"/>.
</para>
</sect1>
<title>Name Server Operations</title>
<sect2>
- <title>Tools for Use With the Name Server Daemon</title>
- This section describes several indispensable diagnostic,
- administrative and monitoring tools available to the system
- administrator for controlling and debugging the name server
- daemon.
- </para>
- <sect3 id="diagnostic_tools">
- <title>Diagnostic Tools</title>
- The <command>dig</command>, <command>host</command>, and
- <command>nslookup</command> programs are all command
- line tools
- for manually querying name servers. They differ in style and
- output format.
- </para>
-
- <variablelist>
- <varlistentry>
- <term id="dig"><command>dig</command></term>
- <listitem>
- The domain information groper (<command>dig</command>)
- is the most versatile and complete of these lookup tools.
- It has two modes: simple interactive
- mode for a single query, and batch mode which executes a
- query for
- each in a list of several query lines. All query options are
- accessible
- from the command line.
- </para>
- <cmdsynopsis label="Usage">
- <command>dig</command>
-
<arg>@<replaceable>server</replaceable></arg>
-
<arg choice="plain"><replaceable>domain</replaceable></arg>
-
<arg><replaceable>query-type</replaceable></arg>
-
<arg><replaceable>query-class</replaceable></arg>
-
<arg>+<replaceable>query-option</replaceable></arg>
-
<arg>-<replaceable>dig-option</replaceable></arg>
-
<arg>%<replaceable>comment</replaceable></arg>
- </cmdsynopsis>
- The usual simple use of <command>dig</command> will take the form
- </para>
- <simpara>
- <command>dig @server domain query-type query-class</command>
- </simpara>
- For more information and a list of available commands and
- options, see the <command>dig</command> man
- page.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>host</command></term>
- <listitem>
- The <command>host</command> utility emphasizes
- simplicity
- and ease of use. By default, it converts
- between host names and Internet addresses, but its
- functionality
- can be extended with the use of options.
- </para>
- <cmdsynopsis label="Usage">
- <command>host</command>
-
<arg>-c <replaceable>class</replaceable></arg>
-
<arg>-N <replaceable>ndots</replaceable></arg>
-
<arg>-t <replaceable>type</replaceable></arg>
-
<arg>-W <replaceable>timeout</replaceable></arg>
-
<arg>-R <replaceable>retries</replaceable></arg>
-
<arg>-m <replaceable>flag</replaceable></arg>
+ <title>Tools for Use With the Name Server Daemon</title>
+ <para>
+ This section describes several indispensable diagnostic,
+ administrative and monitoring tools available to the system
+ administrator for controlling and debugging the name server
+ daemon.
+ </para>
+ <sect3 id="diagnostic_tools">
+ <title>Diagnostic Tools</title>
+ <para>
+ The <command>dig</command>, <command>host</command>, and
+ <command>nslookup</command> programs are all command
+ line tools
+ for manually querying name servers. They differ in style and
+ output format.
+ </para>
+
+ <variablelist>
+ <varlistentry>
+ <term id="dig"><command>dig</command></term>
+ <listitem>
+ <para>
+ The domain information groper (<command>dig</command>)
+ is the most versatile and complete of these lookup tools.
+ It has two modes: simple interactive
+ mode for a single query, and batch mode which executes a
+ query for
+ each in a list of several query lines. All query options are
+ accessible
+ from the command line.
+ </para>
+ <cmdsynopsis label="Usage">
+ <command>dig</command>
+ <arg>@<replaceable>server</replaceable></arg>
+ <arg choice="plain"><replaceable>domain</replaceable></arg>
+ <arg><replaceable>query-type</replaceable></arg>
+ <arg><replaceable>query-class</replaceable></arg>
+ <arg>+<replaceable>query-option</replaceable></arg>
+ <arg>-<replaceable>dig-option</replaceable></arg>
+ <arg>%<replaceable>comment</replaceable></arg>
+ </cmdsynopsis>
+ <para>
+ The usual simple use of <command>dig</command> will take the form
+ </para>
+ <simpara>
+ <command>dig @server domain query-type query-class</command>
+ </simpara>
+ <para>
+ For more information and a list of available commands and
+ options, see the <command>dig</command> man
+ page.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>host</command></term>
+ <listitem>
+ <para>
+ The <command>host</command> utility emphasizes
+ simplicity
+ and ease of use. By default, it converts
+ between host names and Internet addresses, but its
+ functionality
+ can be extended with the use of options.
+ </para>
+ <cmdsynopsis label="Usage">
+ <command>host</command>
+ <arg>-aCdlnrsTwv</arg>
+ <arg>-c <replaceable>class</replaceable></arg>
+ <arg>-N <replaceable>ndots</replaceable></arg>
+ <arg>-t <replaceable>type</replaceable></arg>
+ <arg>-W <replaceable>timeout</replaceable></arg>
+ <arg>-R <replaceable>retries</replaceable></arg>
+ <arg>-m <replaceable>flag</replaceable></arg>
<arg>-4</arg>
<arg>-6</arg>
- <arg choice="plain"><replaceable>hostname</replaceable></arg>
- <arg><replaceable>server</replaceable></arg>
- </cmdsynopsis>
- <para>
- For more information and a list of available commands and
- options, see the <command>host</command> man
- page.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>nslookup</command></term>
- <listitem>
- <para><command>nslookup</command>
- has two modes: interactive and
- non-interactive. Interactive mode allows the user to
- query name servers for information about various
- hosts and domains or to print a list of hosts in a
- domain. Non-interactive mode is used to print just
- the name and requested information for a host or
- domain.
- </para>
- <cmdsynopsis label="Usage">
- <command>nslookup</command>
- <arg rep="repeat">-option</arg>
- <group>
- <arg><replaceable>host-to-find</replaceable></arg>
- <arg>- <arg>server</arg></arg>
- </group>
- </cmdsynopsis>
- <para>
- Interactive mode is entered when no arguments are given (the
- default name server will be used) or when the first argument
- is a
- hyphen (`-') and the second argument is the host name or
- Internet address
- of a name server.
- </para>
- <para>
- Non-interactive mode is used when the name or Internet
- address
- of the host to be looked up is given as the first argument.
- The
- optional second argument specifies the host name or address
- of a name server.
- </para>
- <para>
- Due to its arcane user interface and frequently inconsistent
- behavior, we do not recommend the use of <command>nslookup</command>.
- Use <command>dig</command> instead.
- </para>
- </listitem>
-
- </varlistentry>
- </variablelist>
- </sect3>
-
- <sect3 id="admin_tools">
- <title>Administrative Tools</title>
- <para>
- Administrative tools play an integral part in the management
- of a server.
- </para>
- <variablelist>
- <varlistentry id="named-checkconf" xreflabel="Named Configuration Checking application">
-
- <term><command>named-checkconf</command></term>
- <listitem>
- <para>
- The <command>named-checkconf</command> program
- checks the syntax of a <filename>named.conf</filename> file.
- </para>
- <cmdsynopsis label="Usage">
- <command>named-checkconf</command>
- <arg>-jvz</arg>
- <arg>-t <replaceable>directory</replaceable></arg>
- <arg><replaceable>filename</replaceable></arg>
- </cmdsynopsis>
- </listitem>
- </varlistentry>
- <varlistentry id="named-checkzone" xreflabel="Zone Checking application">
-
- <term><command>named-checkzone</command></term>
- <listitem>
- <para>
- The <command>named-checkzone</command> program
- checks a master file for
- syntax and consistency.
- </para>
- <cmdsynopsis label="Usage">
- <command>named-checkzone</command>
- <arg>-djqvD</arg>
- <arg>-c <replaceable>class</replaceable></arg>
- <arg>-o <replaceable>output</replaceable></arg>
- <arg>-t <replaceable>directory</replaceable></arg>
- <arg>-w <replaceable>directory</replaceable></arg>
- <arg>-k <replaceable>(ignore|warn|fail)</replaceable></arg>
- <arg>-n <replaceable>(ignore|warn|fail)</replaceable></arg>
- <arg>-W <replaceable>(ignore|warn)</replaceable></arg>
- <arg choice="plain"><replaceable>zone</replaceable></arg>
- <arg><replaceable>filename</replaceable></arg>
- </cmdsynopsis>
- </listitem>
- </varlistentry>
- <varlistentry id="named-compilezone" xreflabel="Zone Compilation application">
- <term><command>named-compilezone</command></term>
+ <arg choice="plain"><replaceable>hostname</replaceable></arg>
+ <arg><replaceable>server</replaceable></arg>
+ </cmdsynopsis>
+ <para>
+ For more information and a list of available commands and
+ options, see the <command>host</command> man
+ page.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>nslookup</command></term>
<listitem>
+ <para><command>nslookup</command>
+ has two modes: interactive and
+ non-interactive. Interactive mode allows the user to
+ query name servers for information about various
+ hosts and domains or to print a list of hosts in a
+ domain. Non-interactive mode is used to print just
+ the name and requested information for a host or
+ domain.
+ </para>
+ <cmdsynopsis label="Usage">
+ <command>nslookup</command>
+ <arg rep="repeat">-option</arg>
+ <group>
+ <arg><replaceable>host-to-find</replaceable></arg>
+ <arg>- <arg>server</arg></arg>
+ </group>
+ </cmdsynopsis>
<para>
- Similar to <command>named-checkzone,</command> but
- it always dumps the zone content to a specified file
- (typically in a different format).
+ Interactive mode is entered when no arguments are given (the
+ default name server will be used) or when the first argument
+ is a
+ hyphen (`-') and the second argument is the host name or
+ Internet address
+ of a name server.
+ </para>
+ <para>
+ Non-interactive mode is used when the name or Internet
+ address
+ of the host to be looked up is given as the first argument.
+ The
+ optional second argument specifies the host name or address
+ of a name server.
+ </para>
+ <para>
+ Due to its arcane user interface and frequently inconsistent
+ behavior, we do not recommend the use of <command>nslookup</command>.
+ Use <command>dig</command> instead.
</para>
</listitem>
+
</varlistentry>
- <varlistentry id="rndc" xreflabel="Remote Name Daemon Control application">
-
- <term><command>rndc</command></term>
- <listitem>
- <para>
- The remote name daemon control
- (<command>rndc</command>) program allows the
- system
- administrator to control the operation of a name server.
- Since <acronym>BIND</acronym> 9.2, <command>rndc</command>
- supports all the commands of the BIND 8 <command>ndc</command>
- utility except <command>ndc start</command> and
- <command>ndc restart</command>, which were also
- not supported in <command>ndc</command>'s
- channel mode.
- If you run <command>rndc</command> without any
- options
- it will display a usage message as follows:
- </para>
- <cmdsynopsis label="Usage">
- <command>rndc</command>
- <arg>-c <replaceable>config</replaceable></arg>
- <arg>-s <replaceable>server</replaceable></arg>
- <arg>-p <replaceable>port</replaceable></arg>
- <arg>-y <replaceable>key</replaceable></arg>
- <arg choice="plain"><replaceable>command</replaceable></arg>
- <arg rep="repeat"><replaceable>command</replaceable></arg>
- </cmdsynopsis>
-
- <para>See <xref linkend="man.rndc"/> for details of
- the available <command>rndc</command> commands.
- </para>
-
- <para>
- <command>rndc</command> requires a configuration file,
- since all
- communication with the server is authenticated with
- digital signatures that rely on a shared secret, and
- there is no way to provide that secret other than with a
- configuration file. The default location for the
- <command>rndc</command> configuration file is
- <filename>/etc/rndc.conf</filename>, but an
- alternate
- location can be specified with the <option>-c</option>
- option. If the configuration file is not found,
- <command>rndc</command> will also look in
- <filename>/etc/rndc.key</filename> (or whatever
- <varname>sysconfdir</varname> was defined when
- the <acronym>BIND</acronym> build was
- configured).
- The <filename>rndc.key</filename> file is
- generated by
- running <command>rndc-confgen -a</command> as
- described in
- <xref linkend="controls_statement_definition_and_usage"/>.
- </para>
-
- <para>
- The format of the configuration file is similar to
- that of <filename>named.conf</filename>, but
- limited to
- only four statements, the <command>options</command>,
- <command>key</command>, <command>server</command> and
- <command>include</command>
- statements. These statements are what associate the
- secret keys to the servers with which they are meant to
- be shared. The order of statements is not
- significant.
- </para>
-
- <para>
- The <command>options</command> statement has
- three clauses:
- <command>default-server</command>, <command>default-key</command>,
- and <command>default-port</command>.
- <command>default-server</command> takes a
- host name or address argument and represents the server
- that will
- be contacted if no <option>-s</option>
- option is provided on the command line.
- <command>default-key</command> takes
- the name of a key as its argument, as defined by a <command>key</command> statement.
- <command>default-port</command> specifies the
- port to which
- <command>rndc</command> should connect if no
- port is given on the command line or in a
- <command>server</command> statement.
- </para>
-
- <para>
- The <command>key</command> statement defines a
- key to be used
- by <command>rndc</command> when authenticating
- with
- <command>named</command>. Its syntax is
- identical to the
- <command>key</command> statement in <filename>named.conf</filename>.
- The keyword <userinput>key</userinput> is
- followed by a key name, which must be a valid
- domain name, though it need not actually be hierarchical;
- thus,
- a string like "<userinput>rndc_key</userinput>" is a valid
- name.
- The <command>key</command> statement has two
- clauses:
- <command>algorithm</command> and <command>secret</command>.
- While the configuration parser will accept any string as the
- argument
- to algorithm, currently only the strings
- "<userinput>hmac-md5</userinput>",
- "<userinput>hmac-sha1</userinput>",
- "<userinput>hmac-sha224</userinput>",
- "<userinput>hmac-sha256</userinput>",
- "<userinput>hmac-sha384</userinput>"
- and "<userinput>hmac-sha512</userinput>"
- have any meaning. The secret is a base-64 encoded string
- as specified in RFC 3548.
- </para>
-
- <para>
- The <command>server</command> statement
- associates a key
- defined using the <command>key</command>
- statement with a server.
- The keyword <userinput>server</userinput> is followed by a
- host name or address. The <command>server</command> statement
- has two clauses: <command>key</command> and <command>port</command>.
- The <command>key</command> clause specifies the
- name of the key
- to be used when communicating with this server, and the
- <command>port</command> clause can be used to
- specify the port <command>rndc</command> should
- connect
- to on the server.
- </para>
-
- <para>
- A sample minimal configuration file is as follows:
- </para>
+ </variablelist>
+ </sect3>
-<programlisting>
+ <sect3 id="admin_tools">
+ <title>Administrative Tools</title>
+ <para>
+ Administrative tools play an integral part in the management
+ of a server.
+ </para>
+ <variablelist>
+ <varlistentry id="named-checkconf" xreflabel="Named Configuration Checking application">
+
+ <term><command>named-checkconf</command></term>
+ <listitem>
+ <para>
+ The <command>named-checkconf</command> program
+ checks the syntax of a <filename>named.conf</filename> file.
+ </para>
+ <cmdsynopsis label="Usage">
+ <command>named-checkconf</command>
+ <arg>-jvz</arg>
+ <arg>-t <replaceable>directory</replaceable></arg>
+ <arg><replaceable>filename</replaceable></arg>
+ </cmdsynopsis>
+ </listitem>
+ </varlistentry>
+ <varlistentry id="named-checkzone" xreflabel="Zone Checking application">
+
+ <term><command>named-checkzone</command></term>
+ <listitem>
+ <para>
+ The <command>named-checkzone</command> program
+ checks a master file for
+ syntax and consistency.
+ </para>
+ <cmdsynopsis label="Usage">
+ <command>named-checkzone</command>
+ <arg>-djqvD</arg>
+ <arg>-c <replaceable>class</replaceable></arg>
+ <arg>-o <replaceable>output</replaceable></arg>
+ <arg>-t <replaceable>directory</replaceable></arg>
+ <arg>-w <replaceable>directory</replaceable></arg>
+ <arg>-k <replaceable>(ignore|warn|fail)</replaceable></arg>
+ <arg>-n <replaceable>(ignore|warn|fail)</replaceable></arg>
+ <arg>-W <replaceable>(ignore|warn)</replaceable></arg>
+ <arg choice="plain"><replaceable>zone</replaceable></arg>
+ <arg><replaceable>filename</replaceable></arg>
+ </cmdsynopsis>
+ </listitem>
+ </varlistentry>
+ <varlistentry id="named-compilezone" xreflabel="Zone Compilation application">
+ <term><command>named-compilezone</command></term>
+ <listitem>
+ <para>
+ Similar to <command>named-checkzone,</command> but
+ it always dumps the zone content to a specified file
+ (typically in a different format).
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry id="rndc" xreflabel="Remote Name Daemon Control application">
+
+ <term><command>rndc</command></term>
+ <listitem>
+ <para>
+ The remote name daemon control
+ (<command>rndc</command>) program allows the
+ system
+ administrator to control the operation of a name server.
+ Since <acronym>BIND</acronym> 9.2, <command>rndc</command>
+ supports all the commands of the BIND 8 <command>ndc</command>
+ utility except <command>ndc start</command> and
+ <command>ndc restart</command>, which were also
+ not supported in <command>ndc</command>'s
+ channel mode.
+ If you run <command>rndc</command> without any
+ options
+ it will display a usage message as follows:
+ </para>
+ <cmdsynopsis label="Usage">
+ <command>rndc</command>
+ <arg>-c <replaceable>config</replaceable></arg>
+ <arg>-s <replaceable>server</replaceable></arg>
+ <arg>-p <replaceable>port</replaceable></arg>
+ <arg>-y <replaceable>key</replaceable></arg>
+ <arg choice="plain"><replaceable>command</replaceable></arg>
+ <arg rep="repeat"><replaceable>command</replaceable></arg>
+ </cmdsynopsis>
+
+ <para>See <xref linkend="man.rndc"/> for details of
+ the available <command>rndc</command> commands.
+ </para>
+
+ <para>
+ <command>rndc</command> requires a configuration file,
+ since all
+ communication with the server is authenticated with
+ digital signatures that rely on a shared secret, and
+ there is no way to provide that secret other than with a
+ configuration file. The default location for the
+ <command>rndc</command> configuration file is
+ <filename>/etc/rndc.conf</filename>, but an
+ alternate
+ location can be specified with the <option>-c</option>
+ option. If the configuration file is not found,
+ <command>rndc</command> will also look in
+ <filename>/etc/rndc.key</filename> (or whatever
+ <varname>sysconfdir</varname> was defined when
+ the <acronym>BIND</acronym> build was
+ configured).
+ The <filename>rndc.key</filename> file is
+ generated by
+ running <command>rndc-confgen -a</command> as
+ described in
+ <xref linkend="controls_statement_definition_and_usage"/>.
+ </para>
+
+ <para>
+ The format of the configuration file is similar to
+ that of <filename>named.conf</filename>, but
+ limited to
+ only four statements, the <command>options</command>,
+ <command>key</command>, <command>server</command> and
+ <command>include</command>
+ statements. These statements are what associate the
+ secret keys to the servers with which they are meant to
+ be shared. The order of statements is not
+ significant.
+ </para>
+
+ <para>
+ The <command>options</command> statement has
+ three clauses:
+ <command>default-server</command>, <command>default-key</command>,
+ and <command>default-port</command>.
+ <command>default-server</command> takes a
+ host name or address argument and represents the server
+ that will
+ be contacted if no <option>-s</option>
+ option is provided on the command line.
+ <command>default-key</command> takes
+ the name of a key as its argument, as defined by a <command>key</command> statement.
+ <command>default-port</command> specifies the
+ port to which
+ <command>rndc</command> should connect if no
+ port is given on the command line or in a
+ <command>server</command> statement.
+ </para>
+
+ <para>
+ The <command>key</command> statement defines a
+ key to be used
+ by <command>rndc</command> when authenticating
+ with
+ <command>named</command>. Its syntax is
+ identical to the
+ <command>key</command> statement in <filename>named.conf</filename>.
+ The keyword <userinput>key</userinput> is
+ followed by a key name, which must be a valid
+ domain name, though it need not actually be hierarchical;
+ thus,
+ a string like "<userinput>rndc_key</userinput>" is a valid
+ name.
+ The <command>key</command> statement has two
+ clauses:
+ <command>algorithm</command> and <command>secret</command>.
+ While the configuration parser will accept any string as the
+ argument
+ to algorithm, currently only the strings
+ "<userinput>hmac-md5</userinput>",
+ "<userinput>hmac-sha1</userinput>",
+ "<userinput>hmac-sha224</userinput>",
+ "<userinput>hmac-sha256</userinput>",
+ "<userinput>hmac-sha384</userinput>"
+ and "<userinput>hmac-sha512</userinput>"
+ have any meaning. The secret is a base-64 encoded string
+ as specified in RFC 3548.
+ </para>
+
+ <para>
+ The <command>server</command> statement
+ associates a key
+ defined using the <command>key</command>
+ statement with a server.
+ The keyword <userinput>server</userinput> is followed by a
+ host name or address. The <command>server</command> statement
+ has two clauses: <command>key</command> and <command>port</command>.
+ The <command>key</command> clause specifies the
+ name of the key
+ to be used when communicating with this server, and the
+ <command>port</command> clause can be used to
+ specify the port <command>rndc</command> should
+ connect
+ to on the server.
+ </para>
+
+ <para>
+ A sample minimal configuration file is as follows:
+ </para>
+
+<programlisting>
key rndc_key {
algorithm "hmac-sha256";
secret
};
</programlisting>
- This file, if installed as <filename>/etc/rndc.conf</filename>,
- would allow the command:
- </para>
+ <para>
+ This file, if installed as <filename>/etc/rndc.conf</filename>,
+ would allow the command:
+ </para>
-
<prompt>$ </prompt><userinput>rndc reload</userinput>
- </para>
+ <para>
+ <prompt>$ </prompt><userinput>rndc reload</userinput>
+ </para>
- to connect to 127.0.0.1 port 953 and cause the name server
- to reload, if a name server on the local machine were
- running with
- following controls statements:
- </para>
+ <para>
+ to connect to 127.0.0.1 port 953 and cause the name server
+ to reload, if a name server on the local machine were
+ running with
+ following controls statements:
+ </para>
<programlisting>
controls {
- inet 127.0.0.1
- allow { localhost; } keys { rndc_key; };
+ inet 127.0.0.1
+ allow { localhost; } keys { rndc_key; };
};
</programlisting>
- and it had an identical key statement for
- <literal>rndc_key</literal>.
- </para>
-
- Running the <command>rndc-confgen</command>
- program will
- conveniently create a <filename>rndc.conf</filename>
- file for you, and also display the
- corresponding <command>controls</command>
- statement that you need to
- add to <filename>named.conf</filename>.
- Alternatively,
- you can run <command>rndc-confgen -a</command>
- to set up
- a <filename>rndc.key</filename> file and not
- modify
- <filename>named.conf</filename> at all.
- </para>
-
- </listitem>
- </varlistentry>
- </variablelist>
-
- </sect3>
+ <para>
+ and it had an identical key statement for
+ <literal>rndc_key</literal>.
+ </para>
+
+ <para>
+ Running the <command>rndc-confgen</command>
+ program will
+ conveniently create a <filename>rndc.conf</filename>
+ file for you, and also display the
+ corresponding <command>controls</command>
+ statement that you need to
+ add to <filename>named.conf</filename>.
+ Alternatively,
+ you can run <command>rndc-confgen -a</command>
+ to set up
+ a <filename>rndc.key</filename> file and not
+ modify
+ <filename>named.conf</filename> at all.
+ </para>
+
+ </listitem>
+ </varlistentry>
+ </variablelist>
+
+ </sect3>
</sect2>
<sect2>
- <title>Signals</title>
- Certain UNIX signals cause the name server to take specific
- actions, as described in the following table. These signals can
- be sent using the <command>kill</command> command.
- </para>
- <informaltable frame="all">
- <tgroup cols="2">
- <colspec colname="1" colnum="1" colsep="0" colwidth="1.125in"/>
- <colspec colname="2" colnum="2" colsep="0" colwidth="4.000in"/>
- <tbody>
- <row rowsep="0">
- <entry colname="1">
-
<para><command>SIGHUP</command></para>
- </entry>
- <entry colname="2">
- Causes the server to read <filename>named.conf</filename> and
- reload the database.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
-
<para><command>SIGTERM</command></para>
- </entry>
- <entry colname="2">
- Causes the server to clean up and exit.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
-
<para><command>SIGINT</command></para>
- </entry>
- <entry colname="2">
- Causes the server to clean up and exit.
- </para>
- </entry>
- </row>
- </tbody>
- </tgroup>
- </informaltable>
+ <title>Signals</title>
+ <para>
+ Certain UNIX signals cause the name server to take specific
+ actions, as described in the following table. These signals can
+ be sent using the <command>kill</command> command.
+ </para>
+ <informaltable frame="all">
+ <tgroup cols="2">
+ <colspec colname="1" colnum="1" colsep="0" colwidth="1.125in"/>
+ <colspec colname="2" colnum="2" colsep="0" colwidth="4.000in"/>
+ <tbody>
+ <row rowsep="0">
+ <entry colname="1">
+ <para><command>SIGHUP</command></para>
+ </entry>
+ <entry colname="2">
+ <para>
+ Causes the server to read <filename>named.conf</filename> and
+ reload the database.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para><command>SIGTERM</command></para>
+ </entry>
+ <entry colname="2">
+ <para>
+ Causes the server to clean up and exit.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para><command>SIGINT</command></para>
+ </entry>
+ <entry colname="2">
+ <para>
+ Causes the server to clean up and exit.
+ </para>
+ </entry>
+ </row>
+ </tbody>
+ </tgroup>
+ </informaltable>
</sect2>
</sect1>
</chapter>
<title>Notify</title>
<para>
-
<acronym>DNS</acronym> NOTIFY is a mechanism that allows master
- servers to notify their slave servers of changes to a zone's data. In
- response to a <command>NOTIFY</command> from a master server, the
- slave will check to see that its version of the zone is the
- current version and, if not, initiate a zone transfer.
+ <acronym>DNS</acronym> NOTIFY is a mechanism that allows master
+ servers to notify their slave servers of changes to a zone's data. In
+ response to a <command>NOTIFY</command> from a master server, the
+ slave will check to see that its version of the zone is the
+ current version and, if not, initiate a zone transfer.
</para>
<para>
-
For more information about <acronym>DNS</acronym>
- <command>NOTIFY</command>, see the description of the
- <command>notify</command> option in <xref linkend="boolean_options"/> and
- the description of the zone option <command>also-notify</command> in
- <xref linkend="zone_transfers"/>. The <command>NOTIFY</command>
- protocol is specified in RFC 1996.
+ For more information about <acronym>DNS</acronym>
+ <command>NOTIFY</command>, see the description of the
+ <command>notify</command> option in <xref linkend="boolean_options"/> and
+ the description of the zone option <command>also-notify</command> in
+ <xref linkend="zone_transfers"/>. The <command>NOTIFY</command>
+ protocol is specified in RFC 1996.
</para>
<note>
As a slave zone can also be a master to other slaves, <command>named</command>,
- by default, sends <command>NOTIFY</command> messages for every zone
+ by default, sends <command>NOTIFY</command> messages for every zone
it loads. Specifying <command>notify master-only;</command> will
cause <command>named</command> to only send <command>NOTIFY</command> for master
zones that it loads.
<title>Dynamic Update</title>
<para>
- Dynamic Update is a method for adding, replacing or deleting
- records in a master server by sending it a special form of DNS
- messages. The format and meaning of these messages is specified
- in RFC 2136.
+ Dynamic Update is a method for adding, replacing or deleting
+ records in a master server by sending it a special form of DNS
+ messages. The format and meaning of these messages is specified
+ in RFC 2136.
</para>
<para>
If the zone's <command>update-policy</command> is set to
<userinput>local</userinput>, updates to the zone
will be permitted for the key <varname>local-ddns</varname>,
- which will be generated by <command>named</command> at startup.
+ which will be generated by <command>named</command> at startup.
See <xref linkend="dynamic_update_policies"/> for more details.
</para>
<sect2 id="journal">
<title>The journal file</title>
- All changes made to a zone using dynamic update are stored
- in the zone's journal file. This file is automatically created
- by the server when the first dynamic update takes place.
- The name of the journal file is formed by appending the extension
- <filename>.jnl</filename> to the name of the
- corresponding zone
- file unless specifically overridden. The journal file is in a
- binary format and should not be edited manually.
- </para>
-
- The server will also occasionally write ("dump")
- the complete contents of the updated zone to its zone file.
- This is not done immediately after
- each dynamic update, because that would be too slow when a large
- zone is updated frequently. Instead, the dump is delayed by
- up to 15 minutes, allowing additional updates to take place.
- During the dump process, transient files will be created
- with the extensions <filename>.jnw</filename> and
- <filename>.jbk</filename>; under ordinary circumstances, these
- will be removed when the dump is complete, and can be safely
- ignored.
- </para>
-
- When a server is restarted after a shutdown or crash, it will replay
- the journal file to incorporate into the zone any updates that
- took
- place after the last zone dump.
- </para>
-
- Changes that result from incoming incremental zone transfers are
- also
- journalled in a similar way.
- </para>
-
- The zone files of dynamic zones cannot normally be edited by
- hand because they are not guaranteed to contain the most recent
- dynamic changes — those are only in the journal file.
- The only way to ensure that the zone file of a dynamic zone
- is up to date is to run <command>rndc stop</command>.
- </para>
-
- If you have to make changes to a dynamic zone
- manually, the following procedure will work: Disable dynamic updates
- to the zone using
- <command>rndc freeze <replaceable>zone</replaceable></command>.
- This will also remove the zone's <filename>.jnl</filename> file
- and update the master file. Edit the zone file. Run
- <command>rndc thaw <replaceable>zone</replaceable></command>
- to reload the changed zone and re-enable dynamic updates.
- </para>
+ <para>
+ All changes made to a zone using dynamic update are stored
+ in the zone's journal file. This file is automatically created
+ by the server when the first dynamic update takes place.
+ The name of the journal file is formed by appending the extension
+ <filename>.jnl</filename> to the name of the
+ corresponding zone
+ file unless specifically overridden. The journal file is in a
+ binary format and should not be edited manually.
+ </para>
+
+ <para>
+ The server will also occasionally write ("dump")
+ the complete contents of the updated zone to its zone file.
+ This is not done immediately after
+ each dynamic update, because that would be too slow when a large
+ zone is updated frequently. Instead, the dump is delayed by
+ up to 15 minutes, allowing additional updates to take place.
+ During the dump process, transient files will be created
+ with the extensions <filename>.jnw</filename> and
+ <filename>.jbk</filename>; under ordinary circumstances, these
+ will be removed when the dump is complete, and can be safely
+ ignored.
+ </para>
+
+ <para>
+ When a server is restarted after a shutdown or crash, it will replay
+ the journal file to incorporate into the zone any updates that
+ took
+ place after the last zone dump.
+ </para>
+
+ <para>
+ Changes that result from incoming incremental zone transfers are
+ also
+ journalled in a similar way.
+ </para>
+
+ <para>
+ The zone files of dynamic zones cannot normally be edited by
+ hand because they are not guaranteed to contain the most recent
+ dynamic changes — those are only in the journal file.
+ The only way to ensure that the zone file of a dynamic zone
+ is up to date is to run <command>rndc stop</command>.
+ </para>
+
+ <para>
+ If you have to make changes to a dynamic zone
+ manually, the following procedure will work: Disable dynamic updates
+ to the zone using
+ <command>rndc freeze <replaceable>zone</replaceable></command>.
+ This will also remove the zone's <filename>.jnl</filename> file
+ and update the master file. Edit the zone file. Run
+ <command>rndc thaw <replaceable>zone</replaceable></command>
+ to reload the changed zone and re-enable dynamic updates.
+ </para>
</sect2>
<title>Incremental Zone Transfers (IXFR)</title>
<para>
- The incremental zone transfer (IXFR) protocol is a way for
- slave servers to transfer only changed data, instead of having to
- transfer the entire zone. The IXFR protocol is specified in RFC
- 1995. See <xref linkend="proposed_standards"/>.
+ The incremental zone transfer (IXFR) protocol is a way for
+ slave servers to transfer only changed data, instead of having to
+ transfer the entire zone. The IXFR protocol is specified in RFC
+ 1995. See <xref linkend="proposed_standards"/>.
</para>
<para>
-
When acting as a master, <acronym>BIND</acronym> 9
- supports IXFR for those zones
- where the necessary change history information is available. These
- include master zones maintained by dynamic update and slave zones
- whose data was obtained by IXFR. For manually maintained master
- zones, and for slave zones obtained by performing a full zone
- transfer (AXFR), IXFR is supported only if the option
- <command>ixfr-from-differences</command> is set
- to <userinput>yes</userinput>.
+ When acting as a master, <acronym>BIND</acronym> 9
+ supports IXFR for those zones
+ where the necessary change history information is available. These
+ include master zones maintained by dynamic update and slave zones
+ whose data was obtained by IXFR. For manually maintained master
+ zones, and for slave zones obtained by performing a full zone
+ transfer (AXFR), IXFR is supported only if the option
+ <command>ixfr-from-differences</command> is set
+ to <userinput>yes</userinput>.
</para>
<para>
-
When acting as a slave, <acronym>BIND</acronym> 9 will
- attempt to use IXFR unless
- it is explicitly disabled. For more information about disabling
- IXFR, see the description of the <command>request-ixfr</command> clause
- of the <command>server</command> statement.
+ When acting as a slave, <acronym>BIND</acronym> 9 will
+ attempt to use IXFR unless
+ it is explicitly disabled. For more information about disabling
+ IXFR, see the description of the <command>request-ixfr</command> clause
+ of the <command>server</command> statement.
</para>
</sect1>
<sect1>
<title>Split DNS</title>
<para>
- Setting up different views, or visibility, of the DNS space to
- internal and external resolvers is usually referred to as a
+ Setting up different views, or visibility, of the DNS space to
+ internal and external resolvers is usually referred to as a
<emphasis>Split DNS</emphasis> setup. There are several
- reasons an organization would want to set up its DNS this way.
+ reasons an organization would want to set up its DNS this way.
</para>
<para>
- One common reason for setting up a DNS system this way is
- to hide "internal" DNS information from "external" clients on the
- Internet. There is some debate as to whether or not this is actually
- useful.
- Internal DNS information leaks out in many ways (via email headers,
- for example) and most savvy "attackers" can find the information
- they need using other means.
+ One common reason for setting up a DNS system this way is
+ to hide "internal" DNS information from "external" clients on the
+ Internet. There is some debate as to whether or not this is actually
+ useful.
+ Internal DNS information leaks out in many ways (via email headers,
+ for example) and most savvy "attackers" can find the information
+ they need using other means.
However, since listing addresses of internal servers that
- external clients cannot possibly reach can result in
- connection delays and other annoyances, an organization may
- choose to use a Split DNS to present a consistent view of itself
- to the outside world.
+ external clients cannot possibly reach can result in
+ connection delays and other annoyances, an organization may
+ choose to use a Split DNS to present a consistent view of itself
+ to the outside world.
</para>
<para>
- Another common reason for setting up a Split DNS system is
- to allow internal networks that are behind filters or in RFC 1918
- space (reserved IP space, as documented in RFC 1918) to resolve DNS
- on the Internet. Split DNS can also be used to allow mail from outside
- back in to the internal network.
+ Another common reason for setting up a Split DNS system is
+ to allow internal networks that are behind filters or in RFC 1918
+ space (reserved IP space, as documented in RFC 1918) to resolve DNS
+ on the Internet. Split DNS can also be used to allow mail from outside
+ back in to the internal network.
</para>
<sect2>
<title>Example split DNS setup</title>
<para>
- Let's say a company named <emphasis>Example, Inc.</emphasis>
- (<literal>example.com</literal>)
- has several corporate sites that have an internal network with
- reserved
- Internet Protocol (IP) space and an external demilitarized zone (DMZ),
- or "outside" section of a network, that is available to the public.
+ Let's say a company named <emphasis>Example, Inc.</emphasis>
+ (<literal>example.com</literal>)
+ has several corporate sites that have an internal network with
+ reserved
+ Internet Protocol (IP) space and an external demilitarized zone (DMZ),
+ or "outside" section of a network, that is available to the public.
</para>
<para>
- <emphasis>Example, Inc.</emphasis> wants its internal clients
- to be able to resolve external hostnames and to exchange mail with
- people on the outside. The company also wants its internal resolvers
- to have access to certain internal-only zones that are not available
- at all outside of the internal network.
+ <emphasis>Example, Inc.</emphasis> wants its internal clients
+ to be able to resolve external hostnames and to exchange mail with
+ people on the outside. The company also wants its internal resolvers
+ to have access to certain internal-only zones that are not available
+ at all outside of the internal network.
</para>
<para>
- In order to accomplish this, the company will set up two sets
- of name servers. One set will be on the inside network (in the
- reserved
- IP space) and the other set will be on bastion hosts, which are
- "proxy"
- hosts that can talk to both sides of its network, in the DMZ.
+ In order to accomplish this, the company will set up two sets
+ of name servers. One set will be on the inside network (in the
+ reserved
+ IP space) and the other set will be on bastion hosts, which are
+ "proxy"
+ hosts that can talk to both sides of its network, in the DMZ.
</para>
<para>
- The internal servers will be configured to forward all queries,
- except queries for <filename>site1.internal</filename>, <filename>site2.internal</filename>, <filename>site1.example.com</filename>,
- and <filename>site2.example.com</filename>, to the servers
- in the
- DMZ. These internal servers will have complete sets of information
- for <filename>site1.example.com</filename>, <filename>site2.example.com</filename>, <filename>site1.internal</filename>,
- and <filename>site2.internal</filename>.
+ The internal servers will be configured to forward all queries,
+ except queries for <filename>site1.internal</filename>, <filename>site2.internal</filename>, <filename>site1.example.com</filename>,
+ and <filename>site2.example.com</filename>, to the servers
+ in the
+ DMZ. These internal servers will have complete sets of information
+ for <filename>site1.example.com</filename>, <filename>site2.example.com</filename>, <filename>site1.internal</filename>,
+ and <filename>site2.internal</filename>.
</para>
<para>
- To protect the <filename>site1.internal</filename> and <filename>site2.internal</filename> domains,
- the internal name servers must be configured to disallow all queries
- to these domains from any external hosts, including the bastion
- hosts.
+ To protect the <filename>site1.internal</filename> and <filename>site2.internal</filename> domains,
+ the internal name servers must be configured to disallow all queries
+ to these domains from any external hosts, including the bastion
+ hosts.
</para>
<para>
- The external servers, which are on the bastion hosts, will
- be configured to serve the "public" version of the <filename>site1</filename> and <filename>site2.example.com</filename> zones.
- This could include things such as the host records for public servers
- (<filename>www.example.com</filename> and <filename>ftp.example.com</filename>),
- and mail exchange (MX) records (<filename>a.mx.example.com</filename> and <filename>b.mx.example.com</filename>).
+ The external servers, which are on the bastion hosts, will
+ be configured to serve the "public" version of the <filename>site1</filename> and <filename>site2.example.com</filename> zones.
+ This could include things such as the host records for public servers
+ (<filename>www.example.com</filename> and <filename>ftp.example.com</filename>),
+ and mail exchange (MX) records (<filename>a.mx.example.com</filename> and <filename>b.mx.example.com</filename>).
</para>
<para>
- In addition, the public <filename>site1</filename> and <filename>site2.example.com</filename> zones
- should have special MX records that contain wildcard (`*') records
- pointing to the bastion hosts. This is needed because external mail
- servers do not have any other way of looking up how to deliver mail
- to those internal hosts. With the wildcard records, the mail will
- be delivered to the bastion host, which can then forward it on to
- internal hosts.
+ In addition, the public <filename>site1</filename> and <filename>site2.example.com</filename> zones
+ should have special MX records that contain wildcard (`*') records
+ pointing to the bastion hosts. This is needed because external mail
+ servers do not have any other way of looking up how to deliver mail
+ to those internal hosts. With the wildcard records, the mail will
+ be delivered to the bastion host, which can then forward it on to
+ internal hosts.
</para>
<para>
- Here's an example of a wildcard MX record:
+ Here's an example of a wildcard MX record:
</para>
<programlisting>* IN MX 10 external1.example.com.</programlisting>
<para>
- Now that they accept mail on behalf of anything in the internal
- network, the bastion hosts will need to know how to deliver mail
- to internal hosts. In order for this to work properly, the resolvers
- on
- the bastion hosts will need to be configured to point to the internal
- name servers for DNS resolution.
+ Now that they accept mail on behalf of anything in the internal
+ network, the bastion hosts will need to know how to deliver mail
+ to internal hosts. In order for this to work properly, the resolvers
+ on
+ the bastion hosts will need to be configured to point to the internal
+ name servers for DNS resolution.
</para>
<para>
- Queries for internal hostnames will be answered by the internal
- servers, and queries for external hostnames will be forwarded back
- out to the DNS servers on the bastion hosts.
+ Queries for internal hostnames will be answered by the internal
+ servers, and queries for external hostnames will be forwarded back
+ out to the DNS servers on the bastion hosts.
</para>
<para>
- In order for all this to work properly, internal clients will
- need to be configured to query <emphasis>only</emphasis> the internal
- name servers for DNS queries. This could also be enforced via
- selective
- filtering on the network.
+ In order for all this to work properly, internal clients will
+ need to be configured to query <emphasis>only</emphasis> the internal
+ name servers for DNS queries. This could also be enforced via
+ selective
+ filtering on the network.
</para>
<para>
- If everything has been set properly, <emphasis>Example, Inc.</emphasis>'s
- internal clients will now be able to:
+ If everything has been set properly, <emphasis>Example, Inc.</emphasis>'s
+ internal clients will now be able to:
</para>
<itemizedlist>
- <listitem>
- <simpara>
- Look up any hostnames in the <literal>site1</literal>
- and
- <literal>site2.example.com</literal> zones.
- </simpara>
- </listitem>
- <listitem>
- <simpara>
- Look up any hostnames in the <literal>site1.internal</literal> and
- <literal>site2.internal</literal> domains.
- </simpara>
- </listitem>
- <listitem>
- <simpara>Look up any hostnames on the Internet.</simpara>
- </listitem>
- <listitem>
- <simpara>Exchange mail with both internal and external people.</simpara>
- </listitem>
+ <listitem>
+ <simpara>
+ Look up any hostnames in the <literal>site1</literal>
+ and
+ <literal>site2.example.com</literal> zones.
+ </simpara>
+ </listitem>
+ <listitem>
+ <simpara>
+ Look up any hostnames in the <literal>site1.internal</literal> and
+ <literal>site2.internal</literal> domains.
+ </simpara>
+ </listitem>
+ <listitem>
+ <simpara>Look up any hostnames on the Internet.</simpara>
+ </listitem>
+ <listitem>
+ <simpara>Exchange mail with both internal and external people.</simpara>
+ </listitem>
</itemizedlist>
<para>
- Hosts on the Internet will be able to:
+ Hosts on the Internet will be able to:
</para>
<itemizedlist>
- <listitem>
- <simpara>
- Look up any hostnames in the <literal>site1</literal>
- and
- <literal>site2.example.com</literal> zones.
- </simpara>
- </listitem>
- <listitem>
- <simpara>
- Exchange mail with anyone in the <literal>site1</literal> and
- <literal>site2.example.com</literal> zones.
- </simpara>
- </listitem>
+ <listitem>
+ <simpara>
+ Look up any hostnames in the <literal>site1</literal>
+ and
+ <literal>site2.example.com</literal> zones.
+ </simpara>
+ </listitem>
+ <listitem>
+ <simpara>
+ Exchange mail with anyone in the <literal>site1</literal> and
+ <literal>site2.example.com</literal> zones.
+ </simpara>
+ </listitem>
</itemizedlist>
<para>
- Here is an example configuration for the setup we just
- described above. Note that this is only configuration information;
- for information on how to configure your zone files, see <xref linkend="sample_configuration"/>.
+ Here is an example configuration for the setup we just
+ described above. Note that this is only configuration information;
+ for information on how to configure your zone files, see <xref linkend="sample_configuration"/>.
</para>
<para>
- Internal DNS server config:
+ Internal DNS server config:
</para>
<programlisting>
forward only;
// forward to external servers
forwarders {
- <varname>bastion-ips-go-here</varname>;
+ <varname>bastion-ips-go-here</varname>;
};
// sample allow-transfer (no one)
allow-transfer { none; };
</programlisting>
<para>
- External (bastion host) DNS server config:
+ External (bastion host) DNS server config:
</para>
<programlisting>
</programlisting>
<para>
- In the <filename>resolv.conf</filename> (or equivalent) on
- the bastion host(s):
+ In the <filename>resolv.conf</filename> (or equivalent) on
+ the bastion host(s):
</para>
<programlisting>
<sect1 id="tsig">
<title>TSIG</title>
<para>
- This is a short guide to setting up Transaction SIGnatures
-
(TSIG) based transaction security in <acronym>BIND</acronym>. It describes changes
- to the configuration file as well as what changes are required for
- different features, including the process of creating transaction
-
keys and using transaction signatures with <acronym>BIND</acronym>.
+ This is a short guide to setting up Transaction SIGnatures
+ (TSIG) based transaction security in <acronym>BIND</acronym>. It describes changes
+ to the configuration file as well as what changes are required for
+ different features, including the process of creating transaction
+ keys and using transaction signatures with <acronym>BIND</acronym>.
</para>
<para>
-
<acronym>BIND</acronym> primarily supports TSIG for server
- to server communication.
- This includes zone transfer, notify, and recursive query messages.
-
Resolvers based on newer versions of <acronym>BIND</acronym> 8 have limited support
- for TSIG.
+ <acronym>BIND</acronym> primarily supports TSIG for server
+ to server communication.
+ This includes zone transfer, notify, and recursive query messages.
+ Resolvers based on newer versions of <acronym>BIND</acronym> 8 have limited support
+ for TSIG.
</para>
<para>
- TSIG can also be useful for dynamic update. A primary
- server for a dynamic zone should control access to the dynamic
- update service, but IP-based access control is insufficient.
- The cryptographic access control provided by TSIG
- is far superior. The <command>nsupdate</command>
- program supports TSIG via the <option>-k</option> and
- <option>-y</option> command line options or inline by use
+ TSIG can also be useful for dynamic update. A primary
+ server for a dynamic zone should control access to the dynamic
+ update service, but IP-based access control is insufficient.
+ The cryptographic access control provided by TSIG
+ is far superior. The <command>nsupdate</command>
+ program supports TSIG via the <option>-k</option> and
+ <option>-y</option> command line options or inline by use
of the <command>key</command>.
</para>
<sect2>
- <title>Generate Shared Keys for Each Pair of Hosts</title>
- A shared secret is generated to be shared between <emphasis>host1</emphasis> and <emphasis>host2</emphasis>.
- An arbitrary key name is chosen: "host1-host2.". The key name must
- be the same on both hosts.
- </para>
- <sect3>
- <title>Automatic Generation</title>
- The following command will generate a 128-bit (16 byte) HMAC-SHA256
- key as described above. Longer keys are better, but shorter keys
- are easier to read. Note that the maximum key length is the digest
- length, here 256 bits.
- </para>
- <userinput>dnssec-keygen -a hmac-sha256 -b 128 -n HOST host1-host2.</userinput>
- </para>
- The key is in the file <filename>Khost1-host2.+163+00000.private</filename>.
- Nothing directly uses this file, but the base-64 encoded string
- following "<literal>Key:</literal>"
- can be extracted from the file and used as a shared secret:
- </para>
-
<programlisting>Key: La/E5CjG9O+os1jq0a2jdA==</programlisting>
- The string "<literal>La/E5CjG9O+os1jq0a2jdA==</literal>" can
- be used as the shared secret.
- </para>
- </sect3>
- <sect3>
- <title>Manual Generation</title>
- The shared secret is simply a random sequence of bits, encoded
- in base-64. Most ASCII strings are valid base-64 strings (assuming
- the length is a multiple of 4 and only valid characters are used),
- so the shared secret can be manually generated.
- </para>
- Also, a known string can be run through <command>mmencode</command> or
- a similar program to generate base-64 encoded data.
- </para>
- </sect3>
+ <title>Generate Shared Keys for Each Pair of Hosts</title>
+ <para>
+ A shared secret is generated to be shared between <emphasis>host1</emphasis> and <emphasis>host2</emphasis>.
+ An arbitrary key name is chosen: "host1-host2.". The key name must
+ be the same on both hosts.
+ </para>
+ <sect3>
+ <title>Automatic Generation</title>
+ <para>
+ The following command will generate a 128-bit (16 byte) HMAC-SHA256
+ key as described above. Longer keys are better, but shorter keys
+ are easier to read. Note that the maximum key length is the digest
+ length, here 256 bits.
+ </para>
+ <para>
+ <userinput>dnssec-keygen -a hmac-sha256 -b 128 -n HOST host1-host2.</userinput>
+ </para>
+ <para>
+ The key is in the file <filename>Khost1-host2.+163+00000.private</filename>.
+ Nothing directly uses this file, but the base-64 encoded string
+ following "<literal>Key:</literal>"
+ can be extracted from the file and used as a shared secret:
+ </para>
+ <programlisting>Key: La/E5CjG9O+os1jq0a2jdA==</programlisting>
+ <para>
+ The string "<literal>La/E5CjG9O+os1jq0a2jdA==</literal>" can
+ be used as the shared secret.
+ </para>
+ </sect3>
+ <sect3>
+ <title>Manual Generation</title>
+ <para>
+ The shared secret is simply a random sequence of bits, encoded
+ in base-64. Most ASCII strings are valid base-64 strings (assuming
+ the length is a multiple of 4 and only valid characters are used),
+ so the shared secret can be manually generated.
+ </para>
+ <para>
+ Also, a known string can be run through <command>mmencode</command> or
+ a similar program to generate base-64 encoded data.
+ </para>
+ </sect3>
</sect2>
<sect2>
- <title>Copying the Shared Secret to Both Machines</title>
- This is beyond the scope of DNS. A secure transport mechanism
- should be used. This could be secure FTP, ssh, telephone, etc.
- </para>
+ <title>Copying the Shared Secret to Both Machines</title>
+ <para>
+ This is beyond the scope of DNS. A secure transport mechanism
+ should be used. This could be secure FTP, ssh, telephone, etc.
+ </para>
</sect2>
<sect2>
- <title>Informing the Servers of the Key's Existence</title>
- Imagine <emphasis>host1</emphasis> and <emphasis>host 2</emphasis>
- are
- both servers. The following is added to each server's <filename>named.conf</filename> file:
- </para>
+ <title>Informing the Servers of the Key's Existence</title>
+ <para>
+ Imagine <emphasis>host1</emphasis> and <emphasis>host 2</emphasis>
+ are
+ both servers. The following is added to each server's <filename>named.conf</filename> file:
+ </para>
<programlisting>
key host1-host2. {
};
</programlisting>
- The secret is the one generated above. Since this is a secret, it
- is recommended that either <filename>named.conf</filename> be
- non-world readable, or the key directive be added to a non-world
- readable file that is included by <filename>named.conf</filename>.
- </para>
- At this point, the key is recognized. This means that if the
- server receives a message signed by this key, it can verify the
- signature. If the signature is successfully verified, the
- response is signed by the same key.
- </para>
+ <para>
+ The secret is the one generated above. Since this is a secret, it
+ is recommended that either <filename>named.conf</filename> be
+ non-world readable, or the key directive be added to a non-world
+ readable file that is included by <filename>named.conf</filename>.
+ </para>
+ <para>
+ At this point, the key is recognized. This means that if the
+ server receives a message signed by this key, it can verify the
+ signature. If the signature is successfully verified, the
+ response is signed by the same key.
+ </para>
</sect2>
<sect2>
- <title>Instructing the Server to Use the Key</title>
- Since keys are shared between two hosts only, the server must
- be told when keys are to be used. The following is added to the <filename>named.conf</filename> file
- for <emphasis>host1</emphasis>, if the IP address of <emphasis>host2</emphasis> is
- 10.1.2.3:
- </para>
+ <title>Instructing the Server to Use the Key</title>
+ <para>
+ Since keys are shared between two hosts only, the server must
+ be told when keys are to be used. The following is added to the <filename>named.conf</filename> file
+ for <emphasis>host1</emphasis>, if the IP address of <emphasis>host2</emphasis> is
+ 10.1.2.3:
+ </para>
<programlisting>
server 10.1.2.3 {
};
</programlisting>
- Multiple keys may be present, but only the first is used.
- This directive does not contain any secrets, so it may be in a
- world-readable
- file.
- </para>
- If <emphasis>host1</emphasis> sends a message that is a request
- to that address, the message will be signed with the specified key. <emphasis>host1</emphasis> will
- expect any responses to signed messages to be signed with the same
- key.
- </para>
- A similar statement must be present in <emphasis>host2</emphasis>'s
- configuration file (with <emphasis>host1</emphasis>'s address) for <emphasis>host2</emphasis> to
- sign request messages to <emphasis>host1</emphasis>.
- </para>
+ <para>
+ Multiple keys may be present, but only the first is used.
+ This directive does not contain any secrets, so it may be in a
+ world-readable
+ file.
+ </para>
+ <para>
+ If <emphasis>host1</emphasis> sends a message that is a request
+ to that address, the message will be signed with the specified key. <emphasis>host1</emphasis> will
+ expect any responses to signed messages to be signed with the same
+ key.
+ </para>
+ <para>
+ A similar statement must be present in <emphasis>host2</emphasis>'s
+ configuration file (with <emphasis>host1</emphasis>'s address) for <emphasis>host2</emphasis> to
+ sign request messages to <emphasis>host1</emphasis>.
+ </para>
</sect2>
<sect2>
- <title>TSIG Key Based Access Control</title>
-
<acronym>BIND</acronym> allows IP addresses and ranges
- to be specified in ACL
- definitions and
- <command>allow-{ query | transfer | update }</command>
- directives.
- This has been extended to allow TSIG keys also. The above key would
- be denoted <command>key host1-host2.</command>
- </para>
- An example of an <command>allow-update</command> directive would be:
- </para>
+ <title>TSIG Key Based Access Control</title>
+ <para>
+ <acronym>BIND</acronym> allows IP addresses and ranges
+ to be specified in ACL
+ definitions and
+ <command>allow-{ query | transfer | update }</command>
+ directives.
+ This has been extended to allow TSIG keys also. The above key would
+ be denoted <command>key host1-host2.</command>
+ </para>
+ <para>
+ An example of an <command>allow-update</command> directive would be:
+ </para>
<programlisting>
allow-update { key host1-host2. ;};
<para>
See <xref linkend="dynamic_update_policies"/> for a discussion of
- the more flexible <command>update-policy</command> statement.
+ the more flexible <command>update-policy</command> statement.
</para>
</sect2>
<sect2>
- <title>Errors</title>
-
- The processing of TSIG signed messages can result in
- several errors. If a signed message is sent to a non-TSIG aware
- server, a FORMERR (format error) will be returned, since the server will not
- understand the record. This is a result of misconfiguration,
- since the server must be explicitly configured to send a TSIG
- signed message to a specific server.
- </para>
-
- If a TSIG aware server receives a message signed by an
- unknown key, the response will be unsigned with the TSIG
- extended error code set to BADKEY. If a TSIG aware server
- receives a message with a signature that does not validate, the
- response will be unsigned with the TSIG extended error code set
- to BADSIG. If a TSIG aware server receives a message with a time
- outside of the allowed range, the response will be signed with
- the TSIG extended error code set to BADTIME, and the time values
- will be adjusted so that the response can be successfully
- verified. In any of these cases, the message's rcode (response code) is set to
- NOTAUTH (not authenticated).
- </para>
+ <title>Errors</title>
+
+ <para>
+ The processing of TSIG signed messages can result in
+ several errors. If a signed message is sent to a non-TSIG aware
+ server, a FORMERR (format error) will be returned, since the server will not
+ understand the record. This is a result of misconfiguration,
+ since the server must be explicitly configured to send a TSIG
+ signed message to a specific server.
+ </para>
+
+ <para>
+ If a TSIG aware server receives a message signed by an
+ unknown key, the response will be unsigned with the TSIG
+ extended error code set to BADKEY. If a TSIG aware server
+ receives a message with a signature that does not validate, the
+ response will be unsigned with the TSIG extended error code set
+ to BADSIG. If a TSIG aware server receives a message with a time
+ outside of the allowed range, the response will be signed with
+ the TSIG extended error code set to BADTIME, and the time values
+ will be adjusted so that the response can be successfully
+ verified. In any of these cases, the message's rcode (response code) is set to
+ NOTAUTH (not authenticated).
+ </para>
</sect2>
</sect1>
<title>TKEY</title>
<para><command>TKEY</command>
- is a mechanism for automatically generating a shared secret
- between two hosts. There are several "modes" of
- <command>TKEY</command> that specify how the key is generated
-
or assigned. <acronym>BIND</acronym> 9 implements only one of
- these modes, the Diffie-Hellman key exchange. Both hosts are
- required to have a Diffie-Hellman KEY record (although this
- record is not required to be present in a zone). The
- <command>TKEY</command> process must use signed messages,
- signed either by TSIG or SIG(0). The result of
- <command>TKEY</command> is a shared secret that can be used to
- sign messages with TSIG. <command>TKEY</command> can also be
- used to delete shared secrets that it had previously
- generated.
+ is a mechanism for automatically generating a shared secret
+ between two hosts. There are several "modes" of
+ <command>TKEY</command> that specify how the key is generated
+ or assigned. <acronym>BIND</acronym> 9 implements only one of
+ these modes, the Diffie-Hellman key exchange. Both hosts are
+ required to have a Diffie-Hellman KEY record (although this
+ record is not required to be present in a zone). The
+ <command>TKEY</command> process must use signed messages,
+ signed either by TSIG or SIG(0). The result of
+ <command>TKEY</command> is a shared secret that can be used to
+ sign messages with TSIG. <command>TKEY</command> can also be
+ used to delete shared secrets that it had previously
+ generated.
</para>
<para>
- The <command>TKEY</command> process is initiated by a
- client
- or server by sending a signed <command>TKEY</command>
- query
- (including any appropriate KEYs) to a TKEY-aware server. The
- server response, if it indicates success, will contain a
- <command>TKEY</command> record and any appropriate keys.
- After
- this exchange, both participants have enough information to
- determine the shared secret; the exact process depends on the
- <command>TKEY</command> mode. When using the
- Diffie-Hellman
- <command>TKEY</command> mode, Diffie-Hellman keys are
- exchanged,
- and the shared secret is derived by both participants.
+ The <command>TKEY</command> process is initiated by a
+ client
+ or server by sending a signed <command>TKEY</command>
+ query
+ (including any appropriate KEYs) to a TKEY-aware server. The
+ server response, if it indicates success, will contain a
+ <command>TKEY</command> record and any appropriate keys.
+ After
+ this exchange, both participants have enough information to
+ determine the shared secret; the exact process depends on the
+ <command>TKEY</command> mode. When using the
+ Diffie-Hellman
+ <command>TKEY</command> mode, Diffie-Hellman keys are
+ exchanged,
+ and the shared secret is derived by both participants.
</para>
</sect1>
<title>SIG(0)</title>
<para>
-
<acronym>BIND</acronym> 9 partially supports DNSSEC SIG(0)
- transaction signatures as specified in RFC 2535 and RFC 2931.
- SIG(0)
- uses public/private keys to authenticate messages. Access control
- is performed in the same manner as TSIG keys; privileges can be
- granted or denied based on the key name.
+ <acronym>BIND</acronym> 9 partially supports DNSSEC SIG(0)
+ transaction signatures as specified in RFC 2535 and RFC 2931.
+ SIG(0)
+ uses public/private keys to authenticate messages. Access control
+ is performed in the same manner as TSIG keys; privileges can be
+ granted or denied based on the key name.
</para>
<para>
- When a SIG(0) signed message is received, it will only be
- verified if the key is known and trusted by the server; the server
- will not attempt to locate and/or validate the key.
+ When a SIG(0) signed message is received, it will only be
+ verified if the key is known and trusted by the server; the server
+ will not attempt to locate and/or validate the key.
</para>
<para>
- SIG(0) signing of multiple-message TCP streams is not
- supported.
+ SIG(0) signing of multiple-message TCP streams is not
+ supported.
</para>
<para>
-
The only tool shipped with <acronym>BIND</acronym> 9 that
- generates SIG(0) signed messages is <command>nsupdate</command>.
+ The only tool shipped with <acronym>BIND</acronym> 9 that
+ generates SIG(0) signed messages is <command>nsupdate</command>.
</para>
</sect1>
<title>DNSSEC</title>
<para>
- Cryptographic authentication of DNS information is possible
- through the DNS Security (<emphasis>DNSSEC-bis</emphasis>) extensions,
- defined in RFC 4033, RFC 4034, and RFC 4035.
+ Cryptographic authentication of DNS information is possible
+ through the DNS Security (<emphasis>DNSSEC-bis</emphasis>) extensions,
+ defined in RFC 4033, RFC 4034, and RFC 4035.
This section describes the creation and use of DNSSEC signed zones.
</para>
<para>
- In order to set up a DNSSEC secure zone, there are a series
-
of steps which must be followed. <acronym>BIND</acronym>
- 9 ships
- with several tools
- that are used in this process, which are explained in more detail
- below. In all cases, the <option>-h</option> option prints a
- full list of parameters. Note that the DNSSEC tools require the
- keyset files to be in the working directory or the
- directory specified by the <option>-d</option> option, and
- that the tools shipped with BIND 9.2.x and earlier are not compatible
- with the current ones.
+ In order to set up a DNSSEC secure zone, there are a series
+ of steps which must be followed. <acronym>BIND</acronym>
+ 9 ships
+ with several tools
+ that are used in this process, which are explained in more detail
+ below. In all cases, the <option>-h</option> option prints a
+ full list of parameters. Note that the DNSSEC tools require the
+ keyset files to be in the working directory or the
+ directory specified by the <option>-d</option> option, and
+ that the tools shipped with BIND 9.2.x and earlier are not compatible
+ with the current ones.
</para>
<para>
- There must also be communication with the administrators of
- the parent and/or child zone to transmit keys. A zone's security
- status must be indicated by the parent zone for a DNSSEC capable
- resolver to trust its data. This is done through the presence
- or absence of a <literal>DS</literal> record at the
- delegation
- point.
+ There must also be communication with the administrators of
+ the parent and/or child zone to transmit keys. A zone's security
+ status must be indicated by the parent zone for a DNSSEC capable
+ resolver to trust its data. This is done through the presence
+ or absence of a <literal>DS</literal> record at the
+ delegation
+ point.
</para>
<para>
- For other servers to trust data in this zone, they must
- either be statically configured with this zone's zone key or the
- zone key of another zone above this one in the DNS tree.
+ For other servers to trust data in this zone, they must
+ either be statically configured with this zone's zone key or the
+ zone key of another zone above this one in the DNS tree.
</para>
<sect2>
- <title>Generating Keys</title>
-
- The <command>dnssec-keygen</command> program is used to
- generate keys.
- </para>
-
- A secure zone must contain one or more zone keys. The
- zone keys will sign all other records in the zone, as well as
- the zone keys of any secure delegated zones. Zone keys must
- have the same name as the zone, a name type of
- <command>ZONE</command>, and must be usable for
- authentication.
- It is recommended that zone keys use a cryptographic algorithm
- designated as "mandatory to implement" by the IETF; currently
- the only one is RSASHA1.
- </para>
-
- The following command will generate a 768-bit RSASHA1 key for
- the <filename>child.example</filename> zone:
- </para>
-
- <userinput>dnssec-keygen -a RSASHA1 -b 768 -n ZONE child.example.</userinput>
- </para>
-
- Two output files will be produced:
- <filename>Kchild.example.+005+12345.key</filename> and
- <filename>Kchild.example.+005+12345.private</filename>
- (where
- 12345 is an example of a key tag). The key filenames contain
- the key name (<filename>child.example.</filename>),
- algorithm (3
- is DSA, 1 is RSAMD5, 5 is RSASHA1, etc.), and the key tag (12345 in
- this case).
- The private key (in the <filename>.private</filename>
- file) is
- used to generate signatures, and the public key (in the
- <filename>.key</filename> file) is used for signature
- verification.
- </para>
-
- To generate another key with the same properties (but with
- a different key tag), repeat the above command.
- </para>
-
- The <command>dnssec-keyfromlabel</command> program is used
- to get a key pair from a crypto hardware and build the key
- files. Its usage is similar to <command>dnssec-keygen</command>.
- </para>
-
- The public keys should be inserted into the zone file by
- including the <filename>.key</filename> files using
- <command>$INCLUDE</command> statements.
- </para>
+ <title>Generating Keys</title>
+
+ <para>
+ The <command>dnssec-keygen</command> program is used to
+ generate keys.
+ </para>
+
+ <para>
+ A secure zone must contain one or more zone keys. The
+ zone keys will sign all other records in the zone, as well as
+ the zone keys of any secure delegated zones. Zone keys must
+ have the same name as the zone, a name type of
+ <command>ZONE</command>, and must be usable for
+ authentication.
+ It is recommended that zone keys use a cryptographic algorithm
+ designated as "mandatory to implement" by the IETF; currently
+ the only one is RSASHA1.
+ </para>
+
+ <para>
+ The following command will generate a 768-bit RSASHA1 key for
+ the <filename>child.example</filename> zone:
+ </para>
+
+ <para>
+ <userinput>dnssec-keygen -a RSASHA1 -b 768 -n ZONE child.example.</userinput>
+ </para>
+
+ <para>
+ Two output files will be produced:
+ <filename>Kchild.example.+005+12345.key</filename> and
+ <filename>Kchild.example.+005+12345.private</filename>
+ (where
+ 12345 is an example of a key tag). The key filenames contain
+ the key name (<filename>child.example.</filename>),
+ algorithm (3
+ is DSA, 1 is RSAMD5, 5 is RSASHA1, etc.), and the key tag (12345 in
+ this case).
+ The private key (in the <filename>.private</filename>
+ file) is
+ used to generate signatures, and the public key (in the
+ <filename>.key</filename> file) is used for signature
+ verification.
+ </para>
+
+ <para>
+ To generate another key with the same properties (but with
+ a different key tag), repeat the above command.
+ </para>
+
+ <para>
+ The <command>dnssec-keyfromlabel</command> program is used
+ to get a key pair from a crypto hardware and build the key
+ files. Its usage is similar to <command>dnssec-keygen</command>.
+ </para>
+
+ <para>
+ The public keys should be inserted into the zone file by
+ including the <filename>.key</filename> files using
+ <command>$INCLUDE</command> statements.
+ </para>
</sect2>
<sect2>
- <title>Signing the Zone</title>
+ <title>Signing the Zone</title>
<para>
The <command>dnssec-signzone</command> program is used
zones need to be added manually.
</para>
- The following command signs the zone, assuming it is in a
- file called <filename>zone.child.example</filename>. By
- default, all zone keys which have an available private key are
- used to generate signatures.
- </para>
-
- <userinput>dnssec-signzone -o child.example zone.child.example</userinput>
- </para>
-
- One output file is produced:
- <filename>zone.child.example.signed</filename>. This
- file
- should be referenced by <filename>named.conf</filename>
- as the
- input file for the zone.
- </para>
-
-
<para><command>dnssec-signzone</command>
+ <para>
+ The following command signs the zone, assuming it is in a
+ file called <filename>zone.child.example</filename>. By
+ default, all zone keys which have an available private key are
+ used to generate signatures.
+ </para>
+
+ <para>
+ <userinput>dnssec-signzone -o child.example zone.child.example</userinput>
+ </para>
+
+ <para>
+ One output file is produced:
+ <filename>zone.child.example.signed</filename>. This
+ file
+ should be referenced by <filename>named.conf</filename>
+ as the
+ input file for the zone.
+ </para>
+
+ <para><command>dnssec-signzone</command>
will also produce a keyset and dsset files and optionally a
- dlvset file. These are used to provide the parent zone
- administrators with the <literal>DNSKEYs</literal> (or their
- corresponding <literal>DS</literal> records) that are the
- secure entry point to the zone.
- </para>
+ dlvset file. These are used to provide the parent zone
+ administrators with the <literal>DNSKEYs</literal> (or their
+ corresponding <literal>DS</literal> records) that are the
+ secure entry point to the zone.
+ </para>
</sect2>
<sect2>
- <title>Configuring Servers</title>
+ <title>Configuring Servers</title>
<para>
To enable <command>named</command> to respond appropriately
to DNS requests from DNSSEC aware clients,
<command>dnssec-enable</command> must be set to yes.
- (This is the default setting.)
- </para>
+ (This is the default setting.)
+ </para>
<para>
To enable <command>named</command> to validate answers from
other servers, the <command>dnssec-enable</command> option
- must be set to <userinput>yes</userinput>, and the
- <command>dnssec-validation</command> options must be set to
- <userinput>yes</userinput> or <userinput>auto</userinput>.
- </para>
+ must be set to <userinput>yes</userinput>, and the
+ <command>dnssec-validation</command> options must be set to
+ <userinput>yes</userinput> or <userinput>auto</userinput>.
+ </para>
<para>
- If <command>dnssec-validation</command> is set to
- <userinput>auto</userinput>, then a default
- trust anchor for the DNS root zone will be used.
- If it is set to <userinput>yes</userinput>, however,
- then at least one trust anchor must be configured
- with a <command>trusted-keys</command> or
- <command>managed-keys</command> statement in
- <filename>named.conf</filename>, or DNSSEC validation
- will not occur. The default setting is
- <userinput>yes</userinput>.
- </para>
+ If <command>dnssec-validation</command> is set to
+ <userinput>auto</userinput>, then a default
+ trust anchor for the DNS root zone will be used.
+ If it is set to <userinput>yes</userinput>, however,
+ then at least one trust anchor must be configured
+ with a <command>trusted-keys</command> or
+ <command>managed-keys</command> statement in
+ <filename>named.conf</filename>, or DNSSEC validation
+ will not occur. The default setting is
+ <userinput>yes</userinput>.
+ </para>
<para>
<command>trusted-keys</command> are copies of DNSKEY RRs
<para>
<command>managed-keys</command> are trusted keys which are
- automatically kept up to date via RFC 5011 trust anchor
- maintenance.
+ automatically kept up to date via RFC 5011 trust anchor
+ maintenance.
</para>
<para>
<command>trusted-keys</command> and
- <command>managed-keys</command> are described in more detail
+ <command>managed-keys</command> are described in more detail
later in this document.
</para>
more public keys for the root. This allows answers from
outside the organization to be validated. It will also
have several keys for parts of the namespace the organization
- controls. These are here to ensure that <command>named</command>
- is immune to compromises in the DNSSEC components of the security
- of parent zones.
+ controls. These are here to ensure that <command>named</command>
+ is immune to compromises in the DNSSEC components of the security
+ of parent zones.
</para>
<programlisting>
managed-keys {
/* Root Key */
- "." initial-key 257 3 3 "BNY4wrWM1nCfJ+CXd0rVXyYmobt7sEEfK3clRbGaTwS
- JxrGkxJWoZu6I7PzJu/E9gx4UC1zGAHlXKdE4zYIpRh
- aBKnvcC2U9mZhkdUpd1Vso/HAdjNe8LmMlnzY3zy2Xy
- 4klWOADTPzSv9eamj8V18PHGjBLaVtYvk/ln5ZApjYg
- hf+6fElrmLkdaz MQ2OCnACR817DF4BBa7UR/beDHyp
- 5iWTXWSi6XmoJLbG9Scqc7l70KDqlvXR3M/lUUVRbke
- g1IPJSidmK3ZyCllh4XSKbje/45SKucHgnwU5jefMtq
- 66gKodQj+MiA21AfUVe7u99WzTLzY3qlxDhxYQQ20FQ
- 97S+LKUTpQcq27R7AT3/V5hRQxScINqwcz4jYqZD2fQ
- dgxbcDTClU0CRBdiieyLMNzXG3";
+ "." initial-key 257 3 3 "BNY4wrWM1nCfJ+CXd0rVXyYmobt7sEEfK3clRbGaTwS
+ JxrGkxJWoZu6I7PzJu/E9gx4UC1zGAHlXKdE4zYIpRh
+ aBKnvcC2U9mZhkdUpd1Vso/HAdjNe8LmMlnzY3zy2Xy
+ 4klWOADTPzSv9eamj8V18PHGjBLaVtYvk/ln5ZApjYg
+ hf+6fElrmLkdaz MQ2OCnACR817DF4BBa7UR/beDHyp
+ 5iWTXWSi6XmoJLbG9Scqc7l70KDqlvXR3M/lUUVRbke
+ g1IPJSidmK3ZyCllh4XSKbje/45SKucHgnwU5jefMtq
+ 66gKodQj+MiA21AfUVe7u99WzTLzY3qlxDhxYQQ20FQ
+ 97S+LKUTpQcq27R7AT3/V5hRQxScINqwcz4jYqZD2fQ
+ dgxbcDTClU0CRBdiieyLMNzXG3";
};
trusted-keys {
- /* Key for our organization's forward zone */
- example.com. 257 3 5 "AwEAAaxPMcR2x0HbQV4WeZB6oEDX+r0QM6
- 5KbhTjrW1ZaARmPhEZZe3Y9ifgEuq7vZ/z
- GZUdEGNWy+JZzus0lUptwgjGwhUS1558Hb
- 4JKUbbOTcM8pwXlj0EiX3oDFVmjHO444gL
- kBOUKUf/mC7HvfwYH/Be22GnClrinKJp1O
- g4ywzO9WglMk7jbfW33gUKvirTHr25GL7S
- TQUzBb5Usxt8lgnyTUHs1t3JwCY5hKZ6Cq
- FxmAVZP20igTixin/1LcrgX/KMEGd/biuv
- F4qJCyduieHukuY3H4XMAcR+xia2nIUPvm
- /oyWR8BW/hWdzOvnSCThlHf3xiYleDbt/o
- 1OTQ09A0=";
-
- /* Key for our reverse zone. */
- 2.0.192.IN-ADDRPA.NET. 257 3 5 "AQOnS4xn/IgOUpBPJ3bogzwc
- xOdNax071L18QqZnQQQAVVr+i
- LhGTnNGp3HoWQLUIzKrJVZ3zg
- gy3WwNT6kZo6c0tszYqbtvchm
- gQC8CzKojM/W16i6MG/eafGU3
- siaOdS0yOI6BgPsw+YZdzlYMa
- IJGf4M4dyoKIhzdZyQ2bYQrjy
- Q4LB0lC7aOnsMyYKHHYeRvPxj
- IQXmdqgOJGq+vsevG06zW+1xg
- YJh9rCIfnm1GX/KMgxLPG2vXT
- D/RnLX+D3T3UL7HJYHJhAZD5L
- 59VvjSPsZJHeDCUyWYrvPZesZ
- DIRvhDD52SKvbheeTJUm6Ehkz
- ytNN2SN96QRk8j/iI8ib";
+ /* Key for our organization's forward zone */
+ example.com. 257 3 5 "AwEAAaxPMcR2x0HbQV4WeZB6oEDX+r0QM6
+ 5KbhTjrW1ZaARmPhEZZe3Y9ifgEuq7vZ/z
+ GZUdEGNWy+JZzus0lUptwgjGwhUS1558Hb
+ 4JKUbbOTcM8pwXlj0EiX3oDFVmjHO444gL
+ kBOUKUf/mC7HvfwYH/Be22GnClrinKJp1O
+ g4ywzO9WglMk7jbfW33gUKvirTHr25GL7S
+ TQUzBb5Usxt8lgnyTUHs1t3JwCY5hKZ6Cq
+ FxmAVZP20igTixin/1LcrgX/KMEGd/biuv
+ F4qJCyduieHukuY3H4XMAcR+xia2nIUPvm
+ /oyWR8BW/hWdzOvnSCThlHf3xiYleDbt/o
+ 1OTQ09A0=";
+
+ /* Key for our reverse zone. */
+ 2.0.192.IN-ADDRPA.NET. 257 3 5 "AQOnS4xn/IgOUpBPJ3bogzwc
+ xOdNax071L18QqZnQQQAVVr+i
+ LhGTnNGp3HoWQLUIzKrJVZ3zg
+ gy3WwNT6kZo6c0tszYqbtvchm
+ gQC8CzKojM/W16i6MG/eafGU3
+ siaOdS0yOI6BgPsw+YZdzlYMa
+ IJGf4M4dyoKIhzdZyQ2bYQrjy
+ Q4LB0lC7aOnsMyYKHHYeRvPxj
+ IQXmdqgOJGq+vsevG06zW+1xg
+ YJh9rCIfnm1GX/KMgxLPG2vXT
+ D/RnLX+D3T3UL7HJYHJhAZD5L
+ 59VvjSPsZJHeDCUyWYrvPZesZ
+ DIRvhDD52SKvbheeTJUm6Ehkz
+ ytNN2SN96QRk8j/iI8ib";
};
options {
forgery; it rejects the response and logs an error.
</para>
<para>
- The logged error reads "insecurity proof failed" and
- "got insecure response; parent indicates it should be secure".
+ The logged error reads "insecurity proof failed" and
+ "got insecure response; parent indicates it should be secure".
(Prior to BIND 9.7, the logged error was "not insecure".
- This referred to the zone, not the response.)
+ This referred to the zone, not the response.)
</para>
</note>
</sect2>
<title>IPv6 Support in <acronym>BIND</acronym> 9</title>
<para>
-
<acronym>BIND</acronym> 9 fully supports all currently
- defined forms of IPv6 name to address and address to name
- lookups. It will also use IPv6 addresses to make queries when
- running on an IPv6 capable system.
+ <acronym>BIND</acronym> 9 fully supports all currently
+ defined forms of IPv6 name to address and address to name
+ lookups. It will also use IPv6 addresses to make queries when
+ running on an IPv6 capable system.
</para>
<para>
-
For forward lookups, <acronym>BIND</acronym> 9 supports
- only AAAA records. RFC 3363 deprecated the use of A6 records,
- and client-side support for A6 records was accordingly removed
-
from <acronym>BIND</acronym> 9.
-
However, authoritative <acronym>BIND</acronym> 9 name servers still
- load zone files containing A6 records correctly, answer queries
- for A6 records, and accept zone transfer for a zone containing A6
- records.
+ For forward lookups, <acronym>BIND</acronym> 9 supports
+ only AAAA records. RFC 3363 deprecated the use of A6 records,
+ and client-side support for A6 records was accordingly removed
+ from <acronym>BIND</acronym> 9.
+ However, authoritative <acronym>BIND</acronym> 9 name servers still
+ load zone files containing A6 records correctly, answer queries
+ for A6 records, and accept zone transfer for a zone containing A6
+ records.
</para>
<para>
-
For IPv6 reverse lookups, <acronym>BIND</acronym> 9 supports
- the traditional "nibble" format used in the
- <emphasis>ip6.arpa</emphasis> domain, as well as the older, deprecated
- <emphasis>ip6.int</emphasis> domain.
-
Older versions of <acronym>BIND</acronym> 9
- supported the "binary label" (also known as "bitstring") format,
- but support of binary labels has been completely removed per
- RFC 3363.
-
Many applications in <acronym>BIND</acronym> 9 do not understand
- the binary label format at all any more, and will return an
- error if given.
+ For IPv6 reverse lookups, <acronym>BIND</acronym> 9 supports
+ the traditional "nibble" format used in the
+ <emphasis>ip6.arpa</emphasis> domain, as well as the older, deprecated
+ <emphasis>ip6.int</emphasis> domain.
+ Older versions of <acronym>BIND</acronym> 9
+ supported the "binary label" (also known as "bitstring") format,
+ but support of binary labels has been completely removed per
+ RFC 3363.
+ Many applications in <acronym>BIND</acronym> 9 do not understand
+ the binary label format at all any more, and will return an
+ error if given.
In particular, an authoritative <acronym>BIND</acronym> 9
- name server will not load a zone file containing binary labels.
+ name server will not load a zone file containing binary labels.
</para>
<para>
- For an overview of the format and structure of IPv6 addresses,
- see <xref linkend="ipv6addresses"/>.
+ For an overview of the format and structure of IPv6 addresses,
+ see <xref linkend="ipv6addresses"/>.
</para>
<sect2>
- <title>Address Lookups Using AAAA Records</title>
+ <title>Address Lookups Using AAAA Records</title>
- The IPv6 AAAA record is a parallel to the IPv4 A record,
- and, unlike the deprecated A6 record, specifies the entire
- IPv6 address in a single record. For example,
- </para>
+ <para>
+ The IPv6 AAAA record is a parallel to the IPv4 A record,
+ and, unlike the deprecated A6 record, specifies the entire
+ IPv6 address in a single record. For example,
+ </para>
<programlisting>
$ORIGIN example.com.
host 3600 IN AAAA 2001:db8::1
</programlisting>
- Use of IPv4-in-IPv6 mapped addresses is not recommended.
+ <para>
+ Use of IPv4-in-IPv6 mapped addresses is not recommended.
If a host has an IPv4 address, use an A record, not
- a AAAA, with <literal>::ffff:192.168.42.1</literal> as
- the address.
- </para>
+ a AAAA, with <literal>::ffff:192.168.42.1</literal> as
+ the address.
+ </para>
</sect2>
<sect2>
- <title>Address to Name Lookups Using Nibble Format</title>
-
- When looking up an address in nibble format, the address
- components are simply reversed, just as in IPv4, and
- <literal>ip6.arpa.</literal> is appended to the
- resulting name.
- For example, the following would provide reverse name lookup for
- a host with address
- <literal>2001:db8::1</literal>.
- </para>
+ <title>Address to Name Lookups Using Nibble Format</title>
+
+ <para>
+ When looking up an address in nibble format, the address
+ components are simply reversed, just as in IPv4, and
+ <literal>ip6.arpa.</literal> is appended to the
+ resulting name.
+ For example, the following would provide reverse name lookup for
+ a host with address
+ <literal>2001:db8::1</literal>.
+ </para>
<programlisting>
$ORIGIN 0.0.0.0.0.0.0.0.8.b.d.0.1.0.0.2.ip6.arpa.
1.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0 14400 IN PTR (
- host.example.com. )
+ host.example.com. )
</programlisting>
</sect2>
<sect1>
<title>The Lightweight Resolver Library</title>
<para>
- Traditionally applications have been linked with a stub resolver
- library that sends recursive DNS queries to a local caching name
- server.
+ Traditionally applications have been linked with a stub resolver
+ library that sends recursive DNS queries to a local caching name
+ server.
</para>
<para>
- IPv6 once introduced new complexity into the resolution process,
- such as following A6 chains and DNAME records, and simultaneous
- lookup of IPv4 and IPv6 addresses. Though most of the complexity was
- then removed, these are hard or impossible
- to implement in a traditional stub resolver.
+ IPv6 once introduced new complexity into the resolution process,
+ such as following A6 chains and DNAME records, and simultaneous
+ lookup of IPv4 and IPv6 addresses. Though most of the complexity was
+ then removed, these are hard or impossible
+ to implement in a traditional stub resolver.
</para>
<para>
-
<acronym>BIND</acronym> 9 therefore can also provide resolution
- services to local clients
- using a combination of a lightweight resolver library and a resolver
- daemon process running on the local host. These communicate using
- a simple UDP-based protocol, the "lightweight resolver protocol"
- that is distinct from and simpler than the full DNS protocol.
+ <acronym>BIND</acronym> 9 therefore can also provide resolution
+ services to local clients
+ using a combination of a lightweight resolver library and a resolver
+ daemon process running on the local host. These communicate using
+ a simple UDP-based protocol, the "lightweight resolver protocol"
+ that is distinct from and simpler than the full DNS protocol.
</para>
</sect1>
<sect1 id="lwresd">
<title>Running a Resolver Daemon</title>
<para>
- To use the lightweight resolver interface, the system must
- run the resolver daemon <command>lwresd</command> or a
- local
- name server configured with a <command>lwres</command>
- statement.
+ To use the lightweight resolver interface, the system must
+ run the resolver daemon <command>lwresd</command> or a
+ local
+ name server configured with a <command>lwres</command>
+ statement.
</para>
<para>
- By default, applications using the lightweight resolver library will
- make
- UDP requests to the IPv4 loopback address (127.0.0.1) on port 921.
- The
- address can be overridden by <command>lwserver</command>
- lines in
- <filename>/etc/resolv.conf</filename>.
+ By default, applications using the lightweight resolver library will
+ make
+ UDP requests to the IPv4 loopback address (127.0.0.1) on port 921.
+ The
+ address can be overridden by <command>lwserver</command>
+ lines in
+ <filename>/etc/resolv.conf</filename>.
</para>
<para>
- The daemon currently only looks in the DNS, but in the future
- it may use other sources such as <filename>/etc/hosts</filename>,
- NIS, etc.
+ The daemon currently only looks in the DNS, but in the future
+ it may use other sources such as <filename>/etc/hosts</filename>,
+ NIS, etc.
</para>
<para>
- The <command>lwresd</command> daemon is essentially a
- caching-only name server that responds to requests using the
- lightweight
- resolver protocol rather than the DNS protocol. Because it needs
- to run on each host, it is designed to require no or minimal
- configuration.
- Unless configured otherwise, it uses the name servers listed on
- <command>nameserver</command> lines in <filename>/etc/resolv.conf</filename>
- as forwarders, but is also capable of doing the resolution
- autonomously if
- none are specified.
+ The <command>lwresd</command> daemon is essentially a
+ caching-only name server that responds to requests using the
+ lightweight
+ resolver protocol rather than the DNS protocol. Because it needs
+ to run on each host, it is designed to require no or minimal
+ configuration.
+ Unless configured otherwise, it uses the name servers listed on
+ <command>nameserver</command> lines in <filename>/etc/resolv.conf</filename>
+ as forwarders, but is also capable of doing the resolution
+ autonomously if
+ none are specified.
</para>
<para>
- The <command>lwresd</command> daemon may also be
- configured with a
- <filename>named.conf</filename> style configuration file,
- in
- <filename>/etc/lwresd.conf</filename> by default. A name
- server may also
- be configured to act as a lightweight resolver daemon using the
- <command>lwres</command> statement in <filename>named.conf</filename>.
+ The <command>lwresd</command> daemon may also be
+ configured with a
+ <filename>named.conf</filename> style configuration file,
+ in
+ <filename>/etc/lwresd.conf</filename> by default. A name
+ server may also
+ be configured to act as a lightweight resolver daemon using the
+ <command>lwres</command> statement in <filename>named.conf</filename>.
</para>
</sect1>
<sect1 id="configuration_file_elements">
<title>Configuration File Elements</title>
<para>
-
Following is a list of elements used throughout the <acronym>BIND</acronym> configuration
- file documentation:
+ Following is a list of elements used throughout the <acronym>BIND</acronym> configuration
+ file documentation:
</para>
<informaltable colsep="0" rowsep="0">
- <tgroup cols="2" colsep="0" rowsep="0" tgroupstyle="2Level-table">
- <colspec colname="1" colnum="1" colsep="0" colwidth="1.855in"/>
- <colspec colname="2" colnum="2" colsep="0" colwidth="3.770in"/>
- <tbody>
- <row rowsep="0">
- <entry colname="1">
- <varname>acl_name</varname>
- </para>
- </entry>
- <entry colname="2">
- The name of an <varname>address_match_list</varname> as
- defined by the <command>acl</command> statement.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <varname>address_match_list</varname>
- </para>
- </entry>
- <entry colname="2">
- A list of one or more
- <varname>ip_addr</varname>,
- <varname>ip_prefix</varname>, <varname>key_id</varname>,
- or <varname>acl_name</varname> elements, see
- <xref linkend="address_match_lists"/>.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <varname>masters_list</varname>
- </para>
- </entry>
- <entry colname="2">
- A named list of one or more <varname>ip_addr</varname>
+ <tgroup cols="2" colsep="0" rowsep="0" tgroupstyle="2Level-table">
+ <colspec colname="1" colnum="1" colsep="0" colwidth="1.855in"/>
+ <colspec colname="2" colnum="2" colsep="0" colwidth="3.770in"/>
+ <tbody>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ <varname>acl_name</varname>
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ The name of an <varname>address_match_list</varname> as
+ defined by the <command>acl</command> statement.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ <varname>address_match_list</varname>
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ A list of one or more
+ <varname>ip_addr</varname>,
+ <varname>ip_prefix</varname>, <varname>key_id</varname>,
+ or <varname>acl_name</varname> elements, see
+ <xref linkend="address_match_lists"/>.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ <varname>masters_list</varname>
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ A named list of one or more <varname>ip_addr</varname>
with optional <varname>key_id</varname> and/or
<varname>ip_port</varname>.
A <varname>masters_list</varname> may include other
<varname>masters_lists</varname>.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <varname>domain_name</varname>
- </para>
- </entry>
- <entry colname="2">
- A quoted string which will be used as
- a DNS name, for example "<literal>my.test.domain</literal>".
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <varname>namelist</varname>
- </para>
- </entry>
- <entry colname="2">
- A list of one or more <varname>domain_name</varname>
- elements.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <varname>dotted_decimal</varname>
- </para>
- </entry>
- <entry colname="2">
- One to four integers valued 0 through
- 255 separated by dots (`.'), such as <command>123</command>,
- <command>45.67</command> or <command>89.123.45.67</command>.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <varname>ip4_addr</varname>
- </para>
- </entry>
- <entry colname="2">
- An IPv4 address with exactly four elements
- in <varname>dotted_decimal</varname> notation.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <varname>ip6_addr</varname>
- </para>
- </entry>
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ <varname>domain_name</varname>
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ A quoted string which will be used as
+ a DNS name, for example "<literal>my.test.domain</literal>".
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ <varname>namelist</varname>
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ A list of one or more <varname>domain_name</varname>
+ elements.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ <varname>dotted_decimal</varname>
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ One to four integers valued 0 through
+ 255 separated by dots (`.'), such as <command>123</command>,
+ <command>45.67</command> or <command>89.123.45.67</command>.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ <varname>ip4_addr</varname>
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ An IPv4 address with exactly four elements
+ in <varname>dotted_decimal</varname> notation.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ <varname>ip6_addr</varname>
+ </para>
+ </entry>
<entry colname="2">
<para>
An IPv6 address, such as <command>2001:db8::1234</command>.
</para>
</entry>
</row>
- <row rowsep="0">
- <entry colname="1">
- <varname>ip_addr</varname>
- </para>
- </entry>
- <entry colname="2">
- An <varname>ip4_addr</varname> or <varname>ip6_addr</varname>.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <varname>ip_dscp</varname>
- </para>
- </entry>
- <entry colname="2">
- A <varname>number</varname> between 0 and 63, used
- to select a differentiated services code point (DSCP)
- value for use with outgoing traffic on operating systems
- that support DSCP.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <varname>ip_port</varname>
- </para>
- </entry>
- <entry colname="2">
- An IP port <varname>number</varname>.
- The <varname>number</varname> is limited to 0
- through 65535, with values
- below 1024 typically restricted to use by processes running
- as root.
- In some cases, an asterisk (`*') character can be used as a
- placeholder to
- select a random high-numbered port.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <varname>ip_prefix</varname>
- </para>
- </entry>
- <entry colname="2">
- An IP network specified as an <varname>ip_addr</varname>,
- followed by a slash (`/') and then the number of bits in the
- netmask.
- Trailing zeros in a <varname>ip_addr</varname>
- may omitted.
- For example, <command>127/8</command> is the
- network <command>127.0.0.0</command> with
- netmask <command>255.0.0.0</command> and <command>1.2.3.0/28</command> is
- network <command>1.2.3.0</command> with netmask <command>255.255.255.240</command>.
- </para>
- When specifying a prefix involving a IPv6 scoped address
- the scope may be omitted. In that case the prefix will
- match packets from any scope.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <varname>key_id</varname>
- </para>
- </entry>
- <entry colname="2">
- A <varname>domain_name</varname> representing
- the name of a shared key, to be used for transaction
- security.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <varname>key_list</varname>
- </para>
- </entry>
- <entry colname="2">
- A list of one or more
- <varname>key_id</varname>s,
- separated by semicolons and ending with a semicolon.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <varname>number</varname>
- </para>
- </entry>
- <entry colname="2">
- A non-negative 32-bit integer
- (i.e., a number between 0 and 4294967295, inclusive).
- Its acceptable value might further
- be limited by the context in which it is used.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <varname>path_name</varname>
- </para>
- </entry>
- <entry colname="2">
- A quoted string which will be used as
- a pathname, such as <filename>zones/master/my.test.domain</filename>.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <varname>port_list</varname>
- </para>
- </entry>
- <entry colname="2">
- A list of an <varname>ip_port</varname> or a port
- range.
- A port range is specified in the form of
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ <varname>ip_addr</varname>
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ An <varname>ip4_addr</varname> or <varname>ip6_addr</varname>.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ <varname>ip_dscp</varname>
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ A <varname>number</varname> between 0 and 63, used
+ to select a differentiated services code point (DSCP)
+ value for use with outgoing traffic on operating systems
+ that support DSCP.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ <varname>ip_port</varname>
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ An IP port <varname>number</varname>.
+ The <varname>number</varname> is limited to 0
+ through 65535, with values
+ below 1024 typically restricted to use by processes running
+ as root.
+ In some cases, an asterisk (`*') character can be used as a
+ placeholder to
+ select a random high-numbered port.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ <varname>ip_prefix</varname>
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ An IP network specified as an <varname>ip_addr</varname>,
+ followed by a slash (`/') and then the number of bits in the
+ netmask.
+ Trailing zeros in a <varname>ip_addr</varname>
+ may omitted.
+ For example, <command>127/8</command> is the
+ network <command>127.0.0.0</command> with
+ netmask <command>255.0.0.0</command> and <command>1.2.3.0/28</command> is
+ network <command>1.2.3.0</command> with netmask <command>255.255.255.240</command>.
+ </para>
+ <para>
+ When specifying a prefix involving a IPv6 scoped address
+ the scope may be omitted. In that case the prefix will
+ match packets from any scope.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ <varname>key_id</varname>
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ A <varname>domain_name</varname> representing
+ the name of a shared key, to be used for transaction
+ security.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ <varname>key_list</varname>
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ A list of one or more
+ <varname>key_id</varname>s,
+ separated by semicolons and ending with a semicolon.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ <varname>number</varname>
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ A non-negative 32-bit integer
+ (i.e., a number between 0 and 4294967295, inclusive).
+ Its acceptable value might further
+ be limited by the context in which it is used.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ <varname>path_name</varname>
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ A quoted string which will be used as
+ a pathname, such as <filename>zones/master/my.test.domain</filename>.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ <varname>port_list</varname>
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ A list of an <varname>ip_port</varname> or a port
+ range.
+ A port range is specified in the form of
<userinput>range</userinput> followed by
two <varname>ip_port</varname>s,
<varname>port_low</varname> and
ports from 1024 through 65535.
In either case an asterisk (`*') character is not
allowed as a valid <varname>ip_port</varname>.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <varname>size_spec</varname>
- </para>
- </entry>
- <entry colname="2">
- A 64-bit unsigned integer, or the keywords
- <userinput>unlimited</userinput> or
- <userinput>default</userinput>.
- </para>
- Integers may take values
- 0 <= value <= 18446744073709551615, though
- certain parameters
- (such as <command>max-journal-size</command>) may
- use a more limited range within these extremes.
- In most cases, setting a value to 0 does not
- literally mean zero; it means "undefined" or
- "as big as possible", depending on the context.
- See the expalantions of particular parameters
- that use <varname>size_spec</varname>
- for details on how they interpret its use.
- </para>
- Numeric values can optionally be followed by a
- scaling factor:
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ <varname>size_spec</varname>
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ A 64-bit unsigned integer, or the keywords
+ <userinput>unlimited</userinput> or
+ <userinput>default</userinput>.
+ </para>
+ <para>
+ Integers may take values
+ 0 <= value <= 18446744073709551615, though
+ certain parameters
+ (such as <command>max-journal-size</command>) may
+ use a more limited range within these extremes.
+ In most cases, setting a value to 0 does not
+ literally mean zero; it means "undefined" or
+ "as big as possible", depending on the context.
+ See the expalantions of particular parameters
+ that use <varname>size_spec</varname>
+ for details on how they interpret its use.
+ </para>
+ <para>
+ Numeric values can optionally be followed by a
+ scaling factor:
<userinput>K</userinput> or <userinput>k</userinput>
for kilobytes,
<userinput>M</userinput> or <userinput>m</userinput>
for megabytes, and
- <userinput>G</userinput> or <userinput>g</userinput>
- for gigabytes, which scale by 1024, 1024*1024, and
- 1024*1024*1024 respectively.
- </para>
- <para>
- <varname>unlimited</varname> generally means
- "as big as possible", and is usually the best
- way to safely set a very large number.
- </para>
- <para>
- <varname>default</varname>
- uses the limit that was in force when the server was started.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <varname>yes_or_no</varname>
- </para>
- </entry>
- <entry colname="2">
- Either <userinput>yes</userinput> or <userinput>no</userinput>.
- The words <userinput>true</userinput> and <userinput>false</userinput> are
- also accepted, as are the numbers <userinput>1</userinput>
- and <userinput>0</userinput>.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <varname>dialup_option</varname>
- </para>
- </entry>
- <entry colname="2">
- One of <userinput>yes</userinput>,
- <userinput>no</userinput>, <userinput>notify</userinput>,
- <userinput>notify-passive</userinput>, <userinput>refresh</userinput> or
- <userinput>passive</userinput>.
- When used in a zone, <userinput>notify-passive</userinput>,
- <userinput>refresh</userinput>, and <userinput>passive</userinput>
- are restricted to slave and stub zones.
- </para>
- </entry>
- </row>
- </tbody>
- </tgroup>
+ <userinput>G</userinput> or <userinput>g</userinput>
+ for gigabytes, which scale by 1024, 1024*1024, and
+ 1024*1024*1024 respectively.
+ </para>
+ <para>
+ <varname>unlimited</varname> generally means
+ "as big as possible", and is usually the best
+ way to safely set a very large number.
+ </para>
+ <para>
+ <varname>default</varname>
+ uses the limit that was in force when the server was started.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ <varname>yes_or_no</varname>
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ Either <userinput>yes</userinput> or <userinput>no</userinput>.
+ The words <userinput>true</userinput> and <userinput>false</userinput> are
+ also accepted, as are the numbers <userinput>1</userinput>
+ and <userinput>0</userinput>.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ <varname>dialup_option</varname>
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ One of <userinput>yes</userinput>,
+ <userinput>no</userinput>, <userinput>notify</userinput>,
+ <userinput>notify-passive</userinput>, <userinput>refresh</userinput> or
+ <userinput>passive</userinput>.
+ When used in a zone, <userinput>notify-passive</userinput>,
+ <userinput>refresh</userinput>, and <userinput>passive</userinput>
+ are restricted to slave and stub zones.
+ </para>
+ </entry>
+ </row>
+ </tbody>
+ </tgroup>
</informaltable>
<sect2 id="address_match_lists">
- <title>Address Match Lists</title>
- <sect3>
- <title>Syntax</title>
+ <title>Address Match Lists</title>
+ <sect3>
+ <title>Syntax</title>
<programlisting><varname>address_match_list</varname> = address_match_list_element ;
<optional> address_match_list_element; ... </optional>
key key_id | acl_name | { address_match_list } )
</programlisting>
- </sect3>
- <sect3>
- <title>Definition and Usage</title>
- Address match lists are primarily used to determine access
- control for various server operations. They are also used in
- the <command>listen-on</command> and <command>sortlist</command>
- statements. The elements which constitute an address match
- list can be any of the following:
- </para>
- <itemizedlist>
- <listitem>
- <simpara>an IP address (IPv4 or IPv6)</simpara>
- </listitem>
- <listitem>
- <simpara>an IP prefix (in `/' notation)</simpara>
- </listitem>
- <listitem>
- <simpara>
- a key ID, as defined by the <command>key</command>
- statement
- </simpara>
- </listitem>
- <listitem>
- <simpara>the name of an address match list defined with
- the <command>acl</command> statement
- </simpara>
- </listitem>
- <listitem>
- <simpara>a nested address match list enclosed in braces</simpara>
- </listitem>
- </itemizedlist>
-
- Elements can be negated with a leading exclamation mark (`!'),
- and the match list names "any", "none", "localhost", and
- "localnets" are predefined. More information on those names
- can be found in the description of the acl statement.
- </para>
-
- The addition of the key clause made the name of this syntactic
- element something of a misnomer, since security keys can be used
- to validate access without regard to a host or network address.
- Nonetheless, the term "address match list" is still used
- throughout the documentation.
- </para>
-
- When a given IP address or prefix is compared to an address
- match list, the comparison takes place in approximately O(1)
- time. However, key comparisons require that the list of keys
- be traversed until a matching key is found, and therefore may
- be somewhat slower.
- </para>
-
- The interpretation of a match depends on whether the list is being
- used for access control, defining <command>listen-on</command> ports, or in a
- <command>sortlist</command>, and whether the element was negated.
- </para>
+ </sect3>
+ <sect3>
+ <title>Definition and Usage</title>
+ <para>
+ Address match lists are primarily used to determine access
+ control for various server operations. They are also used in
+ the <command>listen-on</command> and <command>sortlist</command>
+ statements. The elements which constitute an address match
+ list can be any of the following:
+ </para>
+ <itemizedlist>
+ <listitem>
+ <simpara>an IP address (IPv4 or IPv6)</simpara>
+ </listitem>
+ <listitem>
+ <simpara>an IP prefix (in `/' notation)</simpara>
+ </listitem>
+ <listitem>
+ <simpara>
+ a key ID, as defined by the <command>key</command>
+ statement
+ </simpara>
+ </listitem>
+ <listitem>
+ <simpara>the name of an address match list defined with
+ the <command>acl</command> statement
+ </simpara>
+ </listitem>
+ <listitem>
+ <simpara>a nested address match list enclosed in braces</simpara>
+ </listitem>
+ </itemizedlist>
+
+ <para>
+ Elements can be negated with a leading exclamation mark (`!'),
+ and the match list names "any", "none", "localhost", and
+ "localnets" are predefined. More information on those names
+ can be found in the description of the acl statement.
+ </para>
+
+ <para>
+ The addition of the key clause made the name of this syntactic
+ element something of a misnomer, since security keys can be used
+ to validate access without regard to a host or network address.
+ Nonetheless, the term "address match list" is still used
+ throughout the documentation.
+ </para>
+
+ <para>
+ When a given IP address or prefix is compared to an address
+ match list, the comparison takes place in approximately O(1)
+ time. However, key comparisons require that the list of keys
+ be traversed until a matching key is found, and therefore may
+ be somewhat slower.
+ </para>
+
+ <para>
+ The interpretation of a match depends on whether the list is being
+ used for access control, defining <command>listen-on</command> ports, or in a
+ <command>sortlist</command>, and whether the element was negated.
+ </para>
<para>
When used as an access control list, a non-negated match
addresses which do not match the list.
</para>
- Order of insertion is significant. If more than one element
- in an ACL is found to match a given IP address or prefix,
- preference will be given to the one that came
- <emphasis>first</emphasis> in the ACL definition.
- Because of this first-match behavior, an element that
- defines a subset of another element in the list should
- come before the broader element, regardless of whether
- either is negated. For example, in
- <command>1.2.3/24; ! 1.2.3.13;</command>
- the 1.2.3.13 element is completely useless because the
- algorithm will match any lookup for 1.2.3.13 to the 1.2.3/24
- element. Using <command>! 1.2.3.13; 1.2.3/24</command> fixes
- that problem by having 1.2.3.13 blocked by the negation, but
- all other 1.2.3.* hosts fall through.
- </para>
- </sect3>
+ <para>
+ Order of insertion is significant. If more than one element
+ in an ACL is found to match a given IP address or prefix,
+ preference will be given to the one that came
+ <emphasis>first</emphasis> in the ACL definition.
+ Because of this first-match behavior, an element that
+ defines a subset of another element in the list should
+ come before the broader element, regardless of whether
+ either is negated. For example, in
+ <command>1.2.3/24; ! 1.2.3.13;</command>
+ the 1.2.3.13 element is completely useless because the
+ algorithm will match any lookup for 1.2.3.13 to the 1.2.3/24
+ element. Using <command>! 1.2.3.13; 1.2.3/24</command> fixes
+ that problem by having 1.2.3.13 blocked by the negation, but
+ all other 1.2.3.* hosts fall through.
+ </para>
+ </sect3>
</sect2>
<sect2>
- <title>Comment Syntax</title>
-
-
The <acronym>BIND</acronym> 9 comment syntax allows for
- comments to appear
-
anywhere that whitespace may appear in a <acronym>BIND</acronym> configuration
- file. To appeal to programmers of all kinds, they can be written
- in the C, C++, or shell/perl style.
- </para>
-
- <sect3>
- <title>Syntax</title>
-
-
<programlisting>/* This is a <acronym>BIND</acronym> comment as in C */</programlisting>
-
<programlisting>// This is a <acronym>BIND</acronym> comment as in C++</programlisting>
-
<programlisting># This is a <acronym>BIND</acronym> comment as in common UNIX shells
+ <title>Comment Syntax</title>
+
+ <para>
+ The <acronym>BIND</acronym> 9 comment syntax allows for
+ comments to appear
+ anywhere that whitespace may appear in a <acronym>BIND</acronym> configuration
+ file. To appeal to programmers of all kinds, they can be written
+ in the C, C++, or shell/perl style.
+ </para>
+
+ <sect3>
+ <title>Syntax</title>
+
+ <para>
+ <programlisting>/* This is a <acronym>BIND</acronym> comment as in C */</programlisting>
+ <programlisting>// This is a <acronym>BIND</acronym> comment as in C++</programlisting>
+ <programlisting># This is a <acronym>BIND</acronym> comment as in common UNIX shells
# and perl</programlisting>
- </para>
- </sect3>
- <sect3>
- <title>Definition and Usage</title>
- Comments may appear anywhere that whitespace may appear in
-
a <acronym>BIND</acronym> configuration file.
- </para>
- C-style comments start with the two characters /* (slash,
- star) and end with */ (star, slash). Because they are completely
- delimited with these characters, they can be used to comment only
- a portion of a line or to span multiple lines.
- </para>
- C-style comments cannot be nested. For example, the following
- is not valid because the entire comment ends with the first */:
- </para>
+ </para>
+ </sect3>
+ <sect3>
+ <title>Definition and Usage</title>
+ <para>
+ Comments may appear anywhere that whitespace may appear in
+ a <acronym>BIND</acronym> configuration file.
+ </para>
+ <para>
+ C-style comments start with the two characters /* (slash,
+ star) and end with */ (star, slash). Because they are completely
+ delimited with these characters, they can be used to comment only
+ a portion of a line or to span multiple lines.
+ </para>
+ <para>
+ C-style comments cannot be nested. For example, the following
+ is not valid because the entire comment ends with the first */:
+ </para>
+ <para>
<programlisting>/* This is the start of a comment.
This is still part of the comment.
This is no longer in any comment. */
</programlisting>
- </para>
+ </para>
- C++-style comments start with the two characters // (slash,
- slash) and continue to the end of the physical line. They cannot
- be continued across multiple physical lines; to have one logical
- comment span multiple lines, each line must use the // pair.
- For example:
- </para>
+ <para>
+ C++-style comments start with the two characters // (slash,
+ slash) and continue to the end of the physical line. They cannot
+ be continued across multiple physical lines; to have one logical
+ comment span multiple lines, each line must use the // pair.
+ For example:
+ </para>
+ <para>
<programlisting>// This is the start of a comment. The next line
// is a new comment, even though it is logically
// part of the previous comment.
</programlisting>
- </para>
- Shell-style (or perl-style, if you prefer) comments start
- with the character <literal>#</literal> (number sign)
- and continue to the end of the
- physical line, as in C++ comments.
- For example:
- </para>
+ </para>
+ <para>
+ Shell-style (or perl-style, if you prefer) comments start
+ with the character <literal>#</literal> (number sign)
+ and continue to the end of the
+ physical line, as in C++ comments.
+ For example:
+ </para>
+ <para>
<programlisting># This is the start of a comment. The next line
# is a new comment, even though it is logically
# part of the previous comment.
</programlisting>
- </para>
-
- <warning>
- You cannot use the semicolon (`;') character
- to start a comment such as you would in a zone file. The
- semicolon indicates the end of a configuration
- statement.
- </para>
- </warning>
- </sect3>
+ </para>
+
+ <warning>
+ <para>
+ You cannot use the semicolon (`;') character
+ to start a comment such as you would in a zone file. The
+ semicolon indicates the end of a configuration
+ statement.
+ </para>
+ </warning>
+ </sect3>
</sect2>
</sect1>
<title>Configuration File Grammar</title>
<para>
-
A <acronym>BIND</acronym> 9 configuration consists of
- statements and comments.
- Statements end with a semicolon. Statements and comments are the
- only elements that can appear without enclosing braces. Many
- statements contain a block of sub-statements, which are also
- terminated with a semicolon.
+ A <acronym>BIND</acronym> 9 configuration consists of
+ statements and comments.
+ Statements end with a semicolon. Statements and comments are the
+ only elements that can appear without enclosing braces. Many
+ statements contain a block of sub-statements, which are also
+ terminated with a semicolon.
</para>
<para>
- The following statements are supported:
+ The following statements are supported:
</para>
<informaltable colsep="0" rowsep="0">
- <tgroup cols="2" colsep="0" rowsep="0" tgroupstyle="2Level-table">
- <colspec colname="1" colnum="1" colsep="0" colwidth="1.336in"/>
- <colspec colname="2" colnum="2" colsep="0" colwidth="3.778in"/>
- <tbody>
- <row rowsep="0">
- <entry colname="1">
-
<para><command>acl</command></para>
- </entry>
- <entry colname="2">
- defines a named IP address
- matching list, for access control and other uses.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
-
<para><command>controls</command></para>
- </entry>
- <entry colname="2">
- declares control channels to be used
- by the <command>rndc</command> utility.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
-
<para><command>include</command></para>
- </entry>
- <entry colname="2">
- includes a file.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
-
<para><command>key</command></para>
- </entry>
- <entry colname="2">
- specifies key information for use in
- authentication and authorization using TSIG.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
-
<para><command>logging</command></para>
- </entry>
- <entry colname="2">
- specifies what the server logs, and where
- the log messages are sent.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
-
<para><command>lwres</command></para>
- </entry>
- <entry colname="2">
- configures <command>named</command> to
- also act as a light-weight resolver daemon (<command>lwresd</command>).
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
-
<para><command>masters</command></para>
- </entry>
- <entry colname="2">
- defines a named masters list for
- inclusion in stub and slave zones'
- <command>masters</command> or
- <command>also-notify</command> lists.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
-
<para><command>options</command></para>
- </entry>
- <entry colname="2">
- controls global server configuration
- options and sets defaults for other statements.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
-
<para><command>server</command></para>
- </entry>
- <entry colname="2">
- sets certain configuration options on
- a per-server basis.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
-
<para><command>statistics-channels</command></para>
- </entry>
- <entry colname="2">
+ <tgroup cols="2" colsep="0" rowsep="0" tgroupstyle="2Level-table">
+ <colspec colname="1" colnum="1" colsep="0" colwidth="1.336in"/>
+ <colspec colname="2" colnum="2" colsep="0" colwidth="3.778in"/>
+ <tbody>
+ <row rowsep="0">
+ <entry colname="1">
+ <para><command>acl</command></para>
+ </entry>
+ <entry colname="2">
+ <para>
+ defines a named IP address
+ matching list, for access control and other uses.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para><command>controls</command></para>
+ </entry>
+ <entry colname="2">
+ <para>
+ declares control channels to be used
+ by the <command>rndc</command> utility.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para><command>include</command></para>
+ </entry>
+ <entry colname="2">
+ <para>
+ includes a file.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para><command>key</command></para>
+ </entry>
+ <entry colname="2">
+ <para>
+ specifies key information for use in
+ authentication and authorization using TSIG.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para><command>logging</command></para>
+ </entry>
+ <entry colname="2">
+ <para>
+ specifies what the server logs, and where
+ the log messages are sent.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para><command>lwres</command></para>
+ </entry>
+ <entry colname="2">
+ <para>
+ configures <command>named</command> to
+ also act as a light-weight resolver daemon (<command>lwresd</command>).
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para><command>masters</command></para>
+ </entry>
+ <entry colname="2">
+ <para>
+ defines a named masters list for
+ inclusion in stub and slave zones'
+ <command>masters</command> or
+ <command>also-notify</command> lists.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para><command>options</command></para>
+ </entry>
+ <entry colname="2">
+ <para>
+ controls global server configuration
+ options and sets defaults for other statements.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para><command>server</command></para>
+ </entry>
+ <entry colname="2">
+ <para>
+ sets certain configuration options on
+ a per-server basis.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para><command>statistics-channels</command></para>
+ </entry>
+ <entry colname="2">
+ <para>
declares communication channels to get access to
<command>named</command> statistics.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
-
<para><command>trusted-keys</command></para>
- </entry>
- <entry colname="2">
- defines trusted DNSSEC keys.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
-
<para><command>managed-keys</command></para>
- </entry>
- <entry colname="2">
- lists DNSSEC keys to be kept up to date
- using RFC 5011 trust anchor maintenance.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
-
<para><command>view</command></para>
- </entry>
- <entry colname="2">
- defines a view.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
-
<para><command>zone</command></para>
- </entry>
- <entry colname="2">
- defines a zone.
- </para>
- </entry>
- </row>
- </tbody>
- </tgroup>
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para><command>trusted-keys</command></para>
+ </entry>
+ <entry colname="2">
+ <para>
+ defines trusted DNSSEC keys.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para><command>managed-keys</command></para>
+ </entry>
+ <entry colname="2">
+ <para>
+ lists DNSSEC keys to be kept up to date
+ using RFC 5011 trust anchor maintenance.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para><command>view</command></para>
+ </entry>
+ <entry colname="2">
+ <para>
+ defines a view.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para><command>zone</command></para>
+ </entry>
+ <entry colname="2">
+ <para>
+ defines a zone.
+ </para>
+ </entry>
+ </row>
+ </tbody>
+ </tgroup>
</informaltable>
<para>
- The <command>logging</command> and
- <command>options</command> statements may only occur once
- per
- configuration.
+ The <command>logging</command> and
+ <command>options</command> statements may only occur once
+ per
+ configuration.
</para>
<sect2>
- <title><command>acl</command> Statement Grammar</title>
+ <title><command>acl</command> Statement Grammar</title>
<programlisting><command>acl</command> acl-name {
address_match_list
</sect2>
<sect2 id="acl">
- <title><command>acl</command> Statement Definition and
- Usage</title>
-
- The <command>acl</command> statement assigns a symbolic
- name to an address match list. It gets its name from a primary
- use of address match lists: Access Control Lists (ACLs).
- </para>
-
- Note that an address match list's name must be defined
- with <command>acl</command> before it can be used
- elsewhere; no forward references are allowed.
- </para>
-
- The following ACLs are built-in:
- </para>
-
- <informaltable colsep="0" rowsep="0">
- <tgroup cols="2" colsep="0" rowsep="0" tgroupstyle="3Level-table">
- <colspec colname="1" colnum="1" colsep="0" colwidth="1.130in"/>
- <colspec colname="2" colnum="2" colsep="0" colwidth="4.000in"/>
- <tbody>
- <row rowsep="0">
- <entry colname="1">
-
<para><command>any</command></para>
- </entry>
- <entry colname="2">
- Matches all hosts.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
-
<para><command>none</command></para>
- </entry>
- <entry colname="2">
- Matches no hosts.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
-
<para><command>localhost</command></para>
- </entry>
- <entry colname="2">
- Matches the IPv4 and IPv6 addresses of all network
- interfaces on the system.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
-
<para><command>localnets</command></para>
- </entry>
- <entry colname="2">
- Matches any host on an IPv4 or IPv6 network
- for which the system has an interface.
- Some systems do not provide a way to determine the prefix
- lengths of
- local IPv6 addresses.
- In such a case, <command>localnets</command>
- only matches the local
- IPv6 addresses, just like <command>localhost</command>.
- </para>
- </entry>
- </row>
- </tbody>
- </tgroup>
- </informaltable>
-
-
When <acronym>BIND</acronym> 9 is built with GeoIP support,
- ACLs can also be used for geographic access restrictions.
- This is done by specifying an ACL element of the form:
- <command>geoip <optional>db <replaceable>database</replaceable></optional> <replaceable>field</replaceable> <replaceable>value</replaceable></command>
- </para>
- The <replaceable>field</replaceable> indicates which field
- to search for a match. Available fields are "country",
- "region", "city", "continent", "postal" (postal code),
- "metro" (metro code), "area" (area code), "tz" (timezone),
- "isp", "org", "asnum", "domain" and "netspeed".
- </para>
- <replaceable>value</replaceable> is the value to searched for
- within the database. A string may be quoted if it contains
- spaces or other special characters. If this is a "country"
- search and the string is two characters long, then it must be a
- standard ISO-3166-1 two-letter country code, and if it is three
- characters long then it must be an ISO-3166-1 three-letter
- country code; otherwise it is the full name of the country.
- Similarly, if this is a "region" search and the string is
- two characters long, then it must be a standard two-letter state
- or province abbreviation; otherwise it is the full name of the
- state or province.
- </para>
- The <replaceable>database</replaceable> field indicates which
- GeoIP database to search for a match. In most cases this is
- unnecessary, because most search fields can only be found in
- a single database. However, searches for country can be
- answered from the "city", "region", or "country" databases,
- and searches for region (i.e., state or province) can be
- answered from the "city" or "region" databases. For these
- search types, specifying a <replaceable>database</replaceable>
- will force the query to be answered from that database and no
- other. If <replaceable>database</replaceable> is not
- specified, then these queries will be answered from the "city",
- database if it is installed, or the "region" database if it is
- installed, or the "country" database, in that order.
- </para>
- Some example GeoIP ACLs:
- </para>
-
<programlisting>geoip country US;
+ <title><command>acl</command> Statement Definition and
+ Usage</title>
+
+ <para>
+ The <command>acl</command> statement assigns a symbolic
+ name to an address match list. It gets its name from a primary
+ use of address match lists: Access Control Lists (ACLs).
+ </para>
+
+ <para>
+ Note that an address match list's name must be defined
+ with <command>acl</command> before it can be used
+ elsewhere; no forward references are allowed.
+ </para>
+
+ <para>
+ The following ACLs are built-in:
+ </para>
+
+ <informaltable colsep="0" rowsep="0">
+ <tgroup cols="2" colsep="0" rowsep="0" tgroupstyle="3Level-table">
+ <colspec colname="1" colnum="1" colsep="0" colwidth="1.130in"/>
+ <colspec colname="2" colnum="2" colsep="0" colwidth="4.000in"/>
+ <tbody>
+ <row rowsep="0">
+ <entry colname="1">
+ <para><command>any</command></para>
+ </entry>
+ <entry colname="2">
+ <para>
+ Matches all hosts.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para><command>none</command></para>
+ </entry>
+ <entry colname="2">
+ <para>
+ Matches no hosts.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para><command>localhost</command></para>
+ </entry>
+ <entry colname="2">
+ <para>
+ Matches the IPv4 and IPv6 addresses of all network
+ interfaces on the system.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para><command>localnets</command></para>
+ </entry>
+ <entry colname="2">
+ <para>
+ Matches any host on an IPv4 or IPv6 network
+ for which the system has an interface.
+ Some systems do not provide a way to determine the prefix
+ lengths of
+ local IPv6 addresses.
+ In such a case, <command>localnets</command>
+ only matches the local
+ IPv6 addresses, just like <command>localhost</command>.
+ </para>
+ </entry>
+ </row>
+ </tbody>
+ </tgroup>
+ </informaltable>
+
+ <para>
+ When <acronym>BIND</acronym> 9 is built with GeoIP support,
+ ACLs can also be used for geographic access restrictions.
+ This is done by specifying an ACL element of the form:
+ <command>geoip <optional>db <replaceable>database</replaceable></optional> <replaceable>field</replaceable> <replaceable>value</replaceable></command>
+ </para>
+ <para>
+ The <replaceable>field</replaceable> indicates which field
+ to search for a match. Available fields are "country",
+ "region", "city", "continent", "postal" (postal code),
+ "metro" (metro code), "area" (area code), "tz" (timezone),
+ "isp", "org", "asnum", "domain" and "netspeed".
+ </para>
+ <para>
+ <replaceable>value</replaceable> is the value to searched for
+ within the database. A string may be quoted if it contains
+ spaces or other special characters. If this is a "country"
+ search and the string is two characters long, then it must be a
+ standard ISO-3166-1 two-letter country code, and if it is three
+ characters long then it must be an ISO-3166-1 three-letter
+ country code; otherwise it is the full name of the country.
+ Similarly, if this is a "region" search and the string is
+ two characters long, then it must be a standard two-letter state
+ or province abbreviation; otherwise it is the full name of the
+ state or province.
+ </para>
+ <para>
+ The <replaceable>database</replaceable> field indicates which
+ GeoIP database to search for a match. In most cases this is
+ unnecessary, because most search fields can only be found in
+ a single database. However, searches for country can be
+ answered from the "city", "region", or "country" databases,
+ and searches for region (i.e., state or province) can be
+ answered from the "city" or "region" databases. For these
+ search types, specifying a <replaceable>database</replaceable>
+ will force the query to be answered from that database and no
+ other. If <replaceable>database</replaceable> is not
+ specified, then these queries will be answered from the "city",
+ database if it is installed, or the "region" database if it is
+ installed, or the "country" database, in that order.
+ </para>
+ <para>
+ Some example GeoIP ACLs:
+ </para>
+ <programlisting>geoip country US;
geoip country JAP;
geoip db country country Canada;
geoip db region region WA;
</sect2>
<sect2>
- <title><command>controls</command> Statement Grammar</title>
+ <title><command>controls</command> Statement Grammar</title>
<programlisting><command>controls</command> {
[ inet ( ip_addr | * ) [ port ip_port ]
- allow { <replaceable> address_match_list </replaceable> }
- keys { <replaceable>key_list</replaceable> }; ]
+ allow { <replaceable> address_match_list </replaceable> }
+ keys { <replaceable>key_list</replaceable> }; ]
[ inet ...; ]
[ unix <replaceable>path</replaceable> perm <replaceable>number</replaceable> owner <replaceable>number</replaceable> group <replaceable>number</replaceable>
keys { <replaceable>key_list</replaceable> }; ]
</sect2>
<sect2 id="controls_statement_definition_and_usage">
- <title><command>controls</command> Statement Definition and
- Usage</title>
-
- The <command>controls</command> statement declares control
- channels to be used by system administrators to control the
- operation of the name server. These control channels are
- used by the <command>rndc</command> utility to send
- commands to and retrieve non-DNS results from a name server.
- </para>
-
- An <command>inet</command> control channel is a TCP socket
+ <title><command>controls</command> Statement Definition and
+ Usage</title>
+
+ <para>
+ The <command>controls</command> statement declares control
+ channels to be used by system administrators to control the
+ operation of the name server. These control channels are
+ used by the <command>rndc</command> utility to send
+ commands to and retrieve non-DNS results from a name server.
+ </para>
+
+ <para>
+ An <command>inet</command> control channel is a TCP socket
listening at the specified <command>ip_port</command> on the
specified <command>ip_addr</command>, which can be an IPv4 or IPv6
address. An <command>ip_addr</command> of <literal>*</literal> (asterisk) is
interpreted as the IPv4 wildcard address; connections will be
accepted on any of the system's IPv4 addresses.
To listen on the IPv6 wildcard address,
- use an <command>ip_addr</command> of <literal>::</literal>.
- If you will only use <command>rndc</command> on the local host,
- using the loopback address (<literal>127.0.0.1</literal>
- or <literal>::1</literal>) is recommended for maximum security.
- </para>
-
- If no port is specified, port 953 is used. The asterisk
+ use an <command>ip_addr</command> of <literal>::</literal>.
+ If you will only use <command>rndc</command> on the local host,
+ using the loopback address (<literal>127.0.0.1</literal>
+ or <literal>::1</literal>) is recommended for maximum security.
+ </para>
+
+ <para>
+ If no port is specified, port 953 is used. The asterisk
"<literal>*</literal>" cannot be used for <command>ip_port</command>.
- </para>
+ </para>
- The ability to issue commands over the control channel is
- restricted by the <command>allow</command> and
- <command>keys</command> clauses.
+ <para>
+ The ability to issue commands over the control channel is
+ restricted by the <command>allow</command> and
+ <command>keys</command> clauses.
Connections to the control channel are permitted based on the
- <command>address_match_list</command>. This is for simple
- IP address based filtering only; any <command>key_id</command>
- elements of the <command>address_match_list</command>
- are ignored.
- </para>
+ <command>address_match_list</command>. This is for simple
+ IP address based filtering only; any <command>key_id</command>
+ elements of the <command>address_match_list</command>
+ are ignored.
+ </para>
<para>
A <command>unix</command> control channel is a UNIX domain
as the permissions on the socket itself are ignored.
</para>
- The primary authorization mechanism of the command
- channel is the <command>key_list</command>, which
- contains a list of <command>key_id</command>s.
- Each <command>key_id</command> in the <command>key_list</command>
+ <para>
+ The primary authorization mechanism of the command
+ channel is the <command>key_list</command>, which
+ contains a list of <command>key_id</command>s.
+ Each <command>key_id</command> in the <command>key_list</command>
is authorized to execute commands over the control channel.
- See <xref linkend="rndc"/> in <xref linkend="admin_tools"/>)
+ See <xref linkend="rndc"/> in <xref linkend="admin_tools"/>)
for information about configuring keys in <command>rndc</command>.
- </para>
-
- If no <command>controls</command> statement is present,
- <command>named</command> will set up a default
- control channel listening on the loopback address 127.0.0.1
- and its IPv6 counterpart ::1.
- In this case, and also when the <command>controls</command> statement
- is present but does not have a <command>keys</command> clause,
- <command>named</command> will attempt to load the command channel key
- from the file <filename>rndc.key</filename> in
- <filename>/etc</filename> (or whatever <varname>sysconfdir</varname>
-
was specified as when <acronym>BIND</acronym> was built).
- To create a <filename>rndc.key</filename> file, run
- <userinput>rndc-confgen -a</userinput>.
- </para>
-
- The <filename>rndc.key</filename> feature was created to
-
ease the transition of systems from <acronym>BIND</acronym> 8,
- which did not have digital signatures on its command channel
- messages and thus did not have a <command>keys</command> clause.
-
-
It makes it possible to use an existing <acronym>BIND</acronym> 8
-
configuration file in <acronym>BIND</acronym> 9 unchanged,
- and still have <command>rndc</command> work the same way
- <command>ndc</command> worked in BIND 8, simply by executing the
- command <userinput>rndc-confgen -a</userinput> after BIND 9 is
- installed.
- </para>
-
- Since the <filename>rndc.key</filename> feature
- is only intended to allow the backward-compatible usage of
-
<acronym>BIND</acronym> 8 configuration files, this
- feature does not
- have a high degree of configurability. You cannot easily change
- the key name or the size of the secret, so you should make a
- <filename>rndc.conf</filename> with your own key if you
- wish to change
- those things. The <filename>rndc.key</filename> file
- also has its
- permissions set such that only the owner of the file (the user that
- <command>named</command> is running as) can access it.
- If you
- desire greater flexibility in allowing other users to access
- <command>rndc</command> commands, then you need to create
- a
- <filename>rndc.conf</filename> file and make it group
- readable by a group
- that contains the users who should have access.
- </para>
-
- To disable the command channel, use an empty
+ </para>
+
+ <para>
+ If no <command>controls</command> statement is present,
+ <command>named</command> will set up a default
+ control channel listening on the loopback address 127.0.0.1
+ and its IPv6 counterpart ::1.
+ In this case, and also when the <command>controls</command> statement
+ is present but does not have a <command>keys</command> clause,
+ <command>named</command> will attempt to load the command channel key
+ from the file <filename>rndc.key</filename> in
+ <filename>/etc</filename> (or whatever <varname>sysconfdir</varname>
+ was specified as when <acronym>BIND</acronym> was built).
+ To create a <filename>rndc.key</filename> file, run
+ <userinput>rndc-confgen -a</userinput>.
+ </para>
+
+ <para>
+ The <filename>rndc.key</filename> feature was created to
+ ease the transition of systems from <acronym>BIND</acronym> 8,
+ which did not have digital signatures on its command channel
+ messages and thus did not have a <command>keys</command> clause.
+
+ It makes it possible to use an existing <acronym>BIND</acronym> 8
+ configuration file in <acronym>BIND</acronym> 9 unchanged,
+ and still have <command>rndc</command> work the same way
+ <command>ndc</command> worked in BIND 8, simply by executing the
+ command <userinput>rndc-confgen -a</userinput> after BIND 9 is
+ installed.
+ </para>
+
+ <para>
+ Since the <filename>rndc.key</filename> feature
+ is only intended to allow the backward-compatible usage of
+ <acronym>BIND</acronym> 8 configuration files, this
+ feature does not
+ have a high degree of configurability. You cannot easily change
+ the key name or the size of the secret, so you should make a
+ <filename>rndc.conf</filename> with your own key if you
+ wish to change
+ those things. The <filename>rndc.key</filename> file
+ also has its
+ permissions set such that only the owner of the file (the user that
+ <command>named</command> is running as) can access it.
+ If you
+ desire greater flexibility in allowing other users to access
+ <command>rndc</command> commands, then you need to create
+ a
+ <filename>rndc.conf</filename> file and make it group
+ readable by a group
+ that contains the users who should have access.
+ </para>
+
+ <para>
+ To disable the command channel, use an empty
<command>controls</command> statement:
<command>controls { };</command>.
- </para>
+ </para>
</sect2>
<sect2>
- <title><command>include</command> Statement Grammar</title>
-
<programlisting><command>include</command> <replaceable>filename</replaceable>;</programlisting>
+ <title><command>include</command> Statement Grammar</title>
+ <programlisting><command>include</command> <replaceable>filename</replaceable>;</programlisting>
</sect2>
<sect2>
- <title><command>include</command> Statement Definition and
- Usage</title>
-
- The <command>include</command> statement inserts the
- specified file at the point where the <command>include</command>
- statement is encountered. The <command>include</command>
- statement facilitates the administration of configuration
- files
- by permitting the reading or writing of some things but not
- others. For example, the statement could include private keys
- that are readable only by the name server.
- </para>
+ <title><command>include</command> Statement Definition and
+ Usage</title>
+
+ <para>
+ The <command>include</command> statement inserts the
+ specified file at the point where the <command>include</command>
+ statement is encountered. The <command>include</command>
+ statement facilitates the administration of configuration
+ files
+ by permitting the reading or writing of some things but not
+ others. For example, the statement could include private keys
+ that are readable only by the name server.
+ </para>
</sect2>
<sect2>
- <title><command>key</command> Statement Grammar</title>
+ <title><command>key</command> Statement Grammar</title>
<programlisting><command>key</command> <replaceable>key_id</replaceable> {
algorithm <replaceable>string</replaceable>;
</sect2>
<sect2>
- <title><command>key</command> Statement Definition and Usage</title>
-
- The <command>key</command> statement defines a shared
- secret key for use with TSIG (see <xref linkend="tsig"/>)
- or the command channel
- (see <xref linkend="controls_statement_definition_and_usage"/>).
- </para>
-
- The <command>key</command> statement can occur at the
- top level
- of the configuration file or inside a <command>view</command>
- statement. Keys defined in top-level <command>key</command>
- statements can be used in all views. Keys intended for use in
- a <command>controls</command> statement
- (see <xref linkend="controls_statement_definition_and_usage"/>)
- must be defined at the top level.
- </para>
-
- The <replaceable>key_id</replaceable>, also known as the
- key name, is a domain name uniquely identifying the key. It can
- be used in a <command>server</command>
- statement to cause requests sent to that
- server to be signed with this key, or in address match lists to
- verify that incoming requests have been signed with a key
- matching this name, algorithm, and secret.
- </para>
+ <title><command>key</command> Statement Definition and Usage</title>
+
+ <para>
+ The <command>key</command> statement defines a shared
+ secret key for use with TSIG (see <xref linkend="tsig"/>)
+ or the command channel
+ (see <xref linkend="controls_statement_definition_and_usage"/>).
+ </para>
+
+ <para>
+ The <command>key</command> statement can occur at the
+ top level
+ of the configuration file or inside a <command>view</command>
+ statement. Keys defined in top-level <command>key</command>
+ statements can be used in all views. Keys intended for use in
+ a <command>controls</command> statement
+ (see <xref linkend="controls_statement_definition_and_usage"/>)
+ must be defined at the top level.
+ </para>
+
+ <para>
+ The <replaceable>key_id</replaceable>, also known as the
+ key name, is a domain name uniquely identifying the key. It can
+ be used in a <command>server</command>
+ statement to cause requests sent to that
+ server to be signed with this key, or in address match lists to
+ verify that incoming requests have been signed with a key
+ matching this name, algorithm, and secret.
+ </para>
<para>
The <replaceable>algorithm_id</replaceable> is a string
</sect2>
<sect2>
- <title><command>logging</command> Statement Grammar</title>
+ <title><command>logging</command> Statement Grammar</title>
<programlisting><command>logging</command> {
[ <command>channel</command> <replaceable>channel_name</replaceable> {
( <command>file</command> <replaceable>path_name</replaceable>
- [ <command>versions</command> ( <replaceable>number</replaceable> | <command>unlimited</command> ) ]
- [ <command>size</command> <replaceable>size_spec</replaceable> ]
+ [ <command>versions</command> ( <replaceable>number</replaceable> | <command>unlimited</command> ) ]
+ [ <command>size</command> <replaceable>size_spec</replaceable> ]
| <command>syslog</command> <replaceable>syslog_facility</replaceable>
| <command>stderr</command>
| <command>null</command> );
[ <command>severity</command> (<option>critical</option> | <option>error</option> | <option>warning</option> | <option>notice</option> |
- <option>info</option> | <option>debug</option> [ <replaceable>level</replaceable> ] | <option>dynamic</option> ); ]
+ <option>info</option> | <option>debug</option> [ <replaceable>level</replaceable> ] | <option>dynamic</option> ); ]
[ <command>print-category</command> <option>yes</option> or <option>no</option>; ]
[ <command>print-severity</command> <option>yes</option> or <option>no</option>; ]
[ <command>print-time</command> <option>yes</option> or <option>no</option>; ]
</sect2>
<sect2>
- <title><command>logging</command> Statement Definition and
- Usage</title>
-
- The <command>logging</command> statement configures a
- wide
- variety of logging options for the name server. Its <command>channel</command> phrase
- associates output methods, format options and severity levels with
- a name that can then be used with the <command>category</command> phrase
- to select how various classes of messages are logged.
- </para>
- Only one <command>logging</command> statement is used to
- define
- as many channels and categories as are wanted. If there is no <command>logging</command> statement,
- the logging configuration will be:
- </para>
+ <title><command>logging</command> Statement Definition and
+ Usage</title>
+
+ <para>
+ The <command>logging</command> statement configures a
+ wide
+ variety of logging options for the name server. Its <command>channel</command> phrase
+ associates output methods, format options and severity levels with
+ a name that can then be used with the <command>category</command> phrase
+ to select how various classes of messages are logged.
+ </para>
+ <para>
+ Only one <command>logging</command> statement is used to
+ define
+ as many channels and categories as are wanted. If there is no <command>logging</command> statement,
+ the logging configuration will be:
+ </para>
<programlisting>logging {
category default { default_syslog; default_debug; };
};
</programlisting>
-
In <acronym>BIND</acronym> 9, the logging configuration
- is only established when
-
the entire configuration file has been parsed. In <acronym>BIND</acronym> 8, it was
- established as soon as the <command>logging</command>
- statement
- was parsed. When the server is starting up, all logging messages
- regarding syntax errors in the configuration file go to the default
- channels, or to standard error if the "<option>-g</option>" option
- was specified.
- </para>
-
- <sect3>
- <title>The <command>channel</command> Phrase</title>
-
- All log output goes to one or more <emphasis>channels</emphasis>;
- you can make as many of them as you want.
- </para>
-
- Every channel definition must include a destination clause that
- says whether messages selected for the channel go to a file, to a
- particular syslog facility, to the standard error stream, or are
- discarded. It can optionally also limit the message severity level
- that will be accepted by the channel (the default is
- <command>info</command>), and whether to include a
- <command>named</command>-generated time stamp, the
- category name
- and/or severity level (the default is not to include any).
- </para>
-
- The <command>null</command> destination clause
- causes all messages sent to the channel to be discarded;
- in that case, other options for the channel are meaningless.
- </para>
-
- The <command>file</command> destination clause directs
- the channel
- to a disk file. It can include limitations
- both on how large the file is allowed to become, and how many
- versions
- of the file will be saved each time the file is opened.
- </para>
-
- If you use the <command>versions</command> log file
- option, then
- <command>named</command> will retain that many backup
- versions of the file by
- renaming them when opening. For example, if you choose to keep
- three old versions
- of the file <filename>lamers.log</filename>, then just
- before it is opened
- <filename>lamers.log.1</filename> is renamed to
- <filename>lamers.log.2</filename>, <filename>lamers.log.0</filename> is renamed
- to <filename>lamers.log.1</filename>, and <filename>lamers.log</filename> is
- renamed to <filename>lamers.log.0</filename>.
- You can say <command>versions unlimited</command> to
- not limit
- the number of versions.
- If a <command>size</command> option is associated with
- the log file,
- then renaming is only done when the file being opened exceeds the
- indicated size. No backup versions are kept by default; any
- existing
- log file is simply appended.
- </para>
-
- The <command>size</command> option for files is used
- to limit log
- growth. If the file ever exceeds the size, then <command>named</command> will
- stop writing to the file unless it has a <command>versions</command> option
- associated with it. If backup versions are kept, the files are
- rolled as
- described above and a new one begun. If there is no
- <command>versions</command> option, no more data will
- be written to the log
- until some out-of-band mechanism removes or truncates the log to
- less than the
- maximum size. The default behavior is not to limit the size of
- the
- file.
- </para>
-
- Example usage of the <command>size</command> and
- <command>versions</command> options:
- </para>
+ <para>
+ In <acronym>BIND</acronym> 9, the logging configuration
+ is only established when
+ the entire configuration file has been parsed. In <acronym>BIND</acronym> 8, it was
+ established as soon as the <command>logging</command>
+ statement
+ was parsed. When the server is starting up, all logging messages
+ regarding syntax errors in the configuration file go to the default
+ channels, or to standard error if the "<option>-g</option>" option
+ was specified.
+ </para>
+
+ <sect3>
+ <title>The <command>channel</command> Phrase</title>
+
+ <para>
+ All log output goes to one or more <emphasis>channels</emphasis>;
+ you can make as many of them as you want.
+ </para>
+
+ <para>
+ Every channel definition must include a destination clause that
+ says whether messages selected for the channel go to a file, to a
+ particular syslog facility, to the standard error stream, or are
+ discarded. It can optionally also limit the message severity level
+ that will be accepted by the channel (the default is
+ <command>info</command>), and whether to include a
+ <command>named</command>-generated time stamp, the
+ category name
+ and/or severity level (the default is not to include any).
+ </para>
+
+ <para>
+ The <command>null</command> destination clause
+ causes all messages sent to the channel to be discarded;
+ in that case, other options for the channel are meaningless.
+ </para>
+
+ <para>
+ The <command>file</command> destination clause directs
+ the channel
+ to a disk file. It can include limitations
+ both on how large the file is allowed to become, and how many
+ versions
+ of the file will be saved each time the file is opened.
+ </para>
+
+ <para>
+ If you use the <command>versions</command> log file
+ option, then
+ <command>named</command> will retain that many backup
+ versions of the file by
+ renaming them when opening. For example, if you choose to keep
+ three old versions
+ of the file <filename>lamers.log</filename>, then just
+ before it is opened
+ <filename>lamers.log.1</filename> is renamed to
+ <filename>lamers.log.2</filename>, <filename>lamers.log.0</filename> is renamed
+ to <filename>lamers.log.1</filename>, and <filename>lamers.log</filename> is
+ renamed to <filename>lamers.log.0</filename>.
+ You can say <command>versions unlimited</command> to
+ not limit
+ the number of versions.
+ If a <command>size</command> option is associated with
+ the log file,
+ then renaming is only done when the file being opened exceeds the
+ indicated size. No backup versions are kept by default; any
+ existing
+ log file is simply appended.
+ </para>
+
+ <para>
+ The <command>size</command> option for files is used
+ to limit log
+ growth. If the file ever exceeds the size, then <command>named</command> will
+ stop writing to the file unless it has a <command>versions</command> option
+ associated with it. If backup versions are kept, the files are
+ rolled as
+ described above and a new one begun. If there is no
+ <command>versions</command> option, no more data will
+ be written to the log
+ until some out-of-band mechanism removes or truncates the log to
+ less than the
+ maximum size. The default behavior is not to limit the size of
+ the
+ file.
+ </para>
+
+ <para>
+ Example usage of the <command>size</command> and
+ <command>versions</command> options:
+ </para>
<programlisting>channel an_example_channel {
file "example.log" versions 3 size 20m;
};
</programlisting>
- The <command>syslog</command> destination clause
- directs the
- channel to the system log. Its argument is a
- syslog facility as described in the <command>syslog</command> man
- page. Known facilities are <command>kern</command>, <command>user</command>,
- <command>mail</command>, <command>daemon</command>, <command>auth</command>,
- <command>syslog</command>, <command>lpr</command>, <command>news</command>,
- <command>uucp</command>, <command>cron</command>, <command>authpriv</command>,
- <command>ftp</command>, <command>local0</command>, <command>local1</command>,
- <command>local2</command>, <command>local3</command>, <command>local4</command>,
- <command>local5</command>, <command>local6</command> and
- <command>local7</command>, however not all facilities
- are supported on
- all operating systems.
- How <command>syslog</command> will handle messages
- sent to
- this facility is described in the <command>syslog.conf</command> man
- page. If you have a system which uses a very old version of <command>syslog</command> that
- only uses two arguments to the <command>openlog()</command> function,
- then this clause is silently ignored.
- </para>
+ <para>
+ The <command>syslog</command> destination clause
+ directs the
+ channel to the system log. Its argument is a
+ syslog facility as described in the <command>syslog</command> man
+ page. Known facilities are <command>kern</command>, <command>user</command>,
+ <command>mail</command>, <command>daemon</command>, <command>auth</command>,
+ <command>syslog</command>, <command>lpr</command>, <command>news</command>,
+ <command>uucp</command>, <command>cron</command>, <command>authpriv</command>,
+ <command>ftp</command>, <command>local0</command>, <command>local1</command>,
+ <command>local2</command>, <command>local3</command>, <command>local4</command>,
+ <command>local5</command>, <command>local6</command> and
+ <command>local7</command>, however not all facilities
+ are supported on
+ all operating systems.
+ How <command>syslog</command> will handle messages
+ sent to
+ this facility is described in the <command>syslog.conf</command> man
+ page. If you have a system which uses a very old version of <command>syslog</command> that
+ only uses two arguments to the <command>openlog()</command> function,
+ then this clause is silently ignored.
+ </para>
+ <para>
On Windows machines syslog messages are directed to the EventViewer.
- </para>
- The <command>severity</command> clause works like <command>syslog</command>'s
- "priorities", except that they can also be used if you are writing
- straight to a file rather than using <command>syslog</command>.
- Messages which are not at least of the severity level given will
- not be selected for the channel; messages of higher severity
- levels
- will be accepted.
- </para>
- If you are using <command>syslog</command>, then the <command>syslog.conf</command> priorities
- will also determine what eventually passes through. For example,
- defining a channel facility and severity as <command>daemon</command> and <command>debug</command> but
- only logging <command>daemon.warning</command> via <command>syslog.conf</command> will
- cause messages of severity <command>info</command> and
- <command>notice</command> to
- be dropped. If the situation were reversed, with <command>named</command> writing
- messages of only <command>warning</command> or higher,
- then <command>syslogd</command> would
- print all messages it received from the channel.
- </para>
-
- The <command>stderr</command> destination clause
- directs the
- channel to the server's standard error stream. This is intended
- for
- use when the server is running as a foreground process, for
- example
- when debugging a configuration.
- </para>
-
- The server can supply extensive debugging information when
- it is in debugging mode. If the server's global debug level is
- greater
- than zero, then debugging mode will be active. The global debug
- level is set either by starting the <command>named</command> server
- with the <option>-d</option> flag followed by a positive integer,
- or by running <command>rndc trace</command>.
- The global debug level
- can be set to zero, and debugging mode turned off, by running <command>rndc
+ </para>
+ <para>
+ The <command>severity</command> clause works like <command>syslog</command>'s
+ "priorities", except that they can also be used if you are writing
+ straight to a file rather than using <command>syslog</command>.
+ Messages which are not at least of the severity level given will
+ not be selected for the channel; messages of higher severity
+ levels
+ will be accepted.
+ </para>
+ <para>
+ If you are using <command>syslog</command>, then the <command>syslog.conf</command> priorities
+ will also determine what eventually passes through. For example,
+ defining a channel facility and severity as <command>daemon</command> and <command>debug</command> but
+ only logging <command>daemon.warning</command> via <command>syslog.conf</command> will
+ cause messages of severity <command>info</command> and
+ <command>notice</command> to
+ be dropped. If the situation were reversed, with <command>named</command> writing
+ messages of only <command>warning</command> or higher,
+ then <command>syslogd</command> would
+ print all messages it received from the channel.
+ </para>
+
+ <para>
+ The <command>stderr</command> destination clause
+ directs the
+ channel to the server's standard error stream. This is intended
+ for
+ use when the server is running as a foreground process, for
+ example
+ when debugging a configuration.
+ </para>
+
+ <para>
+ The server can supply extensive debugging information when
+ it is in debugging mode. If the server's global debug level is
+ greater
+ than zero, then debugging mode will be active. The global debug
+ level is set either by starting the <command>named</command> server
+ with the <option>-d</option> flag followed by a positive integer,
+ or by running <command>rndc trace</command>.
+ The global debug level
+ can be set to zero, and debugging mode turned off, by running <command>rndc
notrace</command>. All debugging messages in the server have a debug
- level, and higher debug levels give more detailed output. Channels
- that specify a specific debug severity, for example:
- </para>
+ level, and higher debug levels give more detailed output. Channels
+ that specify a specific debug severity, for example:
+ </para>
<programlisting>channel specific_debug_level {
file "foo";
};
</programlisting>
- will get debugging output of level 3 or less any time the
- server is in debugging mode, regardless of the global debugging
- level. Channels with <command>dynamic</command>
- severity use the
- server's global debug level to determine what messages to print.
- </para>
- If <command>print-time</command> has been turned on,
- then
- the date and time will be logged. <command>print-time</command> may
- be specified for a <command>syslog</command> channel,
- but is usually
- pointless since <command>syslog</command> also logs
- the date and
- time. If <command>print-category</command> is
- requested, then the
- category of the message will be logged as well. Finally, if <command>print-severity</command> is
- on, then the severity level of the message will be logged. The <command>print-</command> options may
- be used in any combination, and will always be printed in the
- following
- order: time, category, severity. Here is an example where all
- three <command>print-</command> options
- are on:
- </para>
-
- <computeroutput>28-Feb-2000 15:05:32.863 general: notice: running</computeroutput>
- </para>
-
- There are four predefined channels that are used for
- <command>named</command>'s default logging as follows.
- How they are
- used is described in <xref linkend="the_category_phrase"/>.
- </para>
+ <para>
+ will get debugging output of level 3 or less any time the
+ server is in debugging mode, regardless of the global debugging
+ level. Channels with <command>dynamic</command>
+ severity use the
+ server's global debug level to determine what messages to print.
+ </para>
+ <para>
+ If <command>print-time</command> has been turned on,
+ then
+ the date and time will be logged. <command>print-time</command> may
+ be specified for a <command>syslog</command> channel,
+ but is usually
+ pointless since <command>syslog</command> also logs
+ the date and
+ time. If <command>print-category</command> is
+ requested, then the
+ category of the message will be logged as well. Finally, if <command>print-severity</command> is
+ on, then the severity level of the message will be logged. The <command>print-</command> options may
+ be used in any combination, and will always be printed in the
+ following
+ order: time, category, severity. Here is an example where all
+ three <command>print-</command> options
+ are on:
+ </para>
+
+ <para>
+ <computeroutput>28-Feb-2000 15:05:32.863 general: notice: running</computeroutput>
+ </para>
+
+ <para>
+ There are four predefined channels that are used for
+ <command>named</command>'s default logging as follows.
+ How they are
+ used is described in <xref linkend="the_category_phrase"/>.
+ </para>
<programlisting>channel default_syslog {
// send to syslog's daemon facility
};
</programlisting>
- The <command>default_debug</command> channel has the
- special
- property that it only produces output when the server's debug
- level is
- nonzero. It normally writes to a file called <filename>named.run</filename>
- in the server's working directory.
- </para>
-
- For security reasons, when the "<option>-u</option>"
- command line option is used, the <filename>named.run</filename> file
- is created only after <command>named</command> has
- changed to the
- new UID, and any debug output generated while <command>named</command> is
- starting up and still running as root is discarded. If you need
- to capture this output, you must run the server with the "<option>-g</option>"
- option and redirect standard error to a file.
- </para>
-
- Once a channel is defined, it cannot be redefined. Thus you
- cannot alter the built-in channels directly, but you can modify
- the default logging by pointing categories at channels you have
- defined.
- </para>
- </sect3>
-
- <sect3 id="the_category_phrase">
- <title>The <command>category</command> Phrase</title>
-
- There are many categories, so you can send the logs you want
- to see wherever you want, without seeing logs you don't want. If
- you don't specify a list of channels for a category, then log
- messages
- in that category will be sent to the <command>default</command> category
- instead. If you don't specify a default category, the following
- "default default" is used:
- </para>
+ <para>
+ The <command>default_debug</command> channel has the
+ special
+ property that it only produces output when the server's debug
+ level is
+ nonzero. It normally writes to a file called <filename>named.run</filename>
+ in the server's working directory.
+ </para>
+
+ <para>
+ For security reasons, when the "<option>-u</option>"
+ command line option is used, the <filename>named.run</filename> file
+ is created only after <command>named</command> has
+ changed to the
+ new UID, and any debug output generated while <command>named</command> is
+ starting up and still running as root is discarded. If you need
+ to capture this output, you must run the server with the "<option>-g</option>"
+ option and redirect standard error to a file.
+ </para>
+
+ <para>
+ Once a channel is defined, it cannot be redefined. Thus you
+ cannot alter the built-in channels directly, but you can modify
+ the default logging by pointing categories at channels you have
+ defined.
+ </para>
+ </sect3>
+
+ <sect3 id="the_category_phrase">
+ <title>The <command>category</command> Phrase</title>
+
+ <para>
+ There are many categories, so you can send the logs you want
+ to see wherever you want, without seeing logs you don't want. If
+ you don't specify a list of channels for a category, then log
+ messages
+ in that category will be sent to the <command>default</command> category
+ instead. If you don't specify a default category, the following
+ "default default" is used:
+ </para>
<programlisting>category default { default_syslog; default_debug; };
</programlisting>
- As an example, let's say you want to log security events to
- a file, but you also want keep the default logging behavior. You'd
- specify the following:
- </para>
+ <para>
+ As an example, let's say you want to log security events to
+ a file, but you also want keep the default logging behavior. You'd
+ specify the following:
+ </para>
<programlisting>channel my_security_channel {
file "my_security_file";
default_debug;
};</programlisting>
- To discard all messages in a category, specify the <command>null</command> channel:
- </para>
+ <para>
+ To discard all messages in a category, specify the <command>null</command> channel:
+ </para>
<programlisting>category xfer-out { null; };
category notify { null; };
</programlisting>
- <para>
- Following are the available categories and brief descriptions
- of the types of log information they contain. More
- categories may be added in future <acronym>BIND</acronym> releases.
- </para>
- <informaltable colsep="0" rowsep="0">
- <tgroup cols="2" colsep="0" rowsep="0" tgroupstyle="4Level-table">
- <colspec colname="1" colnum="1" colsep="0" colwidth="1.150in"/>
- <colspec colname="2" colnum="2" colsep="0" colwidth="3.350in"/>
- <tbody>
- <row rowsep="0">
- <entry colname="1">
- <para><command>default</command></para>
- </entry>
- <entry colname="2">
- <para>
- The default category defines the logging
- options for those categories where no specific
- configuration has been
- defined.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para><command>general</command></para>
- </entry>
- <entry colname="2">
- <para>
- The catch-all. Many things still aren't
- classified into categories, and they all end up here.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para><command>database</command></para>
- </entry>
- <entry colname="2">
- <para>
- Messages relating to the databases used
- internally by the name server to store zone and cache
- data.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para><command>security</command></para>
- </entry>
- <entry colname="2">
- <para>
- Approval and denial of requests.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para><command>config</command></para>
- </entry>
- <entry colname="2">
- <para>
- Configuration file parsing and processing.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para><command>resolver</command></para>
- </entry>
- <entry colname="2">
- <para>
- DNS resolution, such as the recursive
- lookups performed on behalf of clients by a caching name
- server.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para><command>xfer-in</command></para>
- </entry>
- <entry colname="2">
- <para>
- Zone transfers the server is receiving.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para><command>xfer-out</command></para>
- </entry>
- <entry colname="2">
- <para>
- Zone transfers the server is sending.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para><command>notify</command></para>
- </entry>
- <entry colname="2">
- <para>
- The NOTIFY protocol.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para><command>client</command></para>
- </entry>
- <entry colname="2">
- <para>
- Processing of client requests.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para><command>unmatched</command></para>
- </entry>
- <entry colname="2">
- <para>
- Messages that <command>named</command> was unable to determine the
- class of or for which there was no matching <command>view</command>.
- A one line summary is also logged to the <command>client</command> category.
- This category is best sent to a file or stderr, by
- default it is sent to
- the <command>null</command> channel.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para><command>network</command></para>
- </entry>
- <entry colname="2">
- <para>
- Network operations.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para><command>update</command></para>
- </entry>
- <entry colname="2">
- <para>
- Dynamic updates.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para><command>update-security</command></para>
- </entry>
- <entry colname="2">
- <para>
- Approval and denial of update requests.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para><command>queries</command></para>
- </entry>
- <entry colname="2">
- <para>
- Specify where queries should be logged to.
- </para>
- <para>
- At startup, specifying the category <command>queries</command> will also
- enable query logging unless <command>querylog</command> option has been
- specified.
- </para>
-
+ <para>
+ Following are the available categories and brief descriptions
+ of the types of log information they contain. More
+ categories may be added in future <acronym>BIND</acronym> releases.
+ </para>
+ <informaltable colsep="0" rowsep="0">
+ <tgroup cols="2" colsep="0" rowsep="0" tgroupstyle="4Level-table">
+ <colspec colname="1" colnum="1" colsep="0" colwidth="1.150in"/>
+ <colspec colname="2" colnum="2" colsep="0" colwidth="3.350in"/>
+ <tbody>
+ <row rowsep="0">
+ <entry colname="1">
+ <para><command>default</command></para>
+ </entry>
+ <entry colname="2">
<para>
- The query log entry reports the client's IP
- address and port number, and the query name,
- class and type. Next it reports whether the
- Recursion Desired flag was set (+ if set, -
- if not set), if the query was signed (S),
- EDNS was in use (E), if TCP was used (T), if
- DO (DNSSEC Ok) was set (D), or if CD (Checking
- Disabled) was set (C). After this the
- destination address the query was sent to is
- reported.
+ The default category defines the logging
+ options for those categories where no specific
+ configuration has been
+ defined.
</para>
-
- <para>
- <computeroutput>client 127.0.0.1#62536 (www.example.com): query: www.example.com IN AAAA +SE</computeroutput>
- </para>
- <para>
- <computeroutput>client ::1#62537 (www.example.net): query: www.example.net IN AAAA -SE</computeroutput>
- </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para><command>general</command></para>
+ </entry>
+ <entry colname="2">
<para>
- (The first part of this log message, showing the
- client address/port number and query name, is
- repeated in all subsequent log messages related
- to the same query.)
+ The catch-all. Many things still aren't
+ classified into categories, and they all end up here.
</para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para><command>query-errors</command></para>
- </entry>
- <entry colname="2">
- <para>
- Information about queries that resulted in some
- failure.
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para><command>database</command></para>
+ </entry>
+ <entry colname="2">
+ <para>
+ Messages relating to the databases used
+ internally by the name server to store zone and cache
+ data.
</para>
</entry>
</row>
- <row rowsep="0">
- <entry colname="1">
- <para><command>dispatch</command></para>
- </entry>
- <entry colname="2">
- <para>
- Dispatching of incoming packets to the
- server modules where they are to be processed.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para><command>dnssec</command></para>
- </entry>
- <entry colname="2">
- <para>
- DNSSEC and TSIG protocol processing.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para><command>lame-servers</command></para>
- </entry>
- <entry colname="2">
- <para>
- Lame servers. These are misconfigurations
- in remote servers, discovered by BIND 9 when trying to
- query those servers during resolution.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para><command>delegation-only</command></para>
- </entry>
+ <row rowsep="0">
+ <entry colname="1">
+ <para><command>security</command></para>
+ </entry>
<entry colname="2">
<para>
- Delegation only. Logs queries that have been
- forced to NXDOMAIN as the result of a
- delegation-only zone or a
- <command>delegation-only</command> in a hint
- or stub zone declaration.
+ Approval and denial of requests.
</para>
</entry>
</row>
- <row rowsep="0">
- <entry colname="1">
- <para><command>edns-disabled</command></para>
- </entry>
+ <row rowsep="0">
+ <entry colname="1">
+ <para><command>config</command></para>
+ </entry>
<entry colname="2">
<para>
- Log queries that have been forced to use plain
- DNS due to timeouts. This is often due to
- the remote servers not being RFC 1034 compliant
- (not always returning FORMERR or similar to
- EDNS queries and other extensions to the DNS
- when they are not understood). In other words, this is
- targeted at servers that fail to respond to
- DNS queries that they don't understand.
+ Configuration file parsing and processing.
</para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para><command>resolver</command></para>
+ </entry>
+ <entry colname="2">
<para>
- Note: the log message can also be due to
- packet loss. Before reporting servers for
- non-RFC 1034 compliance they should be re-tested
- to determine the nature of the non-compliance.
- This testing should prevent or reduce the
- number of false-positive reports.
+ DNS resolution, such as the recursive
+ lookups performed on behalf of clients by a caching name
+ server.
</para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para><command>xfer-in</command></para>
+ </entry>
+ <entry colname="2">
<para>
- Note: eventually <command>named</command> will have to stop
- treating such timeouts as due to RFC 1034 non
- compliance and start treating it as plain
- packet loss. Falsely classifying packet
- loss as due to RFC 1034 non compliance impacts
- on DNSSEC validation which requires EDNS for
- the DNSSEC records to be returned.
+ Zone transfers the server is receiving.
</para>
</entry>
</row>
- <row rowsep="0">
- <entry colname="1">
- <para><command>RPZ</command></para>
- </entry>
+ <row rowsep="0">
+ <entry colname="1">
+ <para><command>xfer-out</command></para>
+ </entry>
<entry colname="2">
<para>
- Information about errors in response policy zone files,
- rewritten responses, and at the highest
- <command>debug</command> levels, mere rewriting
- attempts.
+ Zone transfers the server is sending.
</para>
</entry>
</row>
- <row rowsep="0">
- <entry colname="1">
- <para><command>rate-limit</command></para>
- </entry>
+ <row rowsep="0">
+ <entry colname="1">
+ <para><command>notify</command></para>
+ </entry>
<entry colname="2">
<para>
- The start, periodic, and final notices of the
- rate limiting of a stream of responses are logged at
- <command>info</command> severity in this category.
- These messages include a hash value of the domain name
- of the response and the name itself,
- except when there is insufficient memory to record
- the name for the final notice
- The final notice is normally delayed until about one
- minute after rate limit stops.
- A lack of memory can hurry the final notice,
- in which case it starts with an asterisk (*).
- Various internal events are logged at debug 1 level
- and higher.
+ The NOTIFY protocol.
</para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para><command>client</command></para>
+ </entry>
+ <entry colname="2">
<para>
- Rate limiting of individual requests
- is logged in the <command>query-errors</command> category.
+ Processing of client requests.
</para>
</entry>
</row>
- </tbody>
- </tgroup>
- </informaltable>
- </sect3>
- <sect3>
- <title>The <command>query-errors</command> Category</title>
- <para>
- The <command>query-errors</command> category is
- specifically intended for debugging purposes: To identify
- why and how specific queries result in responses which
- indicate an error.
- Messages of this category are therefore only logged
- with <command>debug</command> levels.
- </para>
-
- <para>
- At the debug levels of 1 or higher, each response with the
- rcode of SERVFAIL is logged as follows:
- </para>
- <para>
- <computeroutput>client 127.0.0.1#61502: query failed (SERVFAIL) for www.example.com/IN/AAAA at query.c:3880</computeroutput>
- </para>
+ <row rowsep="0">
+ <entry colname="1">
+ <para><command>unmatched</command></para>
+ </entry>
+ <entry colname="2">
+ <para>
+ Messages that <command>named</command> was unable to determine the
+ class of or for which there was no matching <command>view</command>.
+ A one line summary is also logged to the <command>client</command> category.
+ This category is best sent to a file or stderr, by
+ default it is sent to
+ the <command>null</command> channel.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para><command>network</command></para>
+ </entry>
+ <entry colname="2">
+ <para>
+ Network operations.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para><command>update</command></para>
+ </entry>
+ <entry colname="2">
+ <para>
+ Dynamic updates.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para><command>update-security</command></para>
+ </entry>
+ <entry colname="2">
+ <para>
+ Approval and denial of update requests.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para><command>queries</command></para>
+ </entry>
+ <entry colname="2">
+ <para>
+ Specify where queries should be logged to.
+ </para>
+ <para>
+ At startup, specifying the category <command>queries</command> will also
+ enable query logging unless <command>querylog</command> option has been
+ specified.
+ </para>
+
+ <para>
+ The query log entry reports the client's IP
+ address and port number, and the query name,
+ class and type. Next it reports whether the
+ Recursion Desired flag was set (+ if set, -
+ if not set), if the query was signed (S),
+ EDNS was in use (E), if TCP was used (T), if
+ DO (DNSSEC Ok) was set (D), or if CD (Checking
+ Disabled) was set (C). After this the
+ destination address the query was sent to is
+ reported.
+ </para>
+
+ <para>
+ <computeroutput>client 127.0.0.1#62536 (www.example.com): query: www.example.com IN AAAA +SE</computeroutput>
+ </para>
+ <para>
+ <computeroutput>client ::1#62537 (www.example.net): query: www.example.net IN AAAA -SE</computeroutput>
+ </para>
+ <para>
+ (The first part of this log message, showing the
+ client address/port number and query name, is
+ repeated in all subsequent log messages related
+ to the same query.)
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para><command>query-errors</command></para>
+ </entry>
+ <entry colname="2">
+ <para>
+ Information about queries that resulted in some
+ failure.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para><command>dispatch</command></para>
+ </entry>
+ <entry colname="2">
+ <para>
+ Dispatching of incoming packets to the
+ server modules where they are to be processed.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para><command>dnssec</command></para>
+ </entry>
+ <entry colname="2">
+ <para>
+ DNSSEC and TSIG protocol processing.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para><command>lame-servers</command></para>
+ </entry>
+ <entry colname="2">
+ <para>
+ Lame servers. These are misconfigurations
+ in remote servers, discovered by BIND 9 when trying to
+ query those servers during resolution.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para><command>delegation-only</command></para>
+ </entry>
+ <entry colname="2">
+ <para>
+ Delegation only. Logs queries that have been
+ forced to NXDOMAIN as the result of a
+ delegation-only zone or a
+ <command>delegation-only</command> in a hint
+ or stub zone declaration.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para><command>edns-disabled</command></para>
+ </entry>
+ <entry colname="2">
+ <para>
+ Log queries that have been forced to use plain
+ DNS due to timeouts. This is often due to
+ the remote servers not being RFC 1034 compliant
+ (not always returning FORMERR or similar to
+ EDNS queries and other extensions to the DNS
+ when they are not understood). In other words, this is
+ targeted at servers that fail to respond to
+ DNS queries that they don't understand.
+ </para>
+ <para>
+ Note: the log message can also be due to
+ packet loss. Before reporting servers for
+ non-RFC 1034 compliance they should be re-tested
+ to determine the nature of the non-compliance.
+ This testing should prevent or reduce the
+ number of false-positive reports.
+ </para>
+ <para>
+ Note: eventually <command>named</command> will have to stop
+ treating such timeouts as due to RFC 1034 non
+ compliance and start treating it as plain
+ packet loss. Falsely classifying packet
+ loss as due to RFC 1034 non compliance impacts
+ on DNSSEC validation which requires EDNS for
+ the DNSSEC records to be returned.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para><command>RPZ</command></para>
+ </entry>
+ <entry colname="2">
+ <para>
+ Information about errors in response policy zone files,
+ rewritten responses, and at the highest
+ <command>debug</command> levels, mere rewriting
+ attempts.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para><command>rate-limit</command></para>
+ </entry>
+ <entry colname="2">
+ <para>
+ The start, periodic, and final notices of the
+ rate limiting of a stream of responses are logged at
+ <command>info</command> severity in this category.
+ These messages include a hash value of the domain name
+ of the response and the name itself,
+ except when there is insufficient memory to record
+ the name for the final notice
+ The final notice is normally delayed until about one
+ minute after rate limit stops.
+ A lack of memory can hurry the final notice,
+ in which case it starts with an asterisk (*).
+ Various internal events are logged at debug 1 level
+ and higher.
+ </para>
+ <para>
+ Rate limiting of individual requests
+ is logged in the <command>query-errors</command> category.
+ </para>
+ </entry>
+ </row>
+ </tbody>
+ </tgroup>
+ </informaltable>
+ </sect3>
+ <sect3>
+ <title>The <command>query-errors</command> Category</title>
+ <para>
+ The <command>query-errors</command> category is
+ specifically intended for debugging purposes: To identify
+ why and how specific queries result in responses which
+ indicate an error.
+ Messages of this category are therefore only logged
+ with <command>debug</command> levels.
+ </para>
+
+ <para>
+ At the debug levels of 1 or higher, each response with the
+ rcode of SERVFAIL is logged as follows:
+ </para>
+ <para>
+ <computeroutput>client 127.0.0.1#61502: query failed (SERVFAIL) for www.example.com/IN/AAAA at query.c:3880</computeroutput>
+ </para>
<para>
This means an error resulting in SERVFAIL was
detected at line 3880 of source file
</para>
<para>
<!-- NOTE: newlines and some spaces added so this would fit on page -->
+ <programlisting>
fetch completed at resolver.c:2970 for www.example.com/A
in 30.000183: timed out/success [domain:example.com,
referral:2,restart:7,qrysent:8,timeout:5,lame:0,neterr:0,
badresp:1,adberr:0,findfail:0,valfail:0]
- </programlisting>
+ </programlisting>
</para>
<para>
The first part before the colon shows that a recursive
following table.
</para>
- <informaltable colsep="0" rowsep="0">
- <tgroup cols="2" colsep="0" rowsep="0" tgroupstyle="4Level-table">
- <colspec colname="1" colnum="1" colsep="0" colwidth="1.150in"/>
- <colspec colname="2" colnum="2" colsep="0" colwidth="3.350in"/>
- <tbody>
- <row rowsep="0">
- <entry colname="1">
-
<para><varname>referral</varname></para>
- </entry>
- <entry colname="2">
+ <informaltable colsep="0" rowsep="0">
+ <tgroup cols="2" colsep="0" rowsep="0" tgroupstyle="4Level-table">
+ <colspec colname="1" colnum="1" colsep="0" colwidth="1.150in"/>
+ <colspec colname="2" colnum="2" colsep="0" colwidth="3.350in"/>
+ <tbody>
+ <row rowsep="0">
+ <entry colname="1">
+ <para><varname>referral</varname></para>
+ </entry>
+ <entry colname="2">
+ <para>
The number of referrals the resolver received
throughout the resolution process.
In the above example this is 2, which are most
likely com and example.com.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
-
<para><varname>restart</varname></para>
- </entry>
- <entry colname="2">
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para><varname>restart</varname></para>
+ </entry>
+ <entry colname="2">
+ <para>
The number of cycles that the resolver tried
remote servers at the <varname>domain</varname>
zone.
(possibly resending it, depending on the response)
to each known name server of
the <varname>domain</varname> zone.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
-
<para><varname>qrysent</varname></para>
- </entry>
- <entry colname="2">
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para><varname>qrysent</varname></para>
+ </entry>
+ <entry colname="2">
+ <para>
The number of queries the resolver sent at the
<varname>domain</varname> zone.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
-
<para><varname>timeout</varname></para>
- </entry>
- <entry colname="2">
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para><varname>timeout</varname></para>
+ </entry>
+ <entry colname="2">
+ <para>
The number of timeouts since the resolver
received the last response.
</para>
</entry>
</row>
- <row rowsep="0">
- <entry colname="1">
-
<para><varname>lame</varname></para>
- </entry>
- <entry colname="2">
+ <row rowsep="0">
+ <entry colname="1">
+ <para><varname>lame</varname></para>
+ </entry>
+ <entry colname="2">
+ <para>
The number of lame servers the resolver detected
at the <varname>domain</varname> zone.
A server is detected to be lame either by an
</para>
</entry>
</row>
- <row rowsep="0">
- <entry colname="1">
-
<para><varname>neterr</varname></para>
- </entry>
- <entry colname="2">
+ <row rowsep="0">
+ <entry colname="1">
+ <para><varname>neterr</varname></para>
+ </entry>
+ <entry colname="2">
+ <para>
The number of erroneous results that the
resolver encountered in sending queries
at the <varname>domain</varname> zone.
</para>
</entry>
</row>
- <row rowsep="0">
- <entry colname="1">
-
<para><varname>badresp</varname></para>
- </entry>
- <entry colname="2">
+ <row rowsep="0">
+ <entry colname="1">
+ <para><varname>badresp</varname></para>
+ </entry>
+ <entry colname="2">
+ <para>
The number of unexpected responses (other than
<varname>lame</varname>) to queries sent by the
resolver at the <varname>domain</varname> zone.
</para>
</entry>
</row>
- <row rowsep="0">
- <entry colname="1">
-
<para><varname>adberr</varname></para>
- </entry>
- <entry colname="2">
+ <row rowsep="0">
+ <entry colname="1">
+ <para><varname>adberr</varname></para>
+ </entry>
+ <entry colname="2">
+ <para>
Failures in finding remote server addresses
of the <varname>domain</varname> zone in the ADB.
One common case of this is that the remote
</para>
</entry>
</row>
- <row rowsep="0">
- <entry colname="1">
-
<para><varname>findfail</varname></para>
- </entry>
- <entry colname="2">
+ <row rowsep="0">
+ <entry colname="1">
+ <para><varname>findfail</varname></para>
+ </entry>
+ <entry colname="2">
+ <para>
Failures of resolving remote server addresses.
This is a total number of failures throughout
the resolution process.
</para>
</entry>
</row>
- <row rowsep="0">
- <entry colname="1">
-
<para><varname>valfail</varname></para>
- </entry>
- <entry colname="2">
+ <row rowsep="0">
+ <entry colname="1">
+ <para><varname>valfail</varname></para>
+ </entry>
+ <entry colname="2">
+ <para>
Failures of DNSSEC validation.
Validation failures are counted throughout
the resolution process (not limited to
</sect2>
<sect2>
- <title><command>lwres</command> Statement Grammar</title>
+ <title><command>lwres</command> Statement Grammar</title>
- This is the grammar of the <command>lwres</command>
- statement in the <filename>named.conf</filename> file:
- </para>
+ <para>
+ This is the grammar of the <command>lwres</command>
+ statement in the <filename>named.conf</filename> file:
+ </para>
<programlisting><command>lwres</command> {
<optional> listen-on { <replaceable>ip_addr</replaceable> <optional>port <replaceable>ip_port</replaceable></optional> <optional>dscp <replaceable>ip_dscp</replaceable></optional> ;
</sect2>
<sect2>
- <title><command>lwres</command> Statement Definition and Usage</title>
-
- The <command>lwres</command> statement configures the
- name
- server to also act as a lightweight resolver server. (See
- <xref linkend="lwresd"/>.) There may be multiple
- <command>lwres</command> statements configuring
- lightweight resolver servers with different properties.
- </para>
-
- The <command>listen-on</command> statement specifies a
- list of
- addresses (and ports) that this instance of a lightweight resolver
- daemon
- should accept requests on. If no port is specified, port 921 is
- used.
- If this statement is omitted, requests will be accepted on
- 127.0.0.1,
- port 921.
- </para>
-
- The <command>view</command> statement binds this
- instance of a
- lightweight resolver daemon to a view in the DNS namespace, so that
- the
- response will be constructed in the same manner as a normal DNS
- query
- matching this view. If this statement is omitted, the default view
- is
- used, and if there is no default view, an error is triggered.
- </para>
-
- The <command>search</command> statement is equivalent to
- the
- <command>search</command> statement in
- <filename>/etc/resolv.conf</filename>. It provides a
- list of domains
- which are appended to relative names in queries.
- </para>
-
- The <command>ndots</command> statement is equivalent to
- the
- <command>ndots</command> statement in
- <filename>/etc/resolv.conf</filename>. It indicates the
- minimum
- number of dots in a relative domain name that should result in an
- exact match lookup before search path elements are appended.
- </para>
+ <title><command>lwres</command> Statement Definition and Usage</title>
+
+ <para>
+ The <command>lwres</command> statement configures the
+ name
+ server to also act as a lightweight resolver server. (See
+ <xref linkend="lwresd"/>.) There may be multiple
+ <command>lwres</command> statements configuring
+ lightweight resolver servers with different properties.
+ </para>
+
+ <para>
+ The <command>listen-on</command> statement specifies a
+ list of
+ addresses (and ports) that this instance of a lightweight resolver
+ daemon
+ should accept requests on. If no port is specified, port 921 is
+ used.
+ If this statement is omitted, requests will be accepted on
+ 127.0.0.1,
+ port 921.
+ </para>
+
+ <para>
+ The <command>view</command> statement binds this
+ instance of a
+ lightweight resolver daemon to a view in the DNS namespace, so that
+ the
+ response will be constructed in the same manner as a normal DNS
+ query
+ matching this view. If this statement is omitted, the default view
+ is
+ used, and if there is no default view, an error is triggered.
+ </para>
+
+ <para>
+ The <command>search</command> statement is equivalent to
+ the
+ <command>search</command> statement in
+ <filename>/etc/resolv.conf</filename>. It provides a
+ list of domains
+ which are appended to relative names in queries.
+ </para>
+
+ <para>
+ The <command>ndots</command> statement is equivalent to
+ the
+ <command>ndots</command> statement in
+ <filename>/etc/resolv.conf</filename>. It indicates the
+ minimum
+ number of dots in a relative domain name that should result in an
+ exact match lookup before search path elements are appended.
+ </para>
</sect2>
<sect2>
- <title><command>masters</command> Statement Grammar</title>
+ <title><command>masters</command> Statement Grammar</title>
<programlisting>
<command>masters</command> <replaceable>name</replaceable> <optional>port <replaceable>ip_port</replaceable></optional> <optional>dscp <replaceable>ip_dscp</replaceable></optional> { ( <replaceable>masters_list</replaceable> |
</sect2>
<sect2>
- <title><command>masters</command> Statement Definition and
- Usage</title>
-
<para><command>masters</command>
+ <title><command>masters</command> Statement Definition and
+ Usage</title>
+ <para><command>masters</command>
lists allow for a common set of masters to be easily used by
- multiple stub and slave zones in their <command>masters</command>
- or <command>also-notify</command> lists.
- </para>
+ multiple stub and slave zones in their <command>masters</command>
+ or <command>also-notify</command> lists.
+ </para>
</sect2>
<sect2>
- <title><command>options</command> Statement Grammar</title>
+ <title><command>options</command> Statement Grammar</title>
- This is the grammar of the <command>options</command>
- statement in the <filename>named.conf</filename> file:
- </para>
+ <para>
+ This is the grammar of the <command>options</command>
+ statement in the <filename>named.conf</filename> file:
+ </para>
<programlisting><command>options</command> {
<optional> attach-cache <replaceable>cache_name</replaceable>; </optional>
<optional> dnssec-validation (<replaceable>yes_or_no</replaceable> | <constant>auto</constant>); </optional>
<optional> dnssec-lookaside ( <replaceable>auto</replaceable> |
<replaceable>no</replaceable> |
- <replaceable>domain</replaceable> trust-anchor <replaceable>domain</replaceable> ); </optional>
+ <replaceable>domain</replaceable> trust-anchor <replaceable>domain</replaceable> ); </optional>
<optional> dnssec-must-be-secure <replaceable>domain yes_or_no</replaceable>; </optional>
<optional> dnssec-accept-expired <replaceable>yes_or_no</replaceable>; </optional>
<optional> forward ( <replaceable>only</replaceable> | <replaceable>first</replaceable> ); </optional>
<optional> forwarders { <optional> <replaceable>ip_addr</replaceable> <optional>port <replaceable>ip_port</replaceable></optional> <optional>dscp <replaceable>ip_dscp</replaceable></optional> ; ... </optional> }; </optional>
<optional> dual-stack-servers <optional>port <replaceable>ip_port</replaceable></optional> <optional>dscp <replaceable>ip_dscp</replaceable></optional> {
- ( <replaceable>domain_name</replaceable> <optional>port <replaceable>ip_port</replaceable></optional> <optional>dscp <replaceable>ip_dscp</replaceable></optional> |
- <replaceable>ip_addr</replaceable> <optional>port <replaceable>ip_port</replaceable></optional> <optional>dscp <replaceable>ip_dscp</replaceable></optional>) ;
- ... }; </optional>
+ ( <replaceable>domain_name</replaceable> <optional>port <replaceable>ip_port</replaceable></optional> <optional>dscp <replaceable>ip_dscp</replaceable></optional> |
+ <replaceable>ip_addr</replaceable> <optional>port <replaceable>ip_port</replaceable></optional> <optional>dscp <replaceable>ip_dscp</replaceable></optional>) ;
+ ... }; </optional>
<optional> check-names ( <replaceable>master</replaceable> | <replaceable>slave</replaceable> | <replaceable>response</replaceable> )
- ( <replaceable>warn</replaceable> | <replaceable>fail</replaceable> | <replaceable>ignore</replaceable> ); </optional>
+ ( <replaceable>warn</replaceable> | <replaceable>fail</replaceable> | <replaceable>ignore</replaceable> ); </optional>
<optional> check-dup-records ( <replaceable>warn</replaceable> | <replaceable>fail</replaceable> | <replaceable>ignore</replaceable> ); </optional>
<optional> check-mx ( <replaceable>warn</replaceable> | <replaceable>fail</replaceable> | <replaceable>ignore</replaceable> ); </optional>
<optional> check-wildcard <replaceable>yes_or_no</replaceable>; </optional>
<optional> listen-on-v6 <optional> port <replaceable>ip_port</replaceable></optional> <optional>dscp <replaceable>ip_dscp</replaceable></optional>
{ <replaceable>address_match_list</replaceable> }; </optional>
<optional> query-source ( ( <replaceable>ip4_addr</replaceable> | <replaceable>*</replaceable> )
- <optional> port ( <replaceable>ip_port</replaceable> | <replaceable>*</replaceable> ) </optional>
- <optional> dscp <replaceable>ip_dscp</replaceable></optional> |
- <optional> address ( <replaceable>ip4_addr</replaceable> | <replaceable>*</replaceable> ) </optional>
- <optional> port ( <replaceable>ip_port</replaceable> | <replaceable>*</replaceable> ) </optional> )
- <optional> dscp <replaceable>ip_dscp</replaceable></optional> ; </optional>
+ <optional> port ( <replaceable>ip_port</replaceable> | <replaceable>*</replaceable> ) </optional>
+ <optional> dscp <replaceable>ip_dscp</replaceable></optional> |
+ <optional> address ( <replaceable>ip4_addr</replaceable> | <replaceable>*</replaceable> ) </optional>
+ <optional> port ( <replaceable>ip_port</replaceable> | <replaceable>*</replaceable> ) </optional> )
+ <optional> dscp <replaceable>ip_dscp</replaceable></optional> ; </optional>
<optional> query-source-v6 ( ( <replaceable>ip6_addr</replaceable> | <replaceable>*</replaceable> )
- <optional> port ( <replaceable>ip_port</replaceable> | <replaceable>*</replaceable> ) </optional>
- <optional> dscp <replaceable>ip_dscp</replaceable></optional> |
- <optional> address ( <replaceable>ip6_addr</replaceable> | <replaceable>*</replaceable> ) </optional>
- <optional> port ( <replaceable>ip_port</replaceable> | <replaceable>*</replaceable> ) </optional> )
- <optional> dscp <replaceable>ip_dscp</replaceable></optional> ; </optional>
+ <optional> port ( <replaceable>ip_port</replaceable> | <replaceable>*</replaceable> ) </optional>
+ <optional> dscp <replaceable>ip_dscp</replaceable></optional> |
+ <optional> address ( <replaceable>ip6_addr</replaceable> | <replaceable>*</replaceable> ) </optional>
+ <optional> port ( <replaceable>ip_port</replaceable> | <replaceable>*</replaceable> ) </optional> )
+ <optional> dscp <replaceable>ip_dscp</replaceable></optional> ; </optional>
<optional> use-queryport-pool <replaceable>yes_or_no</replaceable>; </optional>
<optional> queryport-pool-ports <replaceable>number</replaceable>; </optional>
<optional> queryport-pool-updateinterval <replaceable>number</replaceable>; </optional>
<optional> notify-source-v6 (<replaceable>ip6_addr</replaceable> | <constant>*</constant>) <optional>port <replaceable>ip_port</replaceable></optional> <optional>dscp <replaceable>ip_dscp</replaceable></optional> ; </optional>
<optional> notify-to-soa <replaceable>yes_or_no</replaceable> ; </optional>
<optional> also-notify { <replaceable>ip_addr</replaceable>
- <optional>port <replaceable>ip_port</replaceable></optional> <optional>dscp <replaceable>ip_dscp</replaceable></optional> <optional>key <replaceable>keyname</replaceable></optional> ;
- <optional> <replaceable>ip_addr</replaceable> <optional>port <replaceable>ip_port</replaceable></optional> <optional>dscp <replaceable>ip_dscp</replaceable></optional> <optional>key <replaceable>keyname</replaceable></optional> ; ... </optional> }; </optional>
+ <optional>port <replaceable>ip_port</replaceable></optional> <optional>dscp <replaceable>ip_dscp</replaceable></optional> <optional>key <replaceable>keyname</replaceable></optional> ;
+ <optional> <replaceable>ip_addr</replaceable> <optional>port <replaceable>ip_port</replaceable></optional> <optional>dscp <replaceable>ip_dscp</replaceable></optional> <optional>key <replaceable>keyname</replaceable></optional> ; ... </optional> }; </optional>
<optional> max-ixfr-log-size <replaceable>number</replaceable>; </optional>
<optional> max-journal-size <replaceable>size_spec</replaceable>; </optional>
<optional> coresize <replaceable>size_spec</replaceable> ; </optional>
<optional> dns64 <replaceable>ipv6-prefix</replaceable> {
<optional> clients { <replaceable>address_match_list</replaceable> }; </optional>
<optional> mapped { <replaceable>address_match_list</replaceable> }; </optional>
- <optional> exclude { <replaceable>address_match_list</replaceable> }; </optional>
+ <optional> exclude { <replaceable>address_match_list</replaceable> }; </optional>
<optional> suffix IPv6-address; </optional>
<optional> recursive-only <replaceable>yes_or_no</replaceable>; </optional>
<optional> break-dnssec <replaceable>yes_or_no</replaceable>; </optional>
<optional> root-delegation-only <optional> exclude { <replaceable>namelist</replaceable> } </optional> ; </optional>
<optional> querylog <replaceable>yes_or_no</replaceable> ; </optional>
<optional> disable-algorithms <replaceable>domain</replaceable> { <replaceable>algorithm</replaceable>;
- <optional> <replaceable>algorithm</replaceable>; </optional> }; </optional>
+ <optional> <replaceable>algorithm</replaceable>; </optional> }; </optional>
<optional> disable-ds-digests <replaceable>domain</replaceable> { <replaceable>digest_type</replaceable>;
- <optional> <replaceable>digest_type</replaceable>; </optional> }; </optional>
+ <optional> <replaceable>digest_type</replaceable>; </optional> }; </optional>
<optional> acache-enable <replaceable>yes_or_no</replaceable> ; </optional>
<optional> acache-cleaning-interval <replaceable>number</replaceable>; </optional>
<optional> max-acache-size <replaceable>size_spec</replaceable> ; </optional>
<optional> clients-per-query <replaceable>number</replaceable> ; </optional>
<optional> max-clients-per-query <replaceable>number</replaceable> ; </optional>
<optional> masterfile-format
- (<constant>text</constant>|<constant>raw</constant>|<constant>map</constant>) ; </optional>
+ (<constant>text</constant>|<constant>raw</constant>|<constant>map</constant>) ; </optional>
<optional> empty-server <replaceable>name</replaceable> ; </optional>
<optional> empty-contact <replaceable>name</replaceable> ; </optional>
<optional> empty-zones-enable <replaceable>yes_or_no</replaceable> ; </optional>
</sect2>
<sect2 id="options">
- <title><command>options</command> Statement Definition and
- Usage</title>
-
- The <command>options</command> statement sets up global
- options
-
to be used by <acronym>BIND</acronym>. This statement
- may appear only
- once in a configuration file. If there is no <command>options</command>
- statement, an options block with each option set to its default will
- be used.
- </para>
-
- <variablelist>
-
- <varlistentry>
- <term><command>attach-cache</command></term>
- <listitem>
+ <title><command>options</command> Statement Definition and
+ Usage</title>
+
+ <para>
+ The <command>options</command> statement sets up global
+ options
+ to be used by <acronym>BIND</acronym>. This statement
+ may appear only
+ once in a configuration file. If there is no <command>options</command>
+ statement, an options block with each option set to its default will
+ be used.
+ </para>
+
+ <variablelist>
+
+ <varlistentry>
+ <term><command>attach-cache</command></term>
+ <listitem>
+ <para>
Allows multiple views to share a single cache
database.
Each view has its own cache database by default, but
for name resolution and caching, those views can
share a single cache to save memory and possibly
improve resolution efficiency by using this option.
- </para>
+ </para>
- The <command>attach-cache</command> option
- may also be specified in <command>view</command>
- statements, in which case it overrides the
- global <command>attach-cache</command> option.
- </para>
+ <para>
+ The <command>attach-cache</command> option
+ may also be specified in <command>view</command>
+ statements, in which case it overrides the
+ global <command>attach-cache</command> option.
+ </para>
<para>
The <replaceable>cache_name</replaceable> specifies
configuration differences in different views do
not cause disruption with a shared cache.
</para>
- </listitem>
-
- </varlistentry>
-
- <varlistentry>
- <term><command>directory</command></term>
- <listitem>
- <para>
- The working directory of the server.
- Any non-absolute pathnames in the configuration file will be
- taken
- as relative to this directory. The default location for most
- server
- output files (e.g. <filename>named.run</filename>)
- is this directory.
- If a directory is not specified, the working directory
- defaults to `<filename>.</filename>', the directory from
- which the server
- was started. The directory specified should be an absolute
- path.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>key-directory</command></term>
- <listitem>
- <para>
- When performing dynamic update of secure zones, the
- directory where the public and private DNSSEC key files
- should be found, if different than the current working
- directory. (Note that this option has no effect on the
- paths for files containing non-DNSSEC keys such as
- <filename>bind.keys</filename>,
- <filename>rndc.key</filename> or
- <filename>session.key</filename>.)
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>managed-keys-directory</command></term>
- <listitem>
- <para>
- Specifies the directory in which to store the files that
- track managed DNSSEC keys. By default, this is the working
- directory.
- </para>
- <para>
- If <command>named</command> is not configured to use views,
- then managed keys for the server will be tracked in a single
- file called <filename>managed-keys.bind</filename>.
- Otherwise, managed keys will be tracked in separate files,
- one file per view; each file name will be the SHA256 hash
- of the view name, followed by the extension
- <filename>.mkeys</filename>.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>named-xfer</command></term>
+ </listitem>
+
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>directory</command></term>
<listitem>
<para>
- <emphasis>This option is obsolete.</emphasis> It
- was used in <acronym>BIND</acronym> 8 to specify
- the pathname to the <command>named-xfer</command>
- program. In <acronym>BIND</acronym> 9, no separate
- <command>named-xfer</command> program is needed;
- its functionality is built into the name server.
+ The working directory of the server.
+ Any non-absolute pathnames in the configuration file will be
+ taken
+ as relative to this directory. The default location for most
+ server
+ output files (e.g. <filename>named.run</filename>)
+ is this directory.
+ If a directory is not specified, the working directory
+ defaults to `<filename>.</filename>', the directory from
+ which the server
+ was started. The directory specified should be an absolute
+ path.
</para>
</listitem>
</varlistentry>
<varlistentry>
- <term><command>tkey-gssapi-keytab</command></term>
+ <term><command>key-directory</command></term>
<listitem>
<para>
- The KRB5 keytab file to use for GSS-TSIG updates. If
+ When performing dynamic update of secure zones, the
+ directory where the public and private DNSSEC key files
+ should be found, if different than the current working
+ directory. (Note that this option has no effect on the
+ paths for files containing non-DNSSEC keys such as
+ <filename>bind.keys</filename>,
+ <filename>rndc.key</filename> or
+ <filename>session.key</filename>.)
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>managed-keys-directory</command></term>
+ <listitem>
+ <para>
+ Specifies the directory in which to store the files that
+ track managed DNSSEC keys. By default, this is the working
+ directory.
+ </para>
+ <para>
+ If <command>named</command> is not configured to use views,
+ then managed keys for the server will be tracked in a single
+ file called <filename>managed-keys.bind</filename>.
+ Otherwise, managed keys will be tracked in separate files,
+ one file per view; each file name will be the SHA256 hash
+ of the view name, followed by the extension
+ <filename>.mkeys</filename>.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>named-xfer</command></term>
+ <listitem>
+ <para>
+ <emphasis>This option is obsolete.</emphasis> It
+ was used in <acronym>BIND</acronym> 8 to specify
+ the pathname to the <command>named-xfer</command>
+ program. In <acronym>BIND</acronym> 9, no separate
+ <command>named-xfer</command> program is needed;
+ its functionality is built into the name server.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>tkey-gssapi-keytab</command></term>
+ <listitem>
+ <para>
+ The KRB5 keytab file to use for GSS-TSIG updates. If
this option is set and tkey-gssapi-credential is not
set, then updates will be allowed with any key
matching a principal in the specified keytab.
</listitem>
</varlistentry>
- <varlistentry>
- <term><command>tkey-domain</command></term>
+ <varlistentry>
+ <term><command>tkey-domain</command></term>
<listitem>
<para>
The domain appended to the names of all shared keys
</listitem>
</varlistentry>
- <varlistentry>
- <term><command>tkey-dhkey</command></term>
- <listitem>
- The Diffie-Hellman key used by the server
- to generate shared keys with clients using the Diffie-Hellman
- mode
- of <command>TKEY</command>. The server must be
- able to load the
- public and private keys from files in the working directory.
- In
- most cases, the keyname should be the server's host name.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>cache-file</command></term>
- <listitem>
+ <varlistentry>
+ <term><command>tkey-dhkey</command></term>
+ <listitem>
+ <para>
+ The Diffie-Hellman key used by the server
+ to generate shared keys with clients using the Diffie-Hellman
+ mode
+ of <command>TKEY</command>. The server must be
+ able to load the
+ public and private keys from files in the working directory.
+ In
+ most cases, the keyname should be the server's host name.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>cache-file</command></term>
+ <listitem>
+ <para>
This is for testing only. Do not use.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>dump-file</command></term>
- <listitem>
- The pathname of the file the server dumps
- the database to when instructed to do so with
- <command>rndc dumpdb</command>.
- If not specified, the default is <filename>named_dump.db</filename>.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>memstatistics-file</command></term>
- <listitem>
- The pathname of the file the server writes memory
- usage statistics to on exit. If not specified,
- the default is <filename>named.memstats</filename>.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>pid-file</command></term>
- <listitem>
- The pathname of the file the server writes its process ID
- in. If not specified, the default is
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>dump-file</command></term>
+ <listitem>
+ <para>
+ The pathname of the file the server dumps
+ the database to when instructed to do so with
+ <command>rndc dumpdb</command>.
+ If not specified, the default is <filename>named_dump.db</filename>.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>memstatistics-file</command></term>
+ <listitem>
+ <para>
+ The pathname of the file the server writes memory
+ usage statistics to on exit. If not specified,
+ the default is <filename>named.memstats</filename>.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>pid-file</command></term>
+ <listitem>
+ <para>
+ The pathname of the file the server writes its process ID
+ in. If not specified, the default is
<filename>/var/run/named/named.pid</filename>.
- The PID file is used by programs that want to send signals to
- the running
- name server. Specifying <command>pid-file none</command> disables the
- use of a PID file — no file will be written and any
- existing one will be removed. Note that <command>none</command>
- is a keyword, not a filename, and therefore is not enclosed
- in
- double quotes.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>recursing-file</command></term>
- <listitem>
- The pathname of the file the server dumps
- the queries that are currently recursing when instructed
- to do so with <command>rndc recursing</command>.
- If not specified, the default is <filename>named.recursing</filename>.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>statistics-file</command></term>
- <listitem>
- The pathname of the file the server appends statistics
- to when instructed to do so using <command>rndc stats</command>.
- If not specified, the default is <filename>named.stats</filename> in the
- server's current directory. The format of the file is
- described
- in <xref linkend="statsfile"/>.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>bindkeys-file</command></term>
- <listitem>
- The pathname of a file to override the built-in trusted
+ The PID file is used by programs that want to send signals to
+ the running
+ name server. Specifying <command>pid-file none</command> disables the
+ use of a PID file — no file will be written and any
+ existing one will be removed. Note that <command>none</command>
+ is a keyword, not a filename, and therefore is not enclosed
+ in
+ double quotes.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>recursing-file</command></term>
+ <listitem>
+ <para>
+ The pathname of the file the server dumps
+ the queries that are currently recursing when instructed
+ to do so with <command>rndc recursing</command>.
+ If not specified, the default is <filename>named.recursing</filename>.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>statistics-file</command></term>
+ <listitem>
+ <para>
+ The pathname of the file the server appends statistics
+ to when instructed to do so using <command>rndc stats</command>.
+ If not specified, the default is <filename>named.stats</filename> in the
+ server's current directory. The format of the file is
+ described
+ in <xref linkend="statsfile"/>.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>bindkeys-file</command></term>
+ <listitem>
+ <para>
+ The pathname of a file to override the built-in trusted
keys provided by <command>named</command>.
See the discussion of <command>dnssec-lookaside</command>
- and <command>dnssec-validation</command> for details.
- If not specified, the default is
+ and <command>dnssec-validation</command> for details.
+ If not specified, the default is
<filename>/etc/bind.keys</filename>.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>secroots-file</command></term>
- <listitem>
- The pathname of the file the server dumps
- security roots to when instructed to do so with
- <command>rndc secroots</command>.
- If not specified, the default is
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>secroots-file</command></term>
+ <listitem>
+ <para>
+ The pathname of the file the server dumps
+ security roots to when instructed to do so with
+ <command>rndc secroots</command>.
+ If not specified, the default is
<filename>named.secroots</filename>.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>session-keyfile</command></term>
- <listitem>
- The pathname of the file into which to write a TSIG
- session key generated by <command>named</command> for use by
- <command>nsupdate -l</command>. If not specified, the
- default is <filename>/var/run/named/session.key</filename>.
- (See <xref linkend="dynamic_update_policies"/>, and in
- particular the discussion of the
- <command>update-policy</command> statement's
- <userinput>local</userinput> option for more
- information about this feature.)
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>session-keyname</command></term>
- <listitem>
- The key name to use for the TSIG session key.
- If not specified, the default is "local-ddns".
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>session-keyalg</command></term>
- <listitem>
- The algorithm to use for the TSIG session key.
- Valid values are hmac-sha1, hmac-sha224, hmac-sha256,
- hmac-sha384, hmac-sha512 and hmac-md5. If not
- specified, the default is hmac-sha256.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>port</command></term>
- <listitem>
- The UDP/TCP port number the server uses for
- receiving and sending DNS protocol traffic.
- The default is 53. This option is mainly intended for server
- testing;
- a server using a port other than 53 will not be able to
- communicate with
- the global DNS.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>random-device</command></term>
- <listitem>
- The source of entropy to be used by the server. Entropy is
- primarily needed
- for DNSSEC operations, such as TKEY transactions and dynamic
- update of signed
- zones. This options specifies the device (or file) from which
- to read
- entropy. If this is a file, operations requiring entropy will
- fail when the
- file has been exhausted. If not specified, the default value
- is
- <filename>/dev/random</filename>
- (or equivalent) when present, and none otherwise. The
- <command>random-device</command> option takes
- effect during
- the initial configuration load at server startup time and
- is ignored on subsequent reloads.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>preferred-glue</command></term>
- <listitem>
- If specified, the listed type (A or AAAA) will be emitted
- before other glue
- in the additional section of a query response.
- The default is not to prefer any type (NONE).
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry id="root_delegation_only">
- <term><command>root-delegation-only</command></term>
- <listitem>
- Turn on enforcement of delegation-only in TLDs
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>session-keyfile</command></term>
+ <listitem>
+ <para>
+ The pathname of the file into which to write a TSIG
+ session key generated by <command>named</command> for use by
+ <command>nsupdate -l</command>. If not specified, the
+ default is <filename>/var/run/named/session.key</filename>.
+ (See <xref linkend="dynamic_update_policies"/>, and in
+ particular the discussion of the
+ <command>update-policy</command> statement's
+ <userinput>local</userinput> option for more
+ information about this feature.)
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>session-keyname</command></term>
+ <listitem>
+ <para>
+ The key name to use for the TSIG session key.
+ If not specified, the default is "local-ddns".
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>session-keyalg</command></term>
+ <listitem>
+ <para>
+ The algorithm to use for the TSIG session key.
+ Valid values are hmac-sha1, hmac-sha224, hmac-sha256,
+ hmac-sha384, hmac-sha512 and hmac-md5. If not
+ specified, the default is hmac-sha256.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>port</command></term>
+ <listitem>
+ <para>
+ The UDP/TCP port number the server uses for
+ receiving and sending DNS protocol traffic.
+ The default is 53. This option is mainly intended for server
+ testing;
+ a server using a port other than 53 will not be able to
+ communicate with
+ the global DNS.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>random-device</command></term>
+ <listitem>
+ <para>
+ The source of entropy to be used by the server. Entropy is
+ primarily needed
+ for DNSSEC operations, such as TKEY transactions and dynamic
+ update of signed
+ zones. This options specifies the device (or file) from which
+ to read
+ entropy. If this is a file, operations requiring entropy will
+ fail when the
+ file has been exhausted. If not specified, the default value
+ is
+ <filename>/dev/random</filename>
+ (or equivalent) when present, and none otherwise. The
+ <command>random-device</command> option takes
+ effect during
+ the initial configuration load at server startup time and
+ is ignored on subsequent reloads.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>preferred-glue</command></term>
+ <listitem>
+ <para>
+ If specified, the listed type (A or AAAA) will be emitted
+ before other glue
+ in the additional section of a query response.
+ The default is not to prefer any type (NONE).
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry id="root_delegation_only">
+ <term><command>root-delegation-only</command></term>
+ <listitem>
+ <para>
+ Turn on enforcement of delegation-only in TLDs
(top level domains) and root zones with an optional
exclude list.
- </para>
+ </para>
<para>
DS queries are expected to be made to and be answered by
delegation only zones. Such queries and responses are
(no records at the name) in the delegation only zone
when the query type is not ANY.
</para>
- Note some TLDs are not delegation only (e.g. "DE", "LV",
+ <para>
+ Note some TLDs are not delegation only (e.g. "DE", "LV",
"US" and "MUSEUM"). This list is not exhaustive.
- </para>
+ </para>
<programlisting>
options {
};
</programlisting>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>disable-algorithms</command></term>
- <listitem>
- Disable the specified DNSSEC algorithms at and below the
- specified name.
- Multiple <command>disable-algorithms</command>
- statements are allowed.
- Only the best match <command>disable-algorithms</command>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>disable-algorithms</command></term>
+ <listitem>
+ <para>
+ Disable the specified DNSSEC algorithms at and below the
+ specified name.
+ Multiple <command>disable-algorithms</command>
+ statements are allowed.
+ Only the best match <command>disable-algorithms</command>
clause will be used to determine which algorithms are used.
- </para>
+ </para>
+ <para>
If all supported algorithms are disabled, the zones covered
by the <command>disable-algorithms</command> will be treated
as insecure.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>disable-ds-digests</command></term>
- <listitem>
- Disable the specified DS/DLV digest types at and below the
- specified name.
- Multiple <command>disable-ds-digests</command>
- statements are allowed.
- Only the best match <command>disable-ds-digests</command>
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>disable-ds-digests</command></term>
+ <listitem>
+ <para>
+ Disable the specified DS/DLV digest types at and below the
+ specified name.
+ Multiple <command>disable-ds-digests</command>
+ statements are allowed.
+ Only the best match <command>disable-ds-digests</command>
clause will be used to determine which digest types are used.
- </para>
+ </para>
<para>
If all supported digest types are disabled, the zones covered
by the <command>disable-ds-digests</command> will be treated
as insecure.
</para>
- </listitem>
- </varlistentry>
+ </listitem>
+ </varlistentry>
- <varlistentry>
- <term><command>dnssec-lookaside</command></term>
- <listitem>
+ <varlistentry>
+ <term><command>dnssec-lookaside</command></term>
+ <listitem>
+ <para>
When set, <command>dnssec-lookaside</command> provides the
validator with an alternate method to validate DNSKEY
records at the top of a zone. When a DNSKEY is at or
will be appended to the key name and a DLV record will be
looked up to see if it can validate the key. If the DLV
record validates a DNSKEY (similarly to the way a DS
- record does) the DNSKEY RRset is deemed to be trusted.
+ record does) the DNSKEY RRset is deemed to be trusted.
</para>
<para>
If <command>dnssec-lookaside</command> is set to
<userinput>no</userinput>, then dnssec-lookaside
is not used.
</para>
- The default DLV key is stored in the file
- <filename>bind.keys</filename>;
- <command>named</command> will load that key at
- startup if <command>dnssec-lookaside</command> is set to
- <constant>auto</constant>. A copy of the file is
-
installed along with <acronym>BIND</acronym> 9, and is
- current as of the release date. If the DLV key expires, a
- new copy of <filename>bind.keys</filename> can be downloaded
-
from <ulink url="https://www.isc.org/solutions/dlv/"
+ <para>
+ The default DLV key is stored in the file
+ <filename>bind.keys</filename>;
+ <command>named</command> will load that key at
+ startup if <command>dnssec-lookaside</command> is set to
+ <constant>auto</constant>. A copy of the file is
+ installed along with <acronym>BIND</acronym> 9, and is
+ current as of the release date. If the DLV key expires, a
+ new copy of <filename>bind.keys</filename> can be downloaded
+ from <ulink url="https://www.isc.org/solutions/dlv/"
>https://www.isc.org/solutions/dlv/</ulink>.
- </para>
- (To prevent problems if <filename>bind.keys</filename> is
- not found, the current key is also compiled in to
- <command>named</command>. Relying on this is not
- recommended, however, as it requires <command>named</command>
- to be recompiled with a new key when the DLV key expires.)
- </para>
- NOTE: <command>named</command> only loads certain specific
- keys from <filename>bind.keys</filename>: those for the
- DLV zone and for the DNS root zone. The file cannot be
- used to store keys for other zones.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>dnssec-must-be-secure</command></term>
- <listitem>
- Specify hierarchies which must be or may not be secure
- (signed and validated). If <userinput>yes</userinput>,
- then <command>named</command> will only accept answers if
- they are secure. If <userinput>no</userinput>, then normal
- DNSSEC validation applies allowing for insecure answers to
- be accepted. The specified domain must be under a
- <command>trusted-keys</command> or
- <command>managed-keys</command> statement, or
- <command>dnssec-lookaside</command> must be active.
- </para>
- </listitem>
- </varlistentry>
+ </para>
+ <para>
+ (To prevent problems if <filename>bind.keys</filename> is
+ not found, the current key is also compiled in to
+ <command>named</command>. Relying on this is not
+ recommended, however, as it requires <command>named</command>
+ to be recompiled with a new key when the DLV key expires.)
+ </para>
+ <para>
+ NOTE: <command>named</command> only loads certain specific
+ keys from <filename>bind.keys</filename>: those for the
+ DLV zone and for the DNS root zone. The file cannot be
+ used to store keys for other zones.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>dnssec-must-be-secure</command></term>
+ <listitem>
+ <para>
+ Specify hierarchies which must be or may not be secure
+ (signed and validated). If <userinput>yes</userinput>,
+ then <command>named</command> will only accept answers if
+ they are secure. If <userinput>no</userinput>, then normal
+ DNSSEC validation applies allowing for insecure answers to
+ be accepted. The specified domain must be under a
+ <command>trusted-keys</command> or
+ <command>managed-keys</command> statement, or
+ <command>dnssec-lookaside</command> must be active.
+ </para>
+ </listitem>
+ </varlistentry>
<varlistentry>
<term><command>dns64</command></term>
- <listitem>
+ <listitem>
<para>
This directive instructs <command>named</command> to
return mapped IPv4 addresses to AAAA queries when
<para>
Each <command>dns64</command> supports an optional
<command>clients</command> ACL that determines which
- clients are affected by this directive. If not defined,
- it defaults to <userinput>any;</userinput>.
+ clients are affected by this directive. If not defined,
+ it defaults to <userinput>any;</userinput>.
</para>
<para>
Each <command>dns64</command> supports an optional
<programlisting>
acl rfc1918 { 10/8; 192.168/16; 172.16/12; };
- dns64 64:FF9B::/96 {
- clients { any; };
- mapped { !rfc1918; any; };
- exclude { 64:FF9B::/96; ::ffff:0000:0000/96; };
- suffix ::;
- };
+ dns64 64:FF9B::/96 {
+ clients { any; };
+ mapped { !rfc1918; any; };
+ exclude { 64:FF9B::/96; ::ffff:0000:0000/96; };
+ suffix ::;
+ };
</programlisting>
- </listitem>
+ </listitem>
</varlistentry>
<varlistentry>
<term><command>dnssec-update-mode</command></term>
<listitem>
- <para>
- If this option is set to its default value of
- <literal>maintain</literal> in a zone of type
- <literal>master</literal> which is DNSSEC-signed
- and configured to allow dynamic updates (see
- <xref linkend="dynamic_update_policies"/>), and
- if <command>named</command> has access to the
- private signing key(s) for the zone, then
- <command>named</command> will automatically sign all new
- or changed records and maintain signatures for the zone
- by regenerating RRSIG records whenever they approach
- their expiration date.
- </para>
- <para>
- If the option is changed to <literal>no-resign</literal>,
- then <command>named</command> will sign all new or
- changed records, but scheduled maintenance of
- signatures is disabled.
- </para>
- With either of these settings, <command>named</command>
- will reject updates to a DNSSEC-signed zone when the
- signing keys are inactive or unavailable to
- <command>named</command>. (A planned third option,
- <literal>external</literal>, will disable all automatic
- signing and allow DNSSEC data to be submitted into a zone
- via dynamic update; this is not yet implemented.)
+ <para>
+ If this option is set to its default value of
+ <literal>maintain</literal> in a zone of type
+ <literal>master</literal> which is DNSSEC-signed
+ and configured to allow dynamic updates (see
+ <xref linkend="dynamic_update_policies"/>), and
+ if <command>named</command> has access to the
+ private signing key(s) for the zone, then
+ <command>named</command> will automatically sign all new
+ or changed records and maintain signatures for the zone
+ by regenerating RRSIG records whenever they approach
+ their expiration date.
+ </para>
+ <para>
+ If the option is changed to <literal>no-resign</literal>,
+ then <command>named</command> will sign all new or
+ changed records, but scheduled maintenance of
+ signatures is disabled.
+ </para>
+ <para>
+ With either of these settings, <command>named</command>
+ will reject updates to a DNSSEC-signed zone when the
+ signing keys are inactive or unavailable to
+ <command>named</command>. (A planned third option,
+ <literal>external</literal>, will disable all automatic
+ signing and allow DNSSEC data to be submitted into a zone
+ via dynamic update; this is not yet implemented.)
</para>
</listitem>
</varlistentry>
- <varlistentry>
- <term><command>zone-statistics</command></term>
- <listitem>
- <para>
- If <userinput>full</userinput>, the server will collect
- statistical data on all zones (unless specifically
- turned off on a per-zone basis by specifying
- <command>zone-statistics terse</command> or
- <command>zone-statistics none</command>
- in the <command>zone</command> statement).
- The default is <userinput>terse</userinput>, providing
- minimal statistics on zones (including name and
- current serial number, but not query type
- counters).
- </para>
- <para>
- These statistics may be accessed via the
- <command>statistics-channel</command> or
- using <command>rndc stats</command>, which
- will dump them to the file listed
- in the <command>statistics-file</command>. See
- also <xref linkend="statsfile"/>.
- </para>
- <para>
- For backward compatibility with earlier versions
- of BIND 9, the <command>zone-statistics</command>
- option can also accept <userinput>yes</userinput>
- or <userinput>no</userinput>; <userinput>yes</userinput>
- has the same meaning as <userinput>full</userinput>.
- As of <acronym>BIND</acronym> 9.10,
- <userinput>no</userinput> has the same meaning
- as <userinput>none</userinput>; previously, it
- was the same as <userinput>terse</userinput>.
- </para>
- </listitem>
- </varlistentry>
- </variablelist>
-
- <sect3 id="boolean_options">
- <title>Boolean Options</title>
-
- <variablelist>
-
- <varlistentry>
- <term><command>allow-new-zones</command></term>
- <listitem>
- <para>
- If <userinput>yes</userinput>, then zones can be
- added at runtime via <command>rndc addzone</command>
- or deleted via <command>rndc delzone</command>.
- The default is <userinput>no</userinput>.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>auth-nxdomain</command></term>
- <listitem>
- <para>
- If <userinput>yes</userinput>, then the <command>AA</command> bit
- is always set on NXDOMAIN responses, even if the server is
- not actually
- authoritative. The default is <userinput>no</userinput>;
- this is
- a change from <acronym>BIND</acronym> 8. If you
- are using very old DNS software, you
- may need to set it to <userinput>yes</userinput>.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>deallocate-on-exit</command></term>
- <listitem>
- <para>
- This option was used in <acronym>BIND</acronym>
- 8 to enable checking
- for memory leaks on exit. <acronym>BIND</acronym> 9 ignores the option and always performs
- the checks.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>memstatistics</command></term>
- <listitem>
- <para>
- Write memory statistics to the file specified by
- <command>memstatistics-file</command> at exit.
- The default is <userinput>no</userinput> unless
- '-m record' is specified on the command line in
- which case it is <userinput>yes</userinput>.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>dialup</command></term>
- <listitem>
- <para>
- If <userinput>yes</userinput>, then the
- server treats all zones as if they are doing zone transfers
- across
- a dial-on-demand dialup link, which can be brought up by
- traffic
- originating from this server. This has different effects
- according
- to zone type and concentrates the zone maintenance so that
- it all
- happens in a short interval, once every <command>heartbeat-interval</command> and
- hopefully during the one call. It also suppresses some of
- the normal
- zone maintenance traffic. The default is <userinput>no</userinput>.
- </para>
- <para>
- The <command>dialup</command> option
- may also be specified in the <command>view</command> and
- <command>zone</command> statements,
- in which case it overrides the global <command>dialup</command>
- option.
- </para>
- <para>
- If the zone is a master zone, then the server will send out a
- NOTIFY
- request to all the slaves (default). This should trigger the
- zone serial
- number check in the slave (providing it supports NOTIFY)
- allowing the slave
- to verify the zone while the connection is active.
- The set of servers to which NOTIFY is sent can be controlled
- by
- <command>notify</command> and <command>also-notify</command>.
- </para>
- <para>
- If the
- zone is a slave or stub zone, then the server will suppress
- the regular
- "zone up to date" (refresh) queries and only perform them
- when the
- <command>heartbeat-interval</command> expires in
- addition to sending
- NOTIFY requests.
- </para>
- <para>
- Finer control can be achieved by using
- <userinput>notify</userinput> which only sends NOTIFY
- messages,
- <userinput>notify-passive</userinput> which sends NOTIFY
- messages and
- suppresses the normal refresh queries, <userinput>refresh</userinput>
- which suppresses normal refresh processing and sends refresh
- queries
- when the <command>heartbeat-interval</command>
- expires, and
- <userinput>passive</userinput> which just disables normal
- refresh
- processing.
- </para>
-
- <informaltable colsep="0" rowsep="0">
- <tgroup cols="4" colsep="0" rowsep="0" tgroupstyle="4Level-table">
- <colspec colname="1" colnum="1" colsep="0" colwidth="1.150in"/>
- <colspec colname="2" colnum="2" colsep="0" colwidth="1.150in"/>
- <colspec colname="3" colnum="3" colsep="0" colwidth="1.150in"/>
- <colspec colname="4" colnum="4" colsep="0" colwidth="1.150in"/>
- <tbody>
- <row rowsep="0">
- <entry colname="1">
- <para>
- dialup mode
- </para>
- </entry>
- <entry colname="2">
- <para>
- normal refresh
- </para>
- </entry>
- <entry colname="3">
- <para>
- heart-beat refresh
- </para>
- </entry>
- <entry colname="4">
- <para>
- heart-beat notify
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para><command>no</command> (default)</para>
- </entry>
- <entry colname="2">
- <para>
- yes
- </para>
- </entry>
- <entry colname="3">
- <para>
- no
- </para>
- </entry>
- <entry colname="4">
- <para>
- no
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para><command>yes</command></para>
- </entry>
- <entry colname="2">
- <para>
- no
- </para>
- </entry>
- <entry colname="3">
- <para>
- yes
- </para>
- </entry>
- <entry colname="4">
- <para>
- yes
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para><command>notify</command></para>
- </entry>
- <entry colname="2">
- <para>
- yes
- </para>
- </entry>
- <entry colname="3">
- <para>
- no
- </para>
- </entry>
- <entry colname="4">
- <para>
- yes
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para><command>refresh</command></para>
- </entry>
- <entry colname="2">
- <para>
- no
- </para>
- </entry>
- <entry colname="3">
- <para>
- yes
- </para>
- </entry>
- <entry colname="4">
- <para>
- no
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para><command>passive</command></para>
- </entry>
- <entry colname="2">
- <para>
- no
- </para>
- </entry>
- <entry colname="3">
- <para>
- no
- </para>
- </entry>
- <entry colname="4">
- <para>
- no
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para><command>notify-passive</command></para>
- </entry>
- <entry colname="2">
- <para>
- no
- </para>
- </entry>
- <entry colname="3">
- <para>
- no
- </para>
- </entry>
- <entry colname="4">
- <para>
- yes
- </para>
- </entry>
- </row>
- </tbody>
- </tgroup>
- </informaltable>
-
- <para>
- Note that normal NOTIFY processing is not affected by
- <command>dialup</command>.
- </para>
-
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>fake-iquery</command></term>
- <listitem>
- <para>
- In <acronym>BIND</acronym> 8, this option
- enabled simulating the obsolete DNS query type
- IQUERY. <acronym>BIND</acronym> 9 never does
- IQUERY simulation.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>fetch-glue</command></term>
- <listitem>
- <para>
- This option is obsolete.
- In BIND 8, <userinput>fetch-glue yes</userinput>
- caused the server to attempt to fetch glue resource records
- it
- didn't have when constructing the additional
- data section of a response. This is now considered a bad
- idea
- and BIND 9 never does it.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>flush-zones-on-shutdown</command></term>
- <listitem>
- <para>
- When the nameserver exits due receiving SIGTERM,
- flush or do not flush any pending zone writes. The default
- is
- <command>flush-zones-on-shutdown</command> <userinput>no</userinput>.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>has-old-clients</command></term>
- <listitem>
- <para>
- This option was incorrectly implemented
- in <acronym>BIND</acronym> 8, and is ignored by <acronym>BIND</acronym> 9.
- To achieve the intended effect
- of
- <command>has-old-clients</command> <userinput>yes</userinput>, specify
- the two separate options <command>auth-nxdomain</command> <userinput>yes</userinput>
- and <command>rfc2308-type1</command> <userinput>no</userinput> instead.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>host-statistics</command></term>
- <listitem>
- <para>
- In BIND 8, this enables keeping of
- statistics for every host that the name server interacts
- with.
- Not implemented in BIND 9.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>maintain-ixfr-base</command></term>
- <listitem>
- <para>
- <emphasis>This option is obsolete</emphasis>.
- It was used in <acronym>BIND</acronym> 8 to
- determine whether a transaction log was
- kept for Incremental Zone Transfer. <acronym>BIND</acronym> 9 maintains a transaction
- log whenever possible. If you need to disable outgoing
- incremental zone
- transfers, use <command>provide-ixfr</command> <userinput>no</userinput>.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>minimal-responses</command></term>
- <listitem>
- <para>
- If <userinput>yes</userinput>, then when generating
- responses the server will only add records to the authority
- and additional data sections when they are required (e.g.
- delegations, negative responses). This may improve the
- performance of the server.
- The default is <userinput>no</userinput>.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>multiple-cnames</command></term>
- <listitem>
- <para>
- This option was used in <acronym>BIND</acronym> 8 to allow
- a domain name to have multiple CNAME records in violation of
- the DNS standards. <acronym>BIND</acronym> 9.2 onwards
- always strictly enforces the CNAME rules both in master
- files and dynamic updates.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>notify</command></term>
- <listitem>
- <para>
- If <userinput>yes</userinput> (the default),
- DNS NOTIFY messages are sent when a zone the server is
- authoritative for
- changes, see <xref linkend="notify"/>. The messages are
- sent to the
- servers listed in the zone's NS records (except the master
- server identified
- in the SOA MNAME field), and to any servers listed in the
- <command>also-notify</command> option.
- </para>
- <para>
- If <userinput>master-only</userinput>, notifies are only
- sent
- for master zones.
- If <userinput>explicit</userinput>, notifies are sent only
- to
- servers explicitly listed using <command>also-notify</command>.
- If <userinput>no</userinput>, no notifies are sent.
- </para>
- <para>
- The <command>notify</command> option may also be
- specified in the <command>zone</command>
- statement,
- in which case it overrides the <command>options notify</command> statement.
- It would only be necessary to turn off this option if it
- caused slaves
- to crash.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>notify-to-soa</command></term>
- <listitem>
- <para>
- If <userinput>yes</userinput> do not check the nameservers
- in the NS RRset against the SOA MNAME. Normally a NOTIFY
- message is not sent to the SOA MNAME (SOA ORIGIN) as it is
- supposed to contain the name of the ultimate master.
- Sometimes, however, a slave is listed as the SOA MNAME in
- hidden master configurations and in that case you would
- want the ultimate master to still send NOTIFY messages to
- all the nameservers listed in the NS RRset.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>recursion</command></term>
- <listitem>
- <para>
- If <userinput>yes</userinput>, and a
- DNS query requests recursion, then the server will attempt
- to do
- all the work required to answer the query. If recursion is
- off
- and the server does not already know the answer, it will
- return a
- referral response. The default is
- <userinput>yes</userinput>.
- Note that setting <command>recursion no</command> does not prevent
- clients from getting data from the server's cache; it only
- prevents new data from being cached as an effect of client
- queries.
- Caching may still occur as an effect the server's internal
- operation, such as NOTIFY address lookups.
- See also <command>fetch-glue</command> above.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>request-nsid</command></term>
- <listitem>
- <para>
- If <userinput>yes</userinput>, then an empty EDNS(0)
- NSID (Name Server Identifier) option is sent with all
- queries to authoritative name servers during iterative
- resolution. If the authoritative server returns an NSID
- option in its response, then its contents are logged in
- the <command>resolver</command> category at level
- <command>info</command>.
- The default is <userinput>no</userinput>.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>rfc2308-type1</command></term>
- <listitem>
- <para>
- Setting this to <userinput>yes</userinput> will
- cause the server to send NS records along with the SOA
- record for negative
- answers. The default is <userinput>no</userinput>.
- </para>
- <note>
- <simpara>
- Not yet implemented in <acronym>BIND</acronym>
- 9.
- </simpara>
- </note>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>use-id-pool</command></term>
- <listitem>
- <para>
- <emphasis>This option is obsolete</emphasis>.
- <acronym>BIND</acronym> 9 always allocates query
- IDs from a pool.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>use-ixfr</command></term>
- <listitem>
- <para>
- <emphasis>This option is obsolete</emphasis>.
- If you need to disable IXFR to a particular server or
- servers, see
- the information on the <command>provide-ixfr</command> option
- in <xref linkend="server_statement_definition_and_usage"/>.
- See also
- <xref linkend="incremental_zone_transfers"/>.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>provide-ixfr</command></term>
- <listitem>
- <para>
- See the description of
- <command>provide-ixfr</command> in
- <xref linkend="server_statement_definition_and_usage"/>.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>request-ixfr</command></term>
- <listitem>
- <para>
- See the description of
- <command>request-ixfr</command> in
- <xref linkend="server_statement_definition_and_usage"/>.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>treat-cr-as-space</command></term>
- <listitem>
- <para>
- This option was used in <acronym>BIND</acronym>
- 8 to make
- the server treat carriage return ("<command>\r</command>") characters the same way
- as a space or tab character,
- to facilitate loading of zone files on a UNIX system that
- were generated
- on an NT or DOS machine. In <acronym>BIND</acronym> 9, both UNIX "<command>\n</command>"
- and NT/DOS "<command>\r\n</command>" newlines
- are always accepted,
- and the option is ignored.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>additional-from-auth</command></term>
- <term><command>additional-from-cache</command></term>
- <listitem>
-
- <para>
- These options control the behavior of an authoritative
- server when
- answering queries which have additional data, or when
- following CNAME
- and DNAME chains.
- </para>
-
- <para>
- When both of these options are set to <userinput>yes</userinput>
- (the default) and a
- query is being answered from authoritative data (a zone
- configured into the server), the additional data section of
- the
- reply will be filled in using data from other authoritative
- zones
- and from the cache. In some situations this is undesirable,
- such
- as when there is concern over the correctness of the cache,
- or
- in servers where slave zones may be added and modified by
- untrusted third parties. Also, avoiding
- the search for this additional data will speed up server
- operations
- at the possible expense of additional queries to resolve
- what would
- otherwise be provided in the additional section.
- </para>
-
- <para>
- For example, if a query asks for an MX record for host <literal>foo.example.com</literal>,
- and the record found is "<literal>MX 10 mail.example.net</literal>", normally the address
- records (A and AAAA) for <literal>mail.example.net</literal> will be provided as well,
- if known, even though they are not in the example.com zone.
- Setting these options to <command>no</command>
- disables this behavior and makes
- the server only search for additional data in the zone it
- answers from.
- </para>
-
- <para>
- These options are intended for use in authoritative-only
- servers, or in authoritative-only views. Attempts to set
- them to <command>no</command> without also
- specifying
- <command>recursion no</command> will cause the
- server to
- ignore the options and log a warning message.
- </para>
-
- <para>
- Specifying <command>additional-from-cache no</command> actually
- disables the use of the cache not only for additional data
- lookups
- but also when looking up the answer. This is usually the
- desired
- behavior in an authoritative-only server where the
- correctness of
- the cached data is an issue.
- </para>
-
- <para>
- When a name server is non-recursively queried for a name
- that is not
- below the apex of any served zone, it normally answers with
- an
- "upwards referral" to the root servers or the servers of
- some other
- known parent of the query name. Since the data in an
- upwards referral
- comes from the cache, the server will not be able to provide
- upwards
- referrals when <command>additional-from-cache no</command>
- has been specified. Instead, it will respond to such
- queries
- with REFUSED. This should not cause any problems since
- upwards referrals are not required for the resolution
- process.
- </para>
-
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>match-mapped-addresses</command></term>
- <listitem>
- <para>
- If <userinput>yes</userinput>, then an
- IPv4-mapped IPv6 address will match any address match
- list entries that match the corresponding IPv4 address.
- </para>
- <para>
- This option was introduced to work around a kernel quirk
- in some operating systems that causes IPv4 TCP
- connections, such as zone transfers, to be accepted on an
- IPv6 socket using mapped addresses. This caused address
- match lists designed for IPv4 to fail to match. However,
- <command>named</command> now solves this problem
- internally. The use of this option is discouraged.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>filter-aaaa-on-v4</command></term>
- <listitem>
- <para>
- This option is only available when
- <acronym>BIND</acronym> 9 is compiled with the
- <userinput>--enable-filter-aaaa</userinput> option on the
- "configure" command line. It is intended to help the
- transition from IPv4 to IPv6 by not giving IPv6 addresses
- to DNS clients unless they have connections to the IPv6
- Internet. This is not recommended unless absolutely
- necessary. The default is <userinput>no</userinput>.
- The <command>filter-aaaa-on-v4</command> option
- may also be specified in <command>view</command> statements
- to override the global <command>filter-aaaa-on-v4</command>
- option.
- </para>
- <para>
- If <userinput>yes</userinput>,
- the DNS client is at an IPv4 address, in <command>filter-aaaa</command>,
- and if the response does not include DNSSEC signatures,
- then all AAAA records are deleted from the response.
- This filtering applies to all responses and not only
- authoritative responses.
- </para>
- <para>
- If <userinput>break-dnssec</userinput>,
- then AAAA records are deleted even when DNSSEC is enabled.
- As suggested by the name, this makes the response not verify,
- because the DNSSEC protocol is designed detect deletions.
- </para>
- <para>
- This mechanism can erroneously cause other servers to
- not give AAAA records to their clients.
- A recursing server with both IPv6 and IPv4 network connections
- that queries an authoritative server using this mechanism
- via IPv4 will be denied AAAA records even if its client is
- using IPv6.
- </para>
- <para>
- This mechanism is applied to authoritative as well as
- non-authoritative records.
- A client using IPv4 that is not allowed recursion can
- erroneously be given AAAA records because the server is not
- allowed to check for A records.
- </para>
- <para>
- Some AAAA records are given to IPv4 clients in glue records.
- IPv4 clients that are servers can then erroneously
- answer requests for AAAA records received via IPv4.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>filter-aaaa-on-v6</command></term>
- <listitem>
- <para>
- Identical to <command>filter-aaaa-on-v4</command>,
- except it filters AAAA responses to queries from IPv6
- clients instead of IPv4 clients. To filter all
- responses, set both options to <userinput>yes</userinput>.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>ixfr-from-differences</command></term>
- <listitem>
- <para>
- When <userinput>yes</userinput> and the server loads a new
- version of a master zone from its zone file or receives a
- new version of a slave file via zone transfer, it will
- compare the new version to the previous one and calculate
- a set of differences. The differences are then logged in
- the zone's journal file such that the changes can be
- transmitted to downstream slaves as an incremental zone
- transfer.
- </para>
- <para>
- By allowing incremental zone transfers to be used for
- non-dynamic zones, this option saves bandwidth at the
- expense of increased CPU and memory consumption at the
- master.
- In particular, if the new version of a zone is completely
- different from the previous one, the set of differences
- will be of a size comparable to the combined size of the
- old and new zone version, and the server will need to
- temporarily allocate memory to hold this complete
- difference set.
- </para>
- <para><command>ixfr-from-differences</command>
- also accepts <command>master</command> and
- <command>slave</command> at the view and options
- levels which causes
- <command>ixfr-from-differences</command> to be enabled for
- all <command>master</command> or
- <command>slave</command> zones respectively.
- It is off by default.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>multi-master</command></term>
- <listitem>
- <para>
- This should be set when you have multiple masters for a zone
- and the
- addresses refer to different machines. If <userinput>yes</userinput>, <command>named</command> will
- not log
- when the serial number on the master is less than what <command>named</command>
- currently
- has. The default is <userinput>no</userinput>.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>dnssec-enable</command></term>
- <listitem>
- <para>
- Enable DNSSEC support in <command>named</command>. Unless set to <userinput>yes</userinput>,
- <command>named</command> behaves as if it does not support DNSSEC.
- The default is <userinput>yes</userinput>.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>dnssec-validation</command></term>
- <listitem>
- <para>
- Enable DNSSEC validation in <command>named</command>.
- Note <command>dnssec-enable</command> also needs to be
- set to <userinput>yes</userinput> to be effective.
- If set to <userinput>no</userinput>, DNSSEC validation
- is disabled. If set to <userinput>auto</userinput>,
- DNSSEC validation is enabled, and a default
- trust-anchor for the DNS root zone is used. If set to
- <userinput>yes</userinput>, DNSSEC validation is enabled,
- but a trust anchor must be manually configured using
- a <command>trusted-keys</command> or
- <command>managed-keys</command> statement. The default
- is <userinput>yes</userinput>.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>dnssec-accept-expired</command></term>
- <listitem>
- <para>
- Accept expired signatures when verifying DNSSEC signatures.
- The default is <userinput>no</userinput>.
- Setting this option to <userinput>yes</userinput>
- leaves <command>named</command> vulnerable to
- replay attacks.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>querylog</command></term>
- <listitem>
- <para>
- Specify whether query logging should be started when <command>named</command>
- starts.
- If <command>querylog</command> is not specified,
- then the query logging
- is determined by the presence of the logging category <command>queries</command>.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>check-names</command></term>
- <listitem>
- <para>
- This option is used to restrict the character set and syntax
- of
- certain domain names in master files and/or DNS responses
- received
- from the network. The default varies according to usage
- area. For
- <command>master</command> zones the default is <command>fail</command>.
- For <command>slave</command> zones the default
- is <command>warn</command>.
- For answers received from the network (<command>response</command>)
- the default is <command>ignore</command>.
- </para>
- <para>
- The rules for legal hostnames and mail domains are derived
- from RFC 952 and RFC 821 as modified by RFC 1123.
- </para>
- <para><command>check-names</command>
- applies to the owner names of A, AAAA and MX records.
- It also applies to the domain names in the RDATA of NS, SOA,
- MX, and SRV records.
- It also applies to the RDATA of PTR records where the owner
- name indicated that it is a reverse lookup of a hostname
- (the owner name ends in IN-ADDR.ARPA, IP6.ARPA, or IP6.INT).
- </para>
- </listitem>
- </varlistentry>
+ <varlistentry>
+ <term><command>zone-statistics</command></term>
+ <listitem>
+ <para>
+ If <userinput>full</userinput>, the server will collect
+ statistical data on all zones (unless specifically
+ turned off on a per-zone basis by specifying
+ <command>zone-statistics terse</command> or
+ <command>zone-statistics none</command>
+ in the <command>zone</command> statement).
+ The default is <userinput>terse</userinput>, providing
+ minimal statistics on zones (including name and
+ current serial number, but not query type
+ counters).
+ </para>
+ <para>
+ These statistics may be accessed via the
+ <command>statistics-channel</command> or
+ using <command>rndc stats</command>, which
+ will dump them to the file listed
+ in the <command>statistics-file</command>. See
+ also <xref linkend="statsfile"/>.
+ </para>
+ <para>
+ For backward compatibility with earlier versions
+ of BIND 9, the <command>zone-statistics</command>
+ option can also accept <userinput>yes</userinput>
+ or <userinput>no</userinput>; <userinput>yes</userinput>
+ has the same meaning as <userinput>full</userinput>.
+ As of <acronym>BIND</acronym> 9.10,
+ <userinput>no</userinput> has the same meaning
+ as <userinput>none</userinput>; previously, it
+ was the same as <userinput>terse</userinput>.
+ </para>
+ </listitem>
+ </varlistentry>
+ </variablelist>
+
+ <sect3 id="boolean_options">
+ <title>Boolean Options</title>
+
+ <variablelist>
<varlistentry>
- <term><command>check-dup-records</command></term>
+ <term><command>allow-new-zones</command></term>
<listitem>
<para>
- Check master zones for records that are treated as different
- by DNSSEC but are semantically equal in plain DNS. The
- default is to <command>warn</command>. Other possible
- values are <command>fail</command> and
- <command>ignore</command>.
+ If <userinput>yes</userinput>, then zones can be
+ added at runtime via <command>rndc addzone</command>
+ or deleted via <command>rndc delzone</command>.
+ The default is <userinput>no</userinput>.
</para>
</listitem>
</varlistentry>
<varlistentry>
- <term><command>check-mx</command></term>
+ <term><command>auth-nxdomain</command></term>
<listitem>
<para>
- Check whether the MX record appears to refer to a IP address.
- The default is to <command>warn</command>. Other possible
- values are <command>fail</command> and
- <command>ignore</command>.
+ If <userinput>yes</userinput>, then the <command>AA</command> bit
+ is always set on NXDOMAIN responses, even if the server is
+ not actually
+ authoritative. The default is <userinput>no</userinput>;
+ this is
+ a change from <acronym>BIND</acronym> 8. If you
+ are using very old DNS software, you
+ may need to set it to <userinput>yes</userinput>.
</para>
</listitem>
</varlistentry>
- <varlistentry>
- <term><command>check-wildcard</command></term>
- <listitem>
- <para>
- This option is used to check for non-terminal wildcards.
- The use of non-terminal wildcards is almost always as a
- result of a failure
- to understand the wildcard matching algorithm (RFC 1034).
- This option
- affects master zones. The default (<command>yes</command>) is to check
- for non-terminal wildcards and issue a warning.
- </para>
- </listitem>
- </varlistentry>
+ <varlistentry>
+ <term><command>deallocate-on-exit</command></term>
+ <listitem>
+ <para>
+ This option was used in <acronym>BIND</acronym>
+ 8 to enable checking
+ for memory leaks on exit. <acronym>BIND</acronym> 9 ignores the option and always performs
+ the checks.
+ </para>
+ </listitem>
+ </varlistentry>
<varlistentry>
- <term><command>check-integrity</command></term>
+ <term><command>memstatistics</command></term>
<listitem>
<para>
- Perform post load zone integrity checks on master
- zones. This checks that MX and SRV records refer
- to address (A or AAAA) records and that glue
- address records exist for delegated zones. For
- MX and SRV records only in-zone hostnames are
- checked (for out-of-zone hostnames use
- <command>named-checkzone</command>).
- For NS records only names below top of zone are
- checked (for out-of-zone names and glue consistency
- checks use <command>named-checkzone</command>).
- The default is <command>yes</command>.
+ Write memory statistics to the file specified by
+ <command>memstatistics-file</command> at exit.
+ The default is <userinput>no</userinput> unless
+ '-m record' is specified on the command line in
+ which case it is <userinput>yes</userinput>.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>dialup</command></term>
+ <listitem>
+ <para>
+ If <userinput>yes</userinput>, then the
+ server treats all zones as if they are doing zone transfers
+ across
+ a dial-on-demand dialup link, which can be brought up by
+ traffic
+ originating from this server. This has different effects
+ according
+ to zone type and concentrates the zone maintenance so that
+ it all
+ happens in a short interval, once every <command>heartbeat-interval</command> and
+ hopefully during the one call. It also suppresses some of
+ the normal
+ zone maintenance traffic. The default is <userinput>no</userinput>.
</para>
<para>
- Check that the two forms of Sender Policy Framework
- records (TXT records starting with "v=spf1" and SPF) either
- both exist or both don't exist. Warnings are
- emitted it they don't and be suppressed with
- <command>check-spf</command>.
+ The <command>dialup</command> option
+ may also be specified in the <command>view</command> and
+ <command>zone</command> statements,
+ in which case it overrides the global <command>dialup</command>
+ option.
+ </para>
+ <para>
+ If the zone is a master zone, then the server will send out a
+ NOTIFY
+ request to all the slaves (default). This should trigger the
+ zone serial
+ number check in the slave (providing it supports NOTIFY)
+ allowing the slave
+ to verify the zone while the connection is active.
+ The set of servers to which NOTIFY is sent can be controlled
+ by
+ <command>notify</command> and <command>also-notify</command>.
+ </para>
+ <para>
+ If the
+ zone is a slave or stub zone, then the server will suppress
+ the regular
+ "zone up to date" (refresh) queries and only perform them
+ when the
+ <command>heartbeat-interval</command> expires in
+ addition to sending
+ NOTIFY requests.
+ </para>
+ <para>
+ Finer control can be achieved by using
+ <userinput>notify</userinput> which only sends NOTIFY
+ messages,
+ <userinput>notify-passive</userinput> which sends NOTIFY
+ messages and
+ suppresses the normal refresh queries, <userinput>refresh</userinput>
+ which suppresses normal refresh processing and sends refresh
+ queries
+ when the <command>heartbeat-interval</command>
+ expires, and
+ <userinput>passive</userinput> which just disables normal
+ refresh
+ processing.
</para>
+
+ <informaltable colsep="0" rowsep="0">
+ <tgroup cols="4" colsep="0" rowsep="0" tgroupstyle="4Level-table">
+ <colspec colname="1" colnum="1" colsep="0" colwidth="1.150in"/>
+ <colspec colname="2" colnum="2" colsep="0" colwidth="1.150in"/>
+ <colspec colname="3" colnum="3" colsep="0" colwidth="1.150in"/>
+ <colspec colname="4" colnum="4" colsep="0" colwidth="1.150in"/>
+ <tbody>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ dialup mode
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ normal refresh
+ </para>
+ </entry>
+ <entry colname="3">
+ <para>
+ heart-beat refresh
+ </para>
+ </entry>
+ <entry colname="4">
+ <para>
+ heart-beat notify
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para><command>no</command> (default)</para>
+ </entry>
+ <entry colname="2">
+ <para>
+ yes
+ </para>
+ </entry>
+ <entry colname="3">
+ <para>
+ no
+ </para>
+ </entry>
+ <entry colname="4">
+ <para>
+ no
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para><command>yes</command></para>
+ </entry>
+ <entry colname="2">
+ <para>
+ no
+ </para>
+ </entry>
+ <entry colname="3">
+ <para>
+ yes
+ </para>
+ </entry>
+ <entry colname="4">
+ <para>
+ yes
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para><command>notify</command></para>
+ </entry>
+ <entry colname="2">
+ <para>
+ yes
+ </para>
+ </entry>
+ <entry colname="3">
+ <para>
+ no
+ </para>
+ </entry>
+ <entry colname="4">
+ <para>
+ yes
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para><command>refresh</command></para>
+ </entry>
+ <entry colname="2">
+ <para>
+ no
+ </para>
+ </entry>
+ <entry colname="3">
+ <para>
+ yes
+ </para>
+ </entry>
+ <entry colname="4">
+ <para>
+ no
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para><command>passive</command></para>
+ </entry>
+ <entry colname="2">
+ <para>
+ no
+ </para>
+ </entry>
+ <entry colname="3">
+ <para>
+ no
+ </para>
+ </entry>
+ <entry colname="4">
+ <para>
+ no
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para><command>notify-passive</command></para>
+ </entry>
+ <entry colname="2">
+ <para>
+ no
+ </para>
+ </entry>
+ <entry colname="3">
+ <para>
+ no
+ </para>
+ </entry>
+ <entry colname="4">
+ <para>
+ yes
+ </para>
+ </entry>
+ </row>
+ </tbody>
+ </tgroup>
+ </informaltable>
+
+ <para>
+ Note that normal NOTIFY processing is not affected by
+ <command>dialup</command>.
+ </para>
+
</listitem>
</varlistentry>
<varlistentry>
- <term><command>check-mx-cname</command></term>
+ <term><command>fake-iquery</command></term>
<listitem>
<para>
- If <command>check-integrity</command> is set then
- fail, warn or ignore MX records that refer
- to CNAMES. The default is to <command>warn</command>.
+ In <acronym>BIND</acronym> 8, this option
+ enabled simulating the obsolete DNS query type
+ IQUERY. <acronym>BIND</acronym> 9 never does
+ IQUERY simulation.
</para>
</listitem>
</varlistentry>
<varlistentry>
- <term><command>check-srv-cname</command></term>
+ <term><command>fetch-glue</command></term>
<listitem>
<para>
- If <command>check-integrity</command> is set then
- fail, warn or ignore SRV records that refer
- to CNAMES. The default is to <command>warn</command>.
+ This option is obsolete.
+ In BIND 8, <userinput>fetch-glue yes</userinput>
+ caused the server to attempt to fetch glue resource records
+ it
+ didn't have when constructing the additional
+ data section of a response. This is now considered a bad
+ idea
+ and BIND 9 never does it.
</para>
</listitem>
</varlistentry>
<varlistentry>
- <term><command>check-sibling</command></term>
+ <term><command>flush-zones-on-shutdown</command></term>
<listitem>
<para>
- When performing integrity checks, also check that
- sibling glue exists. The default is <command>yes</command>.
+ When the nameserver exits due receiving SIGTERM,
+ flush or do not flush any pending zone writes. The default
+ is
+ <command>flush-zones-on-shutdown</command> <userinput>no</userinput>.
</para>
</listitem>
</varlistentry>
<varlistentry>
- <term><command>check-spf</command></term>
+ <term><command>has-old-clients</command></term>
<listitem>
<para>
- When performing integrity checks, check that the
- two forms of Sender Policy Framwork records (TXT
- records starting with "v=spf1" and SPF) both exist
- or both don't exist and issue a warning if not
- met. The default is <command>warn</command>.
+ This option was incorrectly implemented
+ in <acronym>BIND</acronym> 8, and is ignored by <acronym>BIND</acronym> 9.
+ To achieve the intended effect
+ of
+ <command>has-old-clients</command> <userinput>yes</userinput>, specify
+ the two separate options <command>auth-nxdomain</command> <userinput>yes</userinput>
+ and <command>rfc2308-type1</command> <userinput>no</userinput> instead.
</para>
</listitem>
</varlistentry>
<varlistentry>
- <term><command>zero-no-soa-ttl</command></term>
+ <term><command>host-statistics</command></term>
<listitem>
- <para>
- When returning authoritative negative responses to
- SOA queries set the TTL of the SOA record returned in
- the authority section to zero.
- The default is <command>yes</command>.
- </para>
+ <para>
+ In BIND 8, this enables keeping of
+ statistics for every host that the name server interacts
+ with.
+ Not implemented in BIND 9.
+ </para>
</listitem>
</varlistentry>
<varlistentry>
- <term><command>zero-no-soa-ttl-cache</command></term>
+ <term><command>maintain-ixfr-base</command></term>
<listitem>
- <para>
- When caching a negative response to a SOA query
- set the TTL to zero.
- The default is <command>no</command>.
- </para>
+ <para>
+ <emphasis>This option is obsolete</emphasis>.
+ It was used in <acronym>BIND</acronym> 8 to
+ determine whether a transaction log was
+ kept for Incremental Zone Transfer. <acronym>BIND</acronym> 9 maintains a transaction
+ log whenever possible. If you need to disable outgoing
+ incremental zone
+ transfers, use <command>provide-ixfr</command> <userinput>no</userinput>.
+ </para>
</listitem>
</varlistentry>
<varlistentry>
- <term><command>update-check-ksk</command></term>
+ <term><command>minimal-responses</command></term>
<listitem>
- <para>
- When set to the default value of <literal>yes</literal>,
- check the KSK bit in each key to determine how the key
- should be used when generating RRSIGs for a secure zone.
- </para>
- <para>
- Ordinarily, zone-signing keys (that is, keys without the
- KSK bit set) are used to sign the entire zone, while
- key-signing keys (keys with the KSK bit set) are only
- used to sign the DNSKEY RRset at the zone apex.
- However, if this option is set to <literal>no</literal>,
- then the KSK bit is ignored; KSKs are treated as if they
- were ZSKs and are used to sign the entire zone. This is
- similar to the <command>dnssec-signzone -z</command>
- command line option.
- </para>
- <para>
- When this option is set to <literal>yes</literal>, there
- must be at least two active keys for every algorithm
- represented in the DNSKEY RRset: at least one KSK and one
- ZSK per algorithm. If there is any algorithm for which
- this requirement is not met, this option will be ignored
- for that algorithm.
+ <para>
+ If <userinput>yes</userinput>, then when generating
+ responses the server will only add records to the authority
+ and additional data sections when they are required (e.g.
+ delegations, negative responses). This may improve the
+ performance of the server.
+ The default is <userinput>no</userinput>.
</para>
</listitem>
</varlistentry>
<varlistentry>
- <term><command>dnssec-dnskey-kskonly</command></term>
+ <term><command>multiple-cnames</command></term>
<listitem>
- <para>
- When this option and <command>update-check-ksk</command>
- are both set to <literal>yes</literal>, only key-signing
- keys (that is, keys with the KSK bit set) will be used
- to sign the DNSKEY RRset at the zone apex. Zone-signing
- keys (keys without the KSK bit set) will be used to sign
- the remainder of the zone, but not the DNSKEY RRset.
- This is similar to the
- <command>dnssec-signzone -x</command> command line option.
- </para>
<para>
- The default is <command>no</command>. If
- <command>update-check-ksk</command> is set to
- <literal>no</literal>, this option is ignored.
+ This option was used in <acronym>BIND</acronym> 8 to allow
+ a domain name to have multiple CNAME records in violation of
+ the DNS standards. <acronym>BIND</acronym> 9.2 onwards
+ always strictly enforces the CNAME rules both in master
+ files and dynamic updates.
</para>
</listitem>
</varlistentry>
<varlistentry>
- <term><command>dnssec-loadkeys-interval</command></term>
+ <term><command>notify</command></term>
<listitem>
- <para>
- When a zone is configured with <command>auto-dnssec
- maintain;</command> its key repository must be checked
- periodically to see if any new keys have been added
- or any existing keys' timing metadata has been updated
- (see <xref linkend="man.dnssec-keygen"/> and
- <xref linkend="man.dnssec-settime"/>). The
- <command>dnssec-loadkeys-interval</command> option
- sets the frequency of automatic repository checks, in
- minutes. The default is <literal>60</literal> (1 hour),
- the minimum is <literal>1</literal> (1 minute), and the
- maximum is <literal>1440</literal> (24 hours); any higher
- value is silently reduced.
+ <para>
+ If <userinput>yes</userinput> (the default),
+ DNS NOTIFY messages are sent when a zone the server is
+ authoritative for
+ changes, see <xref linkend="notify"/>. The messages are
+ sent to the
+ servers listed in the zone's NS records (except the master
+ server identified
+ in the SOA MNAME field), and to any servers listed in the
+ <command>also-notify</command> option.
+ </para>
+ <para>
+ If <userinput>master-only</userinput>, notifies are only
+ sent
+ for master zones.
+ If <userinput>explicit</userinput>, notifies are sent only
+ to
+ servers explicitly listed using <command>also-notify</command>.
+ If <userinput>no</userinput>, no notifies are sent.
+ </para>
+ <para>
+ The <command>notify</command> option may also be
+ specified in the <command>zone</command>
+ statement,
+ in which case it overrides the <command>options notify</command> statement.
+ It would only be necessary to turn off this option if it
+ caused slaves
+ to crash.
</para>
</listitem>
</varlistentry>
<varlistentry>
- <term><command>try-tcp-refresh</command></term>
+ <term><command>notify-to-soa</command></term>
<listitem>
- <para>
- Try to refresh the zone using TCP if UDP queries fail.
- For BIND 8 compatibility, the default is
- <command>yes</command>.
+ <para>
+ If <userinput>yes</userinput> do not check the nameservers
+ in the NS RRset against the SOA MNAME. Normally a NOTIFY
+ message is not sent to the SOA MNAME (SOA ORIGIN) as it is
+ supposed to contain the name of the ultimate master.
+ Sometimes, however, a slave is listed as the SOA MNAME in
+ hidden master configurations and in that case you would
+ want the ultimate master to still send NOTIFY messages to
+ all the nameservers listed in the NS RRset.
</para>
</listitem>
</varlistentry>
<varlistentry>
- <term><command>dnssec-secure-to-insecure</command></term>
+ <term><command>recursion</command></term>
<listitem>
- <para>
- Allow a dynamic zone to transition from secure to
- insecure (i.e., signed to unsigned) by deleting all
- of the DNSKEY records. The default is <command>no</command>.
- If set to <command>yes</command>, and if the DNSKEY RRset
- at the zone apex is deleted, all RRSIG and NSEC records
- will be removed from the zone as well.
- </para>
- <para>
- If the zone uses NSEC3, then it is also necessary to
- delete the NSEC3PARAM RRset from the zone apex; this will
- cause the removal of all corresponding NSEC3 records.
- (It is expected that this requirement will be eliminated
- in a future release.)
- </para>
- <para>
- Note that if a zone has been configured with
- <command>auto-dnssec maintain</command> and the
- private keys remain accessible in the key repository,
- then the zone will be automatically signed again the
- next time <command>named</command> is started.
+ <para>
+ If <userinput>yes</userinput>, and a
+ DNS query requests recursion, then the server will attempt
+ to do
+ all the work required to answer the query. If recursion is
+ off
+ and the server does not already know the answer, it will
+ return a
+ referral response. The default is
+ <userinput>yes</userinput>.
+ Note that setting <command>recursion no</command> does not prevent
+ clients from getting data from the server's cache; it only
+ prevents new data from being cached as an effect of client
+ queries.
+ Caching may still occur as an effect the server's internal
+ operation, such as NOTIFY address lookups.
+ See also <command>fetch-glue</command> above.
</para>
</listitem>
</varlistentry>
- </variablelist>
-
- </sect3>
-
- <sect3>
- <title>Forwarding</title>
- <para>
- The forwarding facility can be used to create a large site-wide
- cache on a few servers, reducing traffic over links to external
- name servers. It can also be used to allow queries by servers that
- do not have direct access to the Internet, but wish to look up
- exterior
- names anyway. Forwarding occurs only on those queries for which
- the server is not authoritative and does not have the answer in
- its cache.
- </para>
-
- <variablelist>
- <varlistentry>
- <term><command>forward</command></term>
- <listitem>
- <para>
- This option is only meaningful if the
- forwarders list is not empty. A value of <varname>first</varname>,
- the default, causes the server to query the forwarders
- first — and
- if that doesn't answer the question, the server will then
- look for
- the answer itself. If <varname>only</varname> is
- specified, the
- server will only query the forwarders.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>forwarders</command></term>
- <listitem>
- <para>
- Specifies the IP addresses to be used
- for forwarding. The default is the empty list (no
- forwarding).
- </para>
- </listitem>
- </varlistentry>
-
- </variablelist>
-
- <para>
- Forwarding can also be configured on a per-domain basis, allowing
- for the global forwarding options to be overridden in a variety
- of ways. You can set particular domains to use different
- forwarders,
- or have a different <command>forward only/first</command> behavior,
- or not forward at all, see <xref linkend="zone_statement_grammar"/>.
- </para>
- </sect3>
-
- <sect3>
- <title>Dual-stack Servers</title>
- <para>
- Dual-stack servers are used as servers of last resort to work
- around
- problems in reachability due the lack of support for either IPv4
- or IPv6
- on the host machine.
- </para>
-
- <variablelist>
- <varlistentry>
- <term><command>dual-stack-servers</command></term>
- <listitem>
- <para>
- Specifies host names or addresses of machines with access to
- both IPv4 and IPv6 transports. If a hostname is used, the
- server must be able
- to resolve the name using only the transport it has. If the
- machine is dual
- stacked, then the <command>dual-stack-servers</command> have no effect unless
- access to a transport has been disabled on the command line
- (e.g. <command>named -4</command>).
- </para>
- </listitem>
- </varlistentry>
- </variablelist>
- </sect3>
-
- <sect3 id="access_control">
- <title>Access Control</title>
-
- <para>
- Access to the server can be restricted based on the IP address
- of the requesting system. See <xref linkend="address_match_lists"/> for
- details on how to specify IP address lists.
- </para>
-
- <variablelist>
-
- <varlistentry>
- <term><command>allow-notify</command></term>
- <listitem>
- <para>
- Specifies which hosts are allowed to
- notify this server, a slave, of zone changes in addition
- to the zone masters.
- <command>allow-notify</command> may also be
- specified in the
- <command>zone</command> statement, in which case
- it overrides the
- <command>options allow-notify</command>
- statement. It is only meaningful
- for a slave zone. If not specified, the default is to
- process notify messages
- only from a zone's master.
- </para>
- </listitem>
- </varlistentry>
+ <varlistentry>
+ <term><command>request-nsid</command></term>
+ <listitem>
+ <para>
+ If <userinput>yes</userinput>, then an empty EDNS(0)
+ NSID (Name Server Identifier) option is sent with all
+ queries to authoritative name servers during iterative
+ resolution. If the authoritative server returns an NSID
+ option in its response, then its contents are logged in
+ the <command>resolver</command> category at level
+ <command>info</command>.
+ The default is <userinput>no</userinput>.
+ </para>
+ </listitem>
+ </varlistentry>
<varlistentry>
- <term><command>allow-query</command></term>
+ <term><command>rfc2308-type1</command></term>
<listitem>
<para>
- Specifies which hosts are allowed to ask ordinary
- DNS questions. <command>allow-query</command> may
- also be specified in the <command>zone</command>
- statement, in which case it overrides the
- <command>options allow-query</command> statement.
- If not specified, the default is to allow queries
- from all hosts.
+ Setting this to <userinput>yes</userinput> will
+ cause the server to send NS records along with the SOA
+ record for negative
+ answers. The default is <userinput>no</userinput>.
</para>
<note>
- <para>
- <command>allow-query-cache</command> is now
- used to specify access to the cache.
- </para>
+ <simpara>
+ Not yet implemented in <acronym>BIND</acronym>
+ 9.
+ </simpara>
</note>
</listitem>
</varlistentry>
<varlistentry>
- <term><command>allow-query-on</command></term>
+ <term><command>use-id-pool</command></term>
<listitem>
<para>
- Specifies which local addresses can accept ordinary
- DNS questions. This makes it possible, for instance,
- to allow queries on internal-facing interfaces but
- disallow them on external-facing ones, without
- necessarily knowing the internal network's addresses.
- </para>
- <para>
- Note that <command>allow-query-on</command> is only
- checked for queries that are permitted by
- <command>allow-query</command>. A query must be
- allowed by both ACLs, or it will be refused.
- </para>
- <para>
- <command>allow-query-on</command> may
- also be specified in the <command>zone</command>
- statement, in which case it overrides the
- <command>options allow-query-on</command> statement.
+ <emphasis>This option is obsolete</emphasis>.
+ <acronym>BIND</acronym> 9 always allocates query
+ IDs from a pool.
</para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>use-ixfr</command></term>
+ <listitem>
<para>
- If not specified, the default is to allow queries
- on all addresses.
+ <emphasis>This option is obsolete</emphasis>.
+ If you need to disable IXFR to a particular server or
+ servers, see
+ the information on the <command>provide-ixfr</command> option
+ in <xref linkend="server_statement_definition_and_usage"/>.
+ See also
+ <xref linkend="incremental_zone_transfers"/>.
</para>
- <note>
- <para>
- <command>allow-query-cache</command> is
- used to specify access to the cache.
- </para>
- </note>
</listitem>
</varlistentry>
<varlistentry>
- <term><command>allow-query-cache</command></term>
+ <term><command>provide-ixfr</command></term>
<listitem>
<para>
- Specifies which hosts are allowed to get answers
- from the cache. If <command>allow-query-cache</command>
- is not set then <command>allow-recursion</command>
- is used if set, otherwise <command>allow-query</command>
- is used if set unless <command>recursion no;</command> is
- set in which case <command>none;</command> is used,
- otherwise the default (<command>localnets;</command>
- <command>localhost;</command>) is used.
+ See the description of
+ <command>provide-ixfr</command> in
+ <xref linkend="server_statement_definition_and_usage"/>.
</para>
</listitem>
</varlistentry>
<varlistentry>
- <term><command>allow-query-cache-on</command></term>
+ <term><command>request-ixfr</command></term>
<listitem>
<para>
- Specifies which local addresses can give answers
- from the cache. If not specified, the default is
- to allow cache queries on any address,
- <command>localnets</command> and
- <command>localhost</command>.
+ See the description of
+ <command>request-ixfr</command> in
+ <xref linkend="server_statement_definition_and_usage"/>.
</para>
</listitem>
</varlistentry>
- <varlistentry>
- <term><command>allow-recursion</command></term>
- <listitem>
+ <varlistentry>
+ <term><command>treat-cr-as-space</command></term>
+ <listitem>
<para>
- Specifies which hosts are allowed to make recursive
- queries through this server. If
- <command>allow-recursion</command> is not set
- then <command>allow-query-cache</command> is
- used if set, otherwise <command>allow-query</command>
- is used if set, otherwise the default
- (<command>localnets;</command>
- <command>localhost;</command>) is used.
+ This option was used in <acronym>BIND</acronym>
+ 8 to make
+ the server treat carriage return ("<command>\r</command>") characters the same way
+ as a space or tab character,
+ to facilitate loading of zone files on a UNIX system that
+ were generated
+ on an NT or DOS machine. In <acronym>BIND</acronym> 9, both UNIX "<command>\n</command>"
+ and NT/DOS "<command>\r\n</command>" newlines
+ are always accepted,
+ and the option is ignored.
</para>
- </listitem>
- </varlistentry>
+ </listitem>
+ </varlistentry>
- <varlistentry>
- <term><command>allow-recursion-on</command></term>
- <listitem>
- <para>
- Specifies which local addresses can accept recursive
- queries. If not specified, the default is to allow
- recursive queries on all addresses.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>allow-update</command></term>
- <listitem>
- <para>
- Specifies which hosts are allowed to
- submit Dynamic DNS updates for master zones. The default is
- to deny
- updates from all hosts. Note that allowing updates based
- on the requestor's IP address is insecure; see
- <xref linkend="dynamic_update_security"/> for details.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>allow-update-forwarding</command></term>
- <listitem>
- <para>
- Specifies which hosts are allowed to
- submit Dynamic DNS updates to slave zones to be forwarded to
- the
- master. The default is <userinput>{ none; }</userinput>,
- which
- means that no update forwarding will be performed. To
- enable
- update forwarding, specify
- <userinput>allow-update-forwarding { any; };</userinput>.
- Specifying values other than <userinput>{ none; }</userinput> or
- <userinput>{ any; }</userinput> is usually
- counterproductive, since
- the responsibility for update access control should rest
- with the
- master server, not the slaves.
- </para>
- <para>
- Note that enabling the update forwarding feature on a slave
- server
- may expose master servers relying on insecure IP address
- based
- access control to attacks; see <xref linkend="dynamic_update_security"/>
- for more details.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>allow-v6-synthesis</command></term>
- <listitem>
- <para>
- This option was introduced for the smooth transition from
- AAAA
- to A6 and from "nibble labels" to binary labels.
- However, since both A6 and binary labels were then
- deprecated,
- this option was also deprecated.
- It is now ignored with some warning messages.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>allow-transfer</command></term>
- <listitem>
- <para>
- Specifies which hosts are allowed to
- receive zone transfers from the server. <command>allow-transfer</command> may
- also be specified in the <command>zone</command>
- statement, in which
- case it overrides the <command>options allow-transfer</command> statement.
- If not specified, the default is to allow transfers to all
- hosts.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>blackhole</command></term>
- <listitem>
- <para>
- Specifies a list of addresses that the
- server will not accept queries from or use to resolve a
- query. Queries
- from these addresses will not be responded to. The default
- is <userinput>none</userinput>.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>filter-aaaa</command></term>
- <listitem>
- <para>
- Specifies a list of addresses to which
- <command>filter-aaaa-on-v4</command>
- is applies. The default is <userinput>any</userinput>.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>resolver-query-timeout</command></term>
- <listitem>
- <para>
- The amount of time the resolver will spend attempting
- to resolve a recursive query before failing. The default
- and minimum is <literal>10</literal> and the maximum is
- <literal>30</literal>. Setting it to <literal>0</literal>
- will result in the default being used.
- </para>
- </listitem>
- </varlistentry>
- </variablelist>
-
- </sect3>
-
- <sect3>
- <title>Interfaces</title>
- <para>
- The interfaces and ports that the server will answer queries
- from may be specified using the <command>listen-on</command> option. <command>listen-on</command> takes
- an optional port and an <varname>address_match_list</varname>.
- The server will listen on all interfaces allowed by the address
- match list. If a port is not specified, port 53 will be used.
- </para>
- <para>
- Multiple <command>listen-on</command> statements are
- allowed.
- For example,
- </para>
+ <varlistentry>
+ <term><command>additional-from-auth</command></term>
+ <term><command>additional-from-cache</command></term>
+ <listitem>
-<programlisting>listen-on { 5.6.7.8; };
-listen-on port 1234 { !1.2.3.4; 1.2/16; };
-</programlisting>
+ <para>
+ These options control the behavior of an authoritative
+ server when
+ answering queries which have additional data, or when
+ following CNAME
+ and DNAME chains.
+ </para>
- <para>
- will enable the name server on port 53 for the IP address
- 5.6.7.8, and on port 1234 of an address on the machine in net
- 1.2 that is not 1.2.3.4.
- </para>
-
- <para>
- If no <command>listen-on</command> is specified, the
- server will listen on port 53 on all IPv4 interfaces.
- </para>
-
- <para>
- The <command>listen-on-v6</command> option is used to
- specify the interfaces and the ports on which the server will
- listen for incoming queries sent using IPv6. If not specified,
- the server will listen on port 53 on all IPv6 interfaces.
- </para>
-
- <para>
- When <programlisting>{ any; }</programlisting> is
- specified
- as the <varname>address_match_list</varname> for the
- <command>listen-on-v6</command> option,
- the server does not bind a separate socket to each IPv6 interface
- address as it does for IPv4 if the operating system has enough API
- support for IPv6 (specifically if it conforms to RFC 3493 and RFC
- 3542).
- Instead, it listens on the IPv6 wildcard address.
- If the system only has incomplete API support for IPv6, however,
- the behavior is the same as that for IPv4.
- </para>
-
- <para>
- A list of particular IPv6 addresses can also be specified, in
- which case
- the server listens on a separate socket for each specified
- address,
- regardless of whether the desired API is supported by the system.
- </para>
-
- <para>
- Multiple <command>listen-on-v6</command> options can
- be used.
- For example,
- </para>
+ <para>
+ When both of these options are set to <userinput>yes</userinput>
+ (the default) and a
+ query is being answered from authoritative data (a zone
+ configured into the server), the additional data section of
+ the
+ reply will be filled in using data from other authoritative
+ zones
+ and from the cache. In some situations this is undesirable,
+ such
+ as when there is concern over the correctness of the cache,
+ or
+ in servers where slave zones may be added and modified by
+ untrusted third parties. Also, avoiding
+ the search for this additional data will speed up server
+ operations
+ at the possible expense of additional queries to resolve
+ what would
+ otherwise be provided in the additional section.
+ </para>
-<programlisting>listen-on-v6 { any; };
-listen-on-v6 port 1234 { !2001:db8::/32; any; };
-</programlisting>
+ <para>
+ For example, if a query asks for an MX record for host <literal>foo.example.com</literal>,
+ and the record found is "<literal>MX 10 mail.example.net</literal>", normally the address
+ records (A and AAAA) for <literal>mail.example.net</literal> will be provided as well,
+ if known, even though they are not in the example.com zone.
+ Setting these options to <command>no</command>
+ disables this behavior and makes
+ the server only search for additional data in the zone it
+ answers from.
+ </para>
- <para>
- will enable the name server on port 53 for any IPv6 addresses
- (with a single wildcard socket),
- and on port 1234 of IPv6 addresses that is not in the prefix
- 2001:db8::/32 (with separate sockets for each matched address.)
- </para>
+ <para>
+ These options are intended for use in authoritative-only
+ servers, or in authoritative-only views. Attempts to set
+ them to <command>no</command> without also
+ specifying
+ <command>recursion no</command> will cause the
+ server to
+ ignore the options and log a warning message.
+ </para>
- <para>
- To make the server not listen on any IPv6 address, use
- </para>
+ <para>
+ Specifying <command>additional-from-cache no</command> actually
+ disables the use of the cache not only for additional data
+ lookups
+ but also when looking up the answer. This is usually the
+ desired
+ behavior in an authoritative-only server where the
+ correctness of
+ the cached data is an issue.
+ </para>
-<programlisting>listen-on-v6 { none; };
-</programlisting>
+ <para>
+ When a name server is non-recursively queried for a name
+ that is not
+ below the apex of any served zone, it normally answers with
+ an
+ "upwards referral" to the root servers or the servers of
+ some other
+ known parent of the query name. Since the data in an
+ upwards referral
+ comes from the cache, the server will not be able to provide
+ upwards
+ referrals when <command>additional-from-cache no</command>
+ has been specified. Instead, it will respond to such
+ queries
+ with REFUSED. This should not cause any problems since
+ upwards referrals are not required for the resolution
+ process.
+ </para>
- </sect3>
+ </listitem>
+ </varlistentry>
- <sect3 id="query_address">
- <title>Query Address</title>
- <para>
- If the server doesn't know the answer to a question, it will
- query other name servers. <command>query-source</command> specifies
- the address and port used for such queries. For queries sent over
- IPv6, there is a separate <command>query-source-v6</command> option.
- If <command>address</command> is <command>*</command> (asterisk) or is omitted,
- a wildcard IP address (<command>INADDR_ANY</command>)
- will be used.
- </para>
+ <varlistentry>
+ <term><command>match-mapped-addresses</command></term>
+ <listitem>
+ <para>
+ If <userinput>yes</userinput>, then an
+ IPv4-mapped IPv6 address will match any address match
+ list entries that match the corresponding IPv4 address.
+ </para>
+ <para>
+ This option was introduced to work around a kernel quirk
+ in some operating systems that causes IPv4 TCP
+ connections, such as zone transfers, to be accepted on an
+ IPv6 socket using mapped addresses. This caused address
+ match lists designed for IPv4 to fail to match. However,
+ <command>named</command> now solves this problem
+ internally. The use of this option is discouraged.
+ </para>
+ </listitem>
+ </varlistentry>
- <para>
- If <command>port</command> is <command>*</command> or is omitted,
- a random port number from a pre-configured
- range is picked up and will be used for each query.
- The port range(s) is that specified in
- the <command>use-v4-udp-ports</command> (for IPv4)
- and <command>use-v6-udp-ports</command> (for IPv6)
- options, excluding the ranges specified in
- the <command>avoid-v4-udp-ports</command>
- and <command>avoid-v6-udp-ports</command> options, respectively.
- </para>
+ <varlistentry>
+ <term><command>filter-aaaa-on-v4</command></term>
+ <listitem>
+ <para>
+ This option is only available when
+ <acronym>BIND</acronym> 9 is compiled with the
+ <userinput>--enable-filter-aaaa</userinput> option on the
+ "configure" command line. It is intended to help the
+ transition from IPv4 to IPv6 by not giving IPv6 addresses
+ to DNS clients unless they have connections to the IPv6
+ Internet. This is not recommended unless absolutely
+ necessary. The default is <userinput>no</userinput>.
+ The <command>filter-aaaa-on-v4</command> option
+ may also be specified in <command>view</command> statements
+ to override the global <command>filter-aaaa-on-v4</command>
+ option.
+ </para>
+ <para>
+ If <userinput>yes</userinput>,
+ the DNS client is at an IPv4 address, in <command>filter-aaaa</command>,
+ and if the response does not include DNSSEC signatures,
+ then all AAAA records are deleted from the response.
+ This filtering applies to all responses and not only
+ authoritative responses.
+ </para>
+ <para>
+ If <userinput>break-dnssec</userinput>,
+ then AAAA records are deleted even when DNSSEC is enabled.
+ As suggested by the name, this makes the response not verify,
+ because the DNSSEC protocol is designed detect deletions.
+ </para>
+ <para>
+ This mechanism can erroneously cause other servers to
+ not give AAAA records to their clients.
+ A recursing server with both IPv6 and IPv4 network connections
+ that queries an authoritative server using this mechanism
+ via IPv4 will be denied AAAA records even if its client is
+ using IPv6.
+ </para>
+ <para>
+ This mechanism is applied to authoritative as well as
+ non-authoritative records.
+ A client using IPv4 that is not allowed recursion can
+ erroneously be given AAAA records because the server is not
+ allowed to check for A records.
+ </para>
+ <para>
+ Some AAAA records are given to IPv4 clients in glue records.
+ IPv4 clients that are servers can then erroneously
+ answer requests for AAAA records received via IPv4.
+ </para>
+ </listitem>
+ </varlistentry>
- <para>
- The defaults of the <command>query-source</command> and
- <command>query-source-v6</command> options
- are:
- </para>
+ <varlistentry>
+ <term><command>filter-aaaa-on-v6</command></term>
+ <listitem>
+ <para>
+ Identical to <command>filter-aaaa-on-v4</command>,
+ except it filters AAAA responses to queries from IPv6
+ clients instead of IPv4 clients. To filter all
+ responses, set both options to <userinput>yes</userinput>.
+ </para>
+ </listitem>
+ </varlistentry>
-<programlisting>query-source address * port *;
-query-source-v6 address * port *;
-</programlisting>
-
- <para>
- If <command>use-v4-udp-ports</command> or
- <command>use-v6-udp-ports</command> is unspecified,
- <command>named</command> will check if the operating
- system provides a programming interface to retrieve the
- system's default range for ephemeral ports.
- If such an interface is available,
- <command>named</command> will use the corresponding system
- default range; otherwise, it will use its own defaults:
- </para>
+ <varlistentry>
+ <term><command>ixfr-from-differences</command></term>
+ <listitem>
+ <para>
+ When <userinput>yes</userinput> and the server loads a new
+ version of a master zone from its zone file or receives a
+ new version of a slave file via zone transfer, it will
+ compare the new version to the previous one and calculate
+ a set of differences. The differences are then logged in
+ the zone's journal file such that the changes can be
+ transmitted to downstream slaves as an incremental zone
+ transfer.
+ </para>
+ <para>
+ By allowing incremental zone transfers to be used for
+ non-dynamic zones, this option saves bandwidth at the
+ expense of increased CPU and memory consumption at the
+ master.
+ In particular, if the new version of a zone is completely
+ different from the previous one, the set of differences
+ will be of a size comparable to the combined size of the
+ old and new zone version, and the server will need to
+ temporarily allocate memory to hold this complete
+ difference set.
+ </para>
+ <para><command>ixfr-from-differences</command>
+ also accepts <command>master</command> and
+ <command>slave</command> at the view and options
+ levels which causes
+ <command>ixfr-from-differences</command> to be enabled for
+ all <command>master</command> or
+ <command>slave</command> zones respectively.
+ It is off by default.
+ </para>
+ </listitem>
+ </varlistentry>
-<programlisting>use-v4-udp-ports { range 1024 65535; };
-use-v6-udp-ports { range 1024 65535; };
-</programlisting>
+ <varlistentry>
+ <term><command>multi-master</command></term>
+ <listitem>
+ <para>
+ This should be set when you have multiple masters for a zone
+ and the
+ addresses refer to different machines. If <userinput>yes</userinput>, <command>named</command> will
+ not log
+ when the serial number on the master is less than what <command>named</command>
+ currently
+ has. The default is <userinput>no</userinput>.
+ </para>
+ </listitem>
+ </varlistentry>
- <para>
- Note: make sure the ranges be sufficiently large for
- security. A desirable size depends on various parameters,
- but we generally recommend it contain at least 16384 ports
- (14 bits of entropy).
- Note also that the system's default range when used may be
- too small for this purpose, and that the range may even be
- changed while <command>named</command> is running; the new
- range will automatically be applied when <command>named</command>
- is reloaded.
- It is encouraged to
- configure <command>use-v4-udp-ports</command> and
- <command>use-v6-udp-ports</command> explicitly so that the
- ranges are sufficiently large and are reasonably
- independent from the ranges used by other applications.
- </para>
+ <varlistentry>
+ <term><command>dnssec-enable</command></term>
+ <listitem>
+ <para>
+ Enable DNSSEC support in <command>named</command>. Unless set to <userinput>yes</userinput>,
+ <command>named</command> behaves as if it does not support DNSSEC.
+ The default is <userinput>yes</userinput>.
+ </para>
+ </listitem>
+ </varlistentry>
- <para>
- Note: the operational configuration
- where <command>named</command> runs may prohibit the use
- of some ports. For example, UNIX systems will not allow
- <command>named</command> running without a root privilege
- to use ports less than 1024.
- If such ports are included in the specified (or detected)
- set of query ports, the corresponding query attempts will
- fail, resulting in resolution failures or delay.
- It is therefore important to configure the set of ports
- that can be safely used in the expected operational environment.
- </para>
+ <varlistentry>
+ <term><command>dnssec-validation</command></term>
+ <listitem>
+ <para>
+ Enable DNSSEC validation in <command>named</command>.
+ Note <command>dnssec-enable</command> also needs to be
+ set to <userinput>yes</userinput> to be effective.
+ If set to <userinput>no</userinput>, DNSSEC validation
+ is disabled. If set to <userinput>auto</userinput>,
+ DNSSEC validation is enabled, and a default
+ trust-anchor for the DNS root zone is used. If set to
+ <userinput>yes</userinput>, DNSSEC validation is enabled,
+ but a trust anchor must be manually configured using
+ a <command>trusted-keys</command> or
+ <command>managed-keys</command> statement. The default
+ is <userinput>yes</userinput>.
+ </para>
+ </listitem>
+ </varlistentry>
- <para>
- The defaults of the <command>avoid-v4-udp-ports</command> and
- <command>avoid-v6-udp-ports</command> options
- are:
- </para>
+ <varlistentry>
+ <term><command>dnssec-accept-expired</command></term>
+ <listitem>
+ <para>
+ Accept expired signatures when verifying DNSSEC signatures.
+ The default is <userinput>no</userinput>.
+ Setting this option to <userinput>yes</userinput>
+ leaves <command>named</command> vulnerable to
+ replay attacks.
+ </para>
+ </listitem>
+ </varlistentry>
-<programlisting>avoid-v4-udp-ports {};
-avoid-v6-udp-ports {};
-</programlisting>
+ <varlistentry>
+ <term><command>querylog</command></term>
+ <listitem>
+ <para>
+ Specify whether query logging should be started when <command>named</command>
+ starts.
+ If <command>querylog</command> is not specified,
+ then the query logging
+ is determined by the presence of the logging category <command>queries</command>.
+ </para>
+ </listitem>
+ </varlistentry>
- <para>
- Note: BIND 9.5.0 introduced
- the <command>use-queryport-pool</command>
- option to support a pool of such random ports, but this
- option is now obsolete because reusing the same ports in
- the pool may not be sufficiently secure.
- For the same reason, it is generally strongly discouraged to
- specify a particular port for the
- <command>query-source</command> or
- <command>query-source-v6</command> options;
- it implicitly disables the use of randomized port numbers.
- </para>
+ <varlistentry>
+ <term><command>check-names</command></term>
+ <listitem>
+ <para>
+ This option is used to restrict the character set and syntax
+ of
+ certain domain names in master files and/or DNS responses
+ received
+ from the network. The default varies according to usage
+ area. For
+ <command>master</command> zones the default is <command>fail</command>.
+ For <command>slave</command> zones the default
+ is <command>warn</command>.
+ For answers received from the network (<command>response</command>)
+ the default is <command>ignore</command>.
+ </para>
+ <para>
+ The rules for legal hostnames and mail domains are derived
+ from RFC 952 and RFC 821 as modified by RFC 1123.
+ </para>
+ <para><command>check-names</command>
+ applies to the owner names of A, AAAA and MX records.
+ It also applies to the domain names in the RDATA of NS, SOA,
+ MX, and SRV records.
+ It also applies to the RDATA of PTR records where the owner
+ name indicated that it is a reverse lookup of a hostname
+ (the owner name ends in IN-ADDR.ARPA, IP6.ARPA, or IP6.INT).
+ </para>
+ </listitem>
+ </varlistentry>
- <variablelist>
- <varlistentry>
- <term><command>use-queryport-pool</command></term>
- <listitem>
- <para>
- This option is obsolete.
+ <varlistentry>
+ <term><command>check-dup-records</command></term>
+ <listitem>
+ <para>
+ Check master zones for records that are treated as different
+ by DNSSEC but are semantically equal in plain DNS. The
+ default is to <command>warn</command>. Other possible
+ values are <command>fail</command> and
+ <command>ignore</command>.
</para>
</listitem>
</varlistentry>
- <varlistentry>
- <term><command>queryport-pool-ports</command></term>
- <listitem>
- <para>
- This option is obsolete.
+ <varlistentry>
+ <term><command>check-mx</command></term>
+ <listitem>
+ <para>
+ Check whether the MX record appears to refer to a IP address.
+ The default is to <command>warn</command>. Other possible
+ values are <command>fail</command> and
+ <command>ignore</command>.
</para>
</listitem>
</varlistentry>
- <varlistentry>
- <term><command>queryport-pool-updateinterval</command></term>
- <listitem>
- <para>
- This option is obsolete.
+ <varlistentry>
+ <term><command>check-wildcard</command></term>
+ <listitem>
+ <para>
+ This option is used to check for non-terminal wildcards.
+ The use of non-terminal wildcards is almost always as a
+ result of a failure
+ to understand the wildcard matching algorithm (RFC 1034).
+ This option
+ affects master zones. The default (<command>yes</command>) is to check
+ for non-terminal wildcards and issue a warning.
</para>
</listitem>
</varlistentry>
-
- </variablelist>
- <note>
- <para>
- The address specified in the <command>query-source</command> option
- is used for both UDP and TCP queries, but the port applies only
- to UDP queries. TCP queries always use a random
- unprivileged port.
- </para>
- </note>
- <note>
- <para>
- Solaris 2.5.1 and earlier does not support setting the source
- address for TCP sockets.
- </para>
- </note>
- <note>
- <para>
- See also <command>transfer-source</command> and
- <command>notify-source</command>.
- </para>
- </note>
- </sect3>
-
- <sect3 id="zone_transfers">
- <title>Zone Transfers</title>
- <para>
- <acronym>BIND</acronym> has mechanisms in place to
- facilitate zone transfers
- and set limits on the amount of load that transfers place on the
- system. The following options apply to zone transfers.
- </para>
-
- <variablelist>
-
- <varlistentry>
- <term><command>also-notify</command></term>
- <listitem>
- <para>
- Defines a global list of IP addresses of name servers
- that are also sent NOTIFY messages whenever a fresh copy of
- the
- zone is loaded, in addition to the servers listed in the
- zone's NS records.
- This helps to ensure that copies of the zones will
- quickly converge on stealth servers.
- Optionally, a port may be specified with each
- <command>also-notify</command> address to send
- the notify messages to a port other than the
- default of 53.
- An optional TSIG key can also be specified with each
- address to cause the notify messages to be signed; this
- can be useful when sending notifies to multiple views.
- In place of explicit addresses, one or more named
- <command>masters</command> lists can be used.
- </para>
- <para>
- If an <command>also-notify</command> list
- is given in a <command>zone</command> statement,
- it will override
- the <command>options also-notify</command>
- statement. When a <command>zone notify</command>
- statement
- is set to <command>no</command>, the IP
- addresses in the global <command>also-notify</command> list will
- not be sent NOTIFY messages for that zone. The default is
- the empty
- list (no global notification list).
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>max-transfer-time-in</command></term>
- <listitem>
- <para>
- Inbound zone transfers running longer than
- this many minutes will be terminated. The default is 120
- minutes
- (2 hours). The maximum value is 28 days (40320 minutes).
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>max-transfer-idle-in</command></term>
- <listitem>
- <para>
- Inbound zone transfers making no progress
- in this many minutes will be terminated. The default is 60
- minutes
- (1 hour). The maximum value is 28 days (40320 minutes).
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>max-transfer-time-out</command></term>
- <listitem>
- <para>
- Outbound zone transfers running longer than
- this many minutes will be terminated. The default is 120
- minutes
- (2 hours). The maximum value is 28 days (40320 minutes).
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>max-transfer-idle-out</command></term>
- <listitem>
- <para>
- Outbound zone transfers making no progress
- in this many minutes will be terminated. The default is 60
- minutes (1
- hour). The maximum value is 28 days (40320 minutes).
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>serial-query-rate</command></term>
+
+ <varlistentry>
+ <term><command>check-integrity</command></term>
<listitem>
<para>
- Slave servers will periodically query master
- servers to find out if zone serial numbers have
- changed. Each such query uses a minute amount of
- the slave server's network bandwidth. To limit
- the amount of bandwidth used, BIND 9 limits the
- rate at which queries are sent. The value of the
- <command>serial-query-rate</command> option, an
- integer, is the maximum number of queries sent
- per second. The default is 20.
+ Perform post load zone integrity checks on master
+ zones. This checks that MX and SRV records refer
+ to address (A or AAAA) records and that glue
+ address records exist for delegated zones. For
+ MX and SRV records only in-zone hostnames are
+ checked (for out-of-zone hostnames use
+ <command>named-checkzone</command>).
+ For NS records only names below top of zone are
+ checked (for out-of-zone names and glue consistency
+ checks use <command>named-checkzone</command>).
+ The default is <command>yes</command>.
</para>
<para>
- In addition to controlling the rate SOA refresh
- queries are issued at
- <command>serial-query-rate</command> also controls
- the rate at which NOTIFY messages are sent from
- both master and slave zones.
+ Check that the two forms of Sender Policy Framework
+ records (TXT records starting with "v=spf1" and SPF) either
+ both exist or both don't exist. Warnings are
+ emitted it they don't and be suppressed with
+ <command>check-spf</command>.
</para>
</listitem>
</varlistentry>
- <varlistentry>
- <term><command>serial-queries</command></term>
- <listitem>
- <para>
- In BIND 8, the <command>serial-queries</command>
- option
- set the maximum number of concurrent serial number queries
- allowed to be outstanding at any given time.
- BIND 9 does not limit the number of outstanding
- serial queries and ignores the <command>serial-queries</command> option.
- Instead, it limits the rate at which the queries are sent
- as defined using the <command>serial-query-rate</command> option.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>transfer-format</command></term>
- <listitem>
-
- <para>
- Zone transfers can be sent using two different formats,
- <command>one-answer</command> and
- <command>many-answers</command>.
- The <command>transfer-format</command> option is used
- on the master server to determine which format it sends.
- <command>one-answer</command> uses one DNS message per
- resource record transferred.
- <command>many-answers</command> packs as many resource
- records as possible into a message.
- <command>many-answers</command> is more efficient, but is
- only supported by relatively new slave servers,
- such as <acronym>BIND</acronym> 9, <acronym>BIND</acronym>
- 8.x and <acronym>BIND</acronym> 4.9.5 onwards.
- The <command>many-answers</command> format is also supported by
- recent Microsoft Windows nameservers.
- The default is <command>many-answers</command>.
- <command>transfer-format</command> may be overridden on a
- per-server basis by using the <command>server</command>
- statement.
- </para>
-
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>transfers-in</command></term>
- <listitem>
- <para>
- The maximum number of inbound zone transfers
- that can be running concurrently. The default value is <literal>10</literal>.
- Increasing <command>transfers-in</command> may
- speed up the convergence
- of slave zones, but it also may increase the load on the
- local system.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>transfers-out</command></term>
- <listitem>
- <para>
- The maximum number of outbound zone transfers
- that can be running concurrently. Zone transfer requests in
- excess
- of the limit will be refused. The default value is <literal>10</literal>.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>transfers-per-ns</command></term>
- <listitem>
- <para>
- The maximum number of inbound zone transfers
- that can be concurrently transferring from a given remote
- name server.
- The default value is <literal>2</literal>.
- Increasing <command>transfers-per-ns</command>
- may
- speed up the convergence of slave zones, but it also may
- increase
- the load on the remote name server. <command>transfers-per-ns</command> may
- be overridden on a per-server basis by using the <command>transfers</command> phrase
- of the <command>server</command> statement.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>transfer-source</command></term>
- <listitem>
- <para><command>transfer-source</command>
- determines which local address will be bound to IPv4
- TCP connections used to fetch zones transferred
- inbound by the server. It also determines the
- source IPv4 address, and optionally the UDP port,
- used for the refresh queries and forwarded dynamic
- updates. If not set, it defaults to a system
- controlled value which will usually be the address
- of the interface "closest to" the remote end. This
- address must appear in the remote end's
- <command>allow-transfer</command> option for the
- zone being transferred, if one is specified. This
- statement sets the
- <command>transfer-source</command> for all zones,
- but can be overridden on a per-view or per-zone
- basis by including a
- <command>transfer-source</command> statement within
- the <command>view</command> or
- <command>zone</command> block in the configuration
- file.
- </para>
- <note>
- <para>
- Solaris 2.5.1 and earlier does not support setting the
- source address for TCP sockets.
- </para>
- </note>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>transfer-source-v6</command></term>
- <listitem>
- <para>
- The same as <command>transfer-source</command>,
- except zone transfers are performed using IPv6.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>alt-transfer-source</command></term>
- <listitem>
- <para>
- An alternate transfer source if the one listed in
- <command>transfer-source</command> fails and
- <command>use-alt-transfer-source</command> is
- set.
- </para>
- <note>
- If you do not wish the alternate transfer source
- to be used, you should set
- <command>use-alt-transfer-source</command>
- appropriately and you should not depend upon
- getting an answer back to the first refresh
- query.
- </note>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>alt-transfer-source-v6</command></term>
- <listitem>
- <para>
- An alternate transfer source if the one listed in
- <command>transfer-source-v6</command> fails and
- <command>use-alt-transfer-source</command> is
- set.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>use-alt-transfer-source</command></term>
- <listitem>
- <para>
- Use the alternate transfer sources or not. If views are
- specified this defaults to <command>no</command>
- otherwise it defaults to
- <command>yes</command> (for BIND 8
- compatibility).
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>notify-source</command></term>
- <listitem>
- <para><command>notify-source</command>
- determines which local source address, and
- optionally UDP port, will be used to send NOTIFY
- messages. This address must appear in the slave
- server's <command>masters</command> zone clause or
- in an <command>allow-notify</command> clause. This
- statement sets the <command>notify-source</command>
- for all zones, but can be overridden on a per-zone or
- per-view basis by including a
- <command>notify-source</command> statement within
- the <command>zone</command> or
- <command>view</command> block in the configuration
- file.
- </para>
- <note>
- <para>
- Solaris 2.5.1 and earlier does not support setting the
- source address for TCP sockets.
- </para>
- </note>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>notify-source-v6</command></term>
- <listitem>
- <para>
- Like <command>notify-source</command>,
- but applies to notify messages sent to IPv6 addresses.
- </para>
- </listitem>
- </varlistentry>
-
- </variablelist>
-
- </sect3>
-
- <sect3>
- <title>UDP Port Lists</title>
- <para>
- <command>use-v4-udp-ports</command>,
- <command>avoid-v4-udp-ports</command>,
- <command>use-v6-udp-ports</command>, and
- <command>avoid-v6-udp-ports</command>
- specify a list of IPv4 and IPv6 UDP ports that will be
- used or not used as source ports for UDP messages.
- See <xref linkend="query_address"/> about how the
- available ports are determined.
- For example, with the following configuration
- </para>
+ <varlistentry>
+ <term><command>check-mx-cname</command></term>
+ <listitem>
+ <para>
+ If <command>check-integrity</command> is set then
+ fail, warn or ignore MX records that refer
+ to CNAMES. The default is to <command>warn</command>.
+ </para>
+ </listitem>
+ </varlistentry>
-<programlisting>
-use-v6-udp-ports { range 32768 65535; };
-avoid-v6-udp-ports { 40000; range 50000 60000; };
-</programlisting>
+ <varlistentry>
+ <term><command>check-srv-cname</command></term>
+ <listitem>
+ <para>
+ If <command>check-integrity</command> is set then
+ fail, warn or ignore SRV records that refer
+ to CNAMES. The default is to <command>warn</command>.
+ </para>
+ </listitem>
+ </varlistentry>
- <para>
- UDP ports of IPv6 messages sent
- from <command>named</command> will be in one
- of the following ranges: 32768 to 39999, 40001 to 49999,
- and 60001 to 65535.
- </para>
-
- <para>
- <command>avoid-v4-udp-ports</command> and
- <command>avoid-v6-udp-ports</command> can be used
- to prevent <command>named</command> from choosing as its random source port a
- port that is blocked by your firewall or a port that is
- used by other applications;
- if a query went out with a source port blocked by a
- firewall, the
- answer would not get by the firewall and the name server would
- have to query again.
- Note: the desired range can also be represented only with
- <command>use-v4-udp-ports</command> and
- <command>use-v6-udp-ports</command>, and the
- <command>avoid-</command> options are redundant in that
- sense; they are provided for backward compatibility and
- to possibly simplify the port specification.
- </para>
- </sect3>
-
- <sect3>
- <title>Operating System Resource Limits</title>
-
- <para>
- The server's usage of many system resources can be limited.
- Scaled values are allowed when specifying resource limits. For
- example, <command>1G</command> can be used instead of
- <command>1073741824</command> to specify a limit of
- one
- gigabyte. <command>unlimited</command> requests
- unlimited use, or the
- maximum available amount. <command>default</command>
- uses the limit
- that was in force when the server was started. See the description
- of <command>size_spec</command> in <xref linkend="configuration_file_elements"/>.
- </para>
-
- <para>
- The following options set operating system resource limits for
- the name server process. Some operating systems don't support
- some or
- any of the limits. On such systems, a warning will be issued if
- the
- unsupported limit is used.
- </para>
-
- <variablelist>
-
- <varlistentry>
- <term><command>coresize</command></term>
- <listitem>
- <para>
- The maximum size of a core dump. The default
- is <literal>default</literal>.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>datasize</command></term>
- <listitem>
- <para>
- The maximum amount of data memory the server
- may use. The default is <literal>default</literal>.
- This is a hard limit on server memory usage.
- If the server attempts to allocate memory in excess of this
- limit, the allocation will fail, which may in turn leave
- the server unable to perform DNS service. Therefore,
- this option is rarely useful as a way of limiting the
- amount of memory used by the server, but it can be used
- to raise an operating system data size limit that is
- too small by default. If you wish to limit the amount
- of memory used by the server, use the
- <command>max-cache-size</command> and
- <command>recursive-clients</command>
- options instead.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>files</command></term>
- <listitem>
- <para>
- The maximum number of files the server
- may have open concurrently. The default is <literal>unlimited</literal>.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>stacksize</command></term>
- <listitem>
- <para>
- The maximum amount of stack memory the server
- may use. The default is <literal>default</literal>.
- </para>
- </listitem>
- </varlistentry>
-
- </variablelist>
-
- </sect3>
-
- <sect3 id="server_resource_limits">
- <title>Server Resource Limits</title>
-
- <para>
- The following options set limits on the server's
- resource consumption that are enforced internally by the
- server rather than the operating system.
- </para>
-
- <variablelist>
-
- <varlistentry>
- <term><command>max-ixfr-log-size</command></term>
- <listitem>
- <para>
- This option is obsolete; it is accepted
- and ignored for BIND 8 compatibility. The option
- <command>max-journal-size</command> performs a
- similar function in BIND 9.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>max-journal-size</command></term>
- <listitem>
- <para>
- Sets a maximum size for each journal file
- (see <xref linkend="journal"/>). When the journal file
- approaches
- the specified size, some of the oldest transactions in the
- journal
- will be automatically removed. The largest permitted
- value is 2 gigabytes. The default is
- <literal>unlimited</literal>, which also
- means 2 gigabytes.
- This may also be set on a per-zone basis.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>host-statistics-max</command></term>
- <listitem>
- <para>
- In BIND 8, specifies the maximum number of host statistics
- entries to be kept.
- Not implemented in BIND 9.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>recursive-clients</command></term>
- <listitem>
- <para>
- The maximum number of simultaneous recursive lookups
- the server will perform on behalf of clients. The default
- is
- <literal>1000</literal>. Because each recursing
- client uses a fair
- bit of memory, on the order of 20 kilobytes, the value of
- the
- <command>recursive-clients</command> option may
- have to be decreased
- on hosts with limited memory.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>tcp-clients</command></term>
- <listitem>
- <para>
- The maximum number of simultaneous client TCP
- connections that the server will accept.
- The default is <literal>100</literal>.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>reserved-sockets</command></term>
- <listitem>
- <para>
- The number of file descriptors reserved for TCP, stdio,
- etc. This needs to be big enough to cover the number of
- interfaces <command>named</command> listens on, <command>tcp-clients</command> as well as
- to provide room for outgoing TCP queries and incoming zone
- transfers. The default is <literal>512</literal>.
- The minimum value is <literal>128</literal> and the
- maximum value is <literal>128</literal> less than
- maxsockets (-S). This option may be removed in the future.
- </para>
- <para>
- This option has little effect on Windows.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>max-cache-size</command></term>
- <listitem>
- <para>
- The maximum amount of memory to use for the
- server's cache, in bytes.
- When the amount of data in the cache
- reaches this limit, the server will cause records to
- expire prematurely based on an LRU based strategy so
- that the limit is not exceeded.
- The keyword <userinput>unlimited</userinput>,
- or the value 0, will place no limit on cache size;
- records will be purged from the cache only when their
- TTLs expire.
- Any positive values less than 2MB will be ignored
- and reset to 2MB.
- In a server with multiple views, the limit applies
- separately to the cache of each view.
- The default is <userinput>unlimited</userinput>.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>tcp-listen-queue</command></term>
- <listitem>
- <para>
- The listen queue depth. The default and minimum is 10.
- If the kernel supports the accept filter "dataready" this
- also controls how
- many TCP connections that will be queued in kernel space
- waiting for
- some data before being passed to accept. Nonzero values
- less than 10 will be silently raised. A value of 0 may also
- be used; on most platforms this sets the listen queue
- length to a system-defined default value.
- </para>
- </listitem>
- </varlistentry>
-
- </variablelist>
-
- </sect3>
-
- <sect3>
- <title>Periodic Task Intervals</title>
-
- <variablelist>
-
- <varlistentry>
- <term><command>cleaning-interval</command></term>
- <listitem>
- <para>
- This interval is effectively obsolete. Previously,
- the server would remove expired resource records
- from the cache every <command>cleaning-interval</command> minutes.
- <acronym>BIND</acronym> 9 now manages cache
- memory in a more sophisticated manner and does not
- rely on the periodic cleaning any more.
- Specifying this option therefore has no effect on
- the server's behavior.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>heartbeat-interval</command></term>
- <listitem>
- <para>
- The server will perform zone maintenance tasks
- for all zones marked as <command>dialup</command> whenever this
- interval expires. The default is 60 minutes. Reasonable
- values are up
- to 1 day (1440 minutes). The maximum value is 28 days
- (40320 minutes).
- If set to 0, no zone maintenance for these zones will occur.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>interface-interval</command></term>
- <listitem>
- <para>
- The server will scan the network interface list
- every <command>interface-interval</command>
- minutes. The default
- is 60 minutes. The maximum value is 28 days (40320 minutes).
- If set to 0, interface scanning will only occur when
- the configuration file is loaded. After the scan, the
- server will
- begin listening for queries on any newly discovered
- interfaces (provided they are allowed by the
- <command>listen-on</command> configuration), and
- will
- stop listening on interfaces that have gone away.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>statistics-interval</command></term>
- <listitem>
- <para>
- Name server statistics will be logged
- every <command>statistics-interval</command>
- minutes. The default is
- 60. The maximum value is 28 days (40320 minutes).
- If set to 0, no statistics will be logged.
- </para><note>
- <simpara>
- Not yet implemented in
- <acronym>BIND</acronym> 9.
- </simpara>
- </note>
- </listitem>
- </varlistentry>
-
- </variablelist>
-
- </sect3>
-
- <sect3 id="topology">
- <title>Topology</title>
-
- <para>
- All other things being equal, when the server chooses a name
- server
- to query from a list of name servers, it prefers the one that is
- topologically closest to itself. The <command>topology</command> statement
- takes an <command>address_match_list</command> and
- interprets it
- in a special way. Each top-level list element is assigned a
- distance.
- Non-negated elements get a distance based on their position in the
- list, where the closer the match is to the start of the list, the
- shorter the distance is between it and the server. A negated match
- will be assigned the maximum distance from the server. If there
- is no match, the address will get a distance which is further than
- any non-negated list element, and closer than any negated element.
- For example,
- </para>
-
-<programlisting>topology {
- 10/8;
- !1.2.3/24;
- { 1.2/16; 3/8; };
-};</programlisting>
-
- <para>
- will prefer servers on network 10 the most, followed by hosts
- on network 1.2.0.0 (netmask 255.255.0.0) and network 3, with the
- exception of hosts on network 1.2.3 (netmask 255.255.255.0), which
- is preferred least of all.
- </para>
- <para>
- The default topology is
- </para>
-
-<programlisting> topology { localhost; localnets; };
-</programlisting>
-
- <note>
- <simpara>
- The <command>topology</command> option
- is not implemented in <acronym>BIND</acronym> 9.
- </simpara>
- </note>
- </sect3>
-
- <sect3 id="the_sortlist_statement">
-
- <title>The <command>sortlist</command> Statement</title>
-
- <para>
- The response to a DNS query may consist of multiple resource
- records (RRs) forming a resource records set (RRset).
- The name server will normally return the
- RRs within the RRset in an indeterminate order
- (but see the <command>rrset-order</command>
- statement in <xref linkend="rrset_ordering"/>).
- The client resolver code should rearrange the RRs as appropriate,
- that is, using any addresses on the local net in preference to
- other addresses.
- However, not all resolvers can do this or are correctly
- configured.
- When a client is using a local server, the sorting can be performed
- in the server, based on the client's address. This only requires
- configuring the name servers, not all the clients.
- </para>
-
- <para>
- The <command>sortlist</command> statement (see below)
- takes
- an <command>address_match_list</command> and
- interprets it even
- more specifically than the <command>topology</command>
- statement
- does (<xref linkend="topology"/>).
- Each top level statement in the <command>sortlist</command> must
- itself be an explicit <command>address_match_list</command> with
- one or two elements. The first element (which may be an IP
- address,
- an IP prefix, an ACL name or a nested <command>address_match_list</command>)
- of each top level list is checked against the source address of
- the query until a match is found.
- </para>
- <para>
- Once the source address of the query has been matched, if
- the top level statement contains only one element, the actual
- primitive
- element that matched the source address is used to select the
- address
- in the response to move to the beginning of the response. If the
- statement is a list of two elements, then the second element is
- treated the same as the <command>address_match_list</command> in
- a <command>topology</command> statement. Each top
- level element
- is assigned a distance and the address in the response with the
- minimum
- distance is moved to the beginning of the response.
- </para>
- <para>
- In the following example, any queries received from any of
- the addresses of the host itself will get responses preferring
- addresses
- on any of the locally connected networks. Next most preferred are
- addresses
- on the 192.168.1/24 network, and after that either the
- 192.168.2/24
- or
- 192.168.3/24 network with no preference shown between these two
- networks. Queries received from a host on the 192.168.1/24 network
- will prefer other addresses on that network to the 192.168.2/24
- and
- 192.168.3/24 networks. Queries received from a host on the
- 192.168.4/24
- or the 192.168.5/24 network will only prefer other addresses on
- their directly connected networks.
- </para>
-
-<programlisting>sortlist {
- // IF the local host
- // THEN first fit on the following nets
- { localhost;
- { localnets;
- 192.168.1/24;
- { 192.168.2/24; 192.168.3/24; }; }; };
- // IF on class C 192.168.1 THEN use .1, or .2 or .3
- { 192.168.1/24;
- { 192.168.1/24;
- { 192.168.2/24; 192.168.3/24; }; }; };
- // IF on class C 192.168.2 THEN use .2, or .1 or .3
- { 192.168.2/24;
- { 192.168.2/24;
- { 192.168.1/24; 192.168.3/24; }; }; };
- // IF on class C 192.168.3 THEN use .3, or .1 or .2
- { 192.168.3/24;
- { 192.168.3/24;
- { 192.168.1/24; 192.168.2/24; }; }; };
- // IF .4 or .5 THEN prefer that net
- { { 192.168.4/24; 192.168.5/24; };
- };
-};</programlisting>
-
- <para>
- The following example will give reasonable behavior for the
- local host and hosts on directly connected networks. It is similar
- to the behavior of the address sort in <acronym>BIND</acronym> 4.9.x. Responses sent
- to queries from the local host will favor any of the directly
- connected
- networks. Responses sent to queries from any other hosts on a
- directly
- connected network will prefer addresses on that same network.
- Responses
- to other queries will not be sorted.
- </para>
-
-<programlisting>sortlist {
- { localhost; localnets; };
- { localnets; };
-};
-</programlisting>
-
- </sect3>
- <sect3 id="rrset_ordering">
- <title id="rrset_ordering_title">RRset Ordering</title>
- <para>
- When multiple records are returned in an answer it may be
- useful to configure the order of the records placed into the
- response.
- The <command>rrset-order</command> statement permits
- configuration
- of the ordering of the records in a multiple record response.
- See also the <command>sortlist</command> statement,
- <xref linkend="the_sortlist_statement"/>.
- </para>
-
- <para>
- An <command>order_spec</command> is defined as
- follows:
- </para>
- <para>
- <optional>class <replaceable>class_name</replaceable></optional>
- <optional>type <replaceable>type_name</replaceable></optional>
- <optional>name <replaceable>"domain_name"</replaceable></optional>
- order <replaceable>ordering</replaceable>
- </para>
- <para>
- If no class is specified, the default is <command>ANY</command>.
- If no type is specified, the default is <command>ANY</command>.
- If no name is specified, the default is "<command>*</command>" (asterisk).
- </para>
- <para>
- The legal values for <command>ordering</command> are:
- </para>
- <informaltable colsep="0" rowsep="0">
- <tgroup cols="2" colsep="0" rowsep="0" tgroupstyle="4Level-table">
- <colspec colname="1" colnum="1" colsep="0" colwidth="0.750in"/>
- <colspec colname="2" colnum="2" colsep="0" colwidth="3.750in"/>
- <tbody>
- <row rowsep="0">
- <entry colname="1">
- <para><command>fixed</command></para>
- </entry>
- <entry colname="2">
- <para>
- Records are returned in the order they
- are defined in the zone file.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para><command>random</command></para>
- </entry>
- <entry colname="2">
- <para>
- Records are returned in some random order.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para><command>cyclic</command></para>
- </entry>
- <entry colname="2">
- <para>
- Records are returned in a cyclic round-robin order.
- </para>
- <para>
- If <acronym>BIND</acronym> is configured with the
- "--enable-fixed-rrset" option at compile time, then
- the initial ordering of the RRset will match the
- one specified in the zone file.
- </para>
- </entry>
- </row>
- </tbody>
- </tgroup>
- </informaltable>
- <para>
- For example:
- </para>
-
-<programlisting>rrset-order {
- class IN type A name "host.example.com" order random;
- order cyclic;
-};
-</programlisting>
-
- <para>
- will cause any responses for type A records in class IN that
- have "<literal>host.example.com</literal>" as a
- suffix, to always be returned
- in random order. All other records are returned in cyclic order.
- </para>
- <para>
- If multiple <command>rrset-order</command> statements
- appear, they are not combined — the last one applies.
- </para>
- <para>
- By default, all records are returned in random order.
- </para>
-
- <note>
- <simpara>
- In this release of <acronym>BIND</acronym> 9, the
- <command>rrset-order</command> statement does not support
- "fixed" ordering by default. Fixed ordering can be enabled
- at compile time by specifying "--enable-fixed-rrset" on
- the "configure" command line.
- </simpara>
- </note>
- </sect3>
-
- <sect3 id="tuning">
- <title>Tuning</title>
-
- <variablelist>
-
- <varlistentry>
- <term><command>lame-ttl</command></term>
- <listitem>
- <para>
- Sets the number of seconds to cache a
- lame server indication. 0 disables caching. (This is
- <emphasis role="bold">NOT</emphasis> recommended.)
- The default is <literal>600</literal> (10 minutes) and the
- maximum value is
- <literal>1800</literal> (30 minutes).
- </para>
-
- <para>
- Lame-ttl also controls the amount of time DNSSEC
- validation failures are cached. There is a minimum
- of 30 seconds applied to bad cache entries if the
- lame-ttl is set to less than 30 seconds.
- </para>
-
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>max-ncache-ttl</command></term>
- <listitem>
- <para>
- To reduce network traffic and increase performance,
- the server stores negative answers. <command>max-ncache-ttl</command> is
- used to set a maximum retention time for these answers in
- the server
- in seconds. The default
- <command>max-ncache-ttl</command> is <literal>10800</literal> seconds (3 hours).
- <command>max-ncache-ttl</command> cannot exceed
- 7 days and will
- be silently truncated to 7 days if set to a greater value.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>max-cache-ttl</command></term>
- <listitem>
- <para>
- Sets the maximum time for which the server will
- cache ordinary (positive) answers. The default is
- one week (7 days).
- A value of zero may cause all queries to return
- SERVFAIL, because of lost caches of intermediate
- RRsets (such as NS and glue AAAA/A records) in the
- resolution process.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>min-roots</command></term>
- <listitem>
- <para>
- The minimum number of root servers that
- is required for a request for the root servers to be
- accepted. The default
- is <userinput>2</userinput>.
- </para>
- <note>
- <simpara>
- Not implemented in <acronym>BIND</acronym> 9.
- </simpara>
- </note>
- </listitem>
- </varlistentry>
+ <varlistentry>
+ <term><command>check-sibling</command></term>
+ <listitem>
+ <para>
+ When performing integrity checks, also check that
+ sibling glue exists. The default is <command>yes</command>.
+ </para>
+ </listitem>
+ </varlistentry>
<varlistentry>
- <term><command>sig-validity-interval</command></term>
+ <term><command>check-spf</command></term>
<listitem>
<para>
- Specifies the number of days into the future when
- DNSSEC signatures automatically generated as a
- result of dynamic updates (<xref
- linkend="dynamic_update"/>) will expire. There
- is an optional second field which specifies how
- long before expiry that the signatures will be
- regenerated. If not specified, the signatures will
- be regenerated at 1/4 of base interval. The second
- field is specified in days if the base interval is
- greater than 7 days otherwise it is specified in hours.
- The default base interval is <literal>30</literal> days
- giving a re-signing interval of 7 1/2 days. The maximum
- values are 10 years (3660 days).
- </para>
- <para>
- The signature inception time is unconditionally
- set to one hour before the current time to allow
- for a limited amount of clock skew.
- </para>
- <para>
- The <command>sig-validity-interval</command>
- should be, at least, several multiples of the SOA
- expire interval to allow for reasonable interaction
- between the various timer and expiry dates.
+ When performing integrity checks, check that the
+ two forms of Sender Policy Framwork records (TXT
+ records starting with "v=spf1" and SPF) both exist
+ or both don't exist and issue a warning if not
+ met. The default is <command>warn</command>.
</para>
</listitem>
</varlistentry>
<varlistentry>
- <term><command>sig-signing-nodes</command></term>
+ <term><command>zero-no-soa-ttl</command></term>
<listitem>
<para>
- Specify the maximum number of nodes to be
- examined in each quantum when signing a zone with
- a new DNSKEY. The default is
- <literal>100</literal>.
+ When returning authoritative negative responses to
+ SOA queries set the TTL of the SOA record returned in
+ the authority section to zero.
+ The default is <command>yes</command>.
</para>
</listitem>
</varlistentry>
<varlistentry>
- <term><command>sig-signing-signatures</command></term>
+ <term><command>zero-no-soa-ttl-cache</command></term>
<listitem>
<para>
- Specify a threshold number of signatures that
- will terminate processing a quantum when signing
- a zone with a new DNSKEY. The default is
- <literal>10</literal>.
+ When caching a negative response to a SOA query
+ set the TTL to zero.
+ The default is <command>no</command>.
</para>
</listitem>
</varlistentry>
<varlistentry>
- <term><command>sig-signing-type</command></term>
+ <term><command>update-check-ksk</command></term>
<listitem>
<para>
- Specify a private RDATA type to be used when generating
- key signing records. The default is
- <literal>65534</literal>.
+ When set to the default value of <literal>yes</literal>,
+ check the KSK bit in each key to determine how the key
+ should be used when generating RRSIGs for a secure zone.
</para>
<para>
- It is expected that this parameter may be removed
- in a future version once there is a standard type.
+ Ordinarily, zone-signing keys (that is, keys without the
+ KSK bit set) are used to sign the entire zone, while
+ key-signing keys (keys with the KSK bit set) are only
+ used to sign the DNSKEY RRset at the zone apex.
+ However, if this option is set to <literal>no</literal>,
+ then the KSK bit is ignored; KSKs are treated as if they
+ were ZSKs and are used to sign the entire zone. This is
+ similar to the <command>dnssec-signzone -z</command>
+ command line option.
</para>
<para>
- These records can be removed from the zone once named
- has completed signing the zone with the matching key
- using <command>nsupdate</command> or
- <command>rndc signing -clear</command>.
- <command>rndc signing -clear</command> is the only supported
- way to remove these records from
- <command>inline-signing</command> zones.
+ When this option is set to <literal>yes</literal>, there
+ must be at least two active keys for every algorithm
+ represented in the DNSKEY RRset: at least one KSK and one
+ ZSK per algorithm. If there is any algorithm for which
+ this requirement is not met, this option will be ignored
+ for that algorithm.
</para>
</listitem>
</varlistentry>
- <varlistentry>
- <term><command>min-refresh-time</command></term>
- <term><command>max-refresh-time</command></term>
- <term><command>min-retry-time</command></term>
- <term><command>max-retry-time</command></term>
- <listitem>
- <para>
- These options control the server's behavior on refreshing a
- zone
- (querying for SOA changes) or retrying failed transfers.
- Usually the SOA values for the zone are used, but these
- values
- are set by the master, giving slave server administrators
- little
- control over their contents.
- </para>
- <para>
- These options allow the administrator to set a minimum and
- maximum
- refresh and retry time either per-zone, per-view, or
- globally.
- These options are valid for slave and stub zones,
- and clamp the SOA refresh and retry times to the specified
- values.
- </para>
+ <varlistentry>
+ <term><command>dnssec-dnskey-kskonly</command></term>
+ <listitem>
<para>
- The following defaults apply.
- <command>min-refresh-time</command> 300 seconds,
- <command>max-refresh-time</command> 2419200 seconds
- (4 weeks), <command>min-retry-time</command> 500 seconds,
- and <command>max-retry-time</command> 1209600 seconds
- (2 weeks).
+ When this option and <command>update-check-ksk</command>
+ are both set to <literal>yes</literal>, only key-signing
+ keys (that is, keys with the KSK bit set) will be used
+ to sign the DNSKEY RRset at the zone apex. Zone-signing
+ keys (keys without the KSK bit set) will be used to sign
+ the remainder of the zone, but not the DNSKEY RRset.
+ This is similar to the
+ <command>dnssec-signzone -x</command> command line option.
</para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>edns-udp-size</command></term>
- <listitem>
- <para>
- Sets the advertised EDNS UDP buffer size in bytes
- to control the size of packets received.
- Valid values are 512 to 4096 (values outside this range
- will be silently adjusted). The default value
- is 4096. The usual reason for setting
- <command>edns-udp-size</command> to a non-default
- value is to get UDP answers to pass through broken
- firewalls that block fragmented packets and/or
- block UDP packets that are greater than 512 bytes.
- </para>
<para>
- <command>named</command> will fallback to using 512 bytes
- if it get a series of timeout at the initial value. 512
- bytes is not being offered to encourage sites to fix their
- firewalls. Small EDNS UDP sizes will result in the
- excessive use of TCP.
+ The default is <command>no</command>. If
+ <command>update-check-ksk</command> is set to
+ <literal>no</literal>, this option is ignored.
</para>
- </listitem>
- </varlistentry>
+ </listitem>
+ </varlistentry>
- <varlistentry>
- <term><command>max-udp-size</command></term>
+ <varlistentry>
+ <term><command>dnssec-loadkeys-interval</command></term>
<listitem>
<para>
- Sets the maximum EDNS UDP message size
- <command>named</command> will send in bytes.
- Valid values are 512 to 4096 (values outside this
- range will be silently adjusted). The default
- value is 4096. The usual reason for setting
- <command>max-udp-size</command> to a non-default
- value is to get UDP answers to pass through broken
- firewalls that block fragmented packets and/or
- block UDP packets that are greater than 512 bytes.
- This is independent of the advertised receive
- buffer (<command>edns-udp-size</command>).
- </para>
- <para>
- Setting this to a low value will encourage additional
- TCP traffic to the nameserver.
+ When a zone is configured with <command>auto-dnssec
+ maintain;</command> its key repository must be checked
+ periodically to see if any new keys have been added
+ or any existing keys' timing metadata has been updated
+ (see <xref linkend="man.dnssec-keygen"/> and
+ <xref linkend="man.dnssec-settime"/>). The
+ <command>dnssec-loadkeys-interval</command> option
+ sets the frequency of automatic repository checks, in
+ minutes. The default is <literal>60</literal> (1 hour),
+ the minimum is <literal>1</literal> (1 minute), and the
+ maximum is <literal>1440</literal> (24 hours); any higher
+ value is silently reduced.
</para>
</listitem>
</varlistentry>
<varlistentry>
- <term><command>masterfile-format</command></term>
+ <term><command>try-tcp-refresh</command></term>
<listitem>
- <para>Specifies
- the file format of zone files (see
- <xref linkend="zonefile_format"/>).
- The default value is <constant>text</constant>, which is the
- standard textual representation, except for slave zones,
- in which the default value is <constant>raw</constant>.
- Files in other formats than <constant>text</constant> are
- typically expected to be generated by the
- <command>named-compilezone</command> tool, or dumped by
- <command>named</command>.
- </para>
- <para>
- Note that when a zone file in a different format than
- <constant>text</constant> is loaded, <command>named</command>
- may omit some of the checks which would be performed for a
- file in the <constant>text</constant> format. In particular,
- <command>check-names</command> checks do not apply
- for the <constant>raw</constant> format. This means
- a zone file in the <constant>raw</constant> format
- must be generated with the same check level as that
- specified in the <command>named</command> configuration
- file. Also, <constant>map</constant> format files are
- loaded directly into memory via memory mapping, with only
- minimal checking.
- </para>
- <para>
- This statement sets the
- <command>masterfile-format</command> for all zones,
- but can be overridden on a per-zone or per-view basis
- by including a <command>masterfile-format</command>
- statement within the <command>zone</command> or
- <command>view</command> block in the configuration
- file.
- </para>
+ <para>
+ Try to refresh the zone using TCP if UDP queries fail.
+ For BIND 8 compatibility, the default is
+ <command>yes</command>.
+ </para>
</listitem>
</varlistentry>
- <varlistentry id="clients-per-query">
- <term><command>clients-per-query</command></term>
- <term><command>max-clients-per-query</command></term>
- <listitem>
- <para>These set the
- initial value (minimum) and maximum number of recursive
- simultaneous clients for any given query
- (<qname,qtype,qclass>) that the server will accept
- before dropping additional clients. <command>named</command> will attempt to
- self tune this value and changes will be logged. The
- default values are 10 and 100.
- </para>
+ <varlistentry>
+ <term><command>dnssec-secure-to-insecure</command></term>
+ <listitem>
<para>
- This value should reflect how many queries come in for
- a given name in the time it takes to resolve that name.
- If the number of queries exceed this value, <command>named</command> will
- assume that it is dealing with a non-responsive zone
- and will drop additional queries. If it gets a response
- after dropping queries, it will raise the estimate. The
- estimate will then be lowered in 20 minutes if it has
- remained unchanged.
+ Allow a dynamic zone to transition from secure to
+ insecure (i.e., signed to unsigned) by deleting all
+ of the DNSKEY records. The default is <command>no</command>.
+ If set to <command>yes</command>, and if the DNSKEY RRset
+ at the zone apex is deleted, all RRSIG and NSEC records
+ will be removed from the zone as well.
</para>
<para>
- If <command>clients-per-query</command> is set to zero,
- then there is no limit on the number of clients per query
- and no queries will be dropped.
+ If the zone uses NSEC3, then it is also necessary to
+ delete the NSEC3PARAM RRset from the zone apex; this will
+ cause the removal of all corresponding NSEC3 records.
+ (It is expected that this requirement will be eliminated
+ in a future release.)
</para>
<para>
- If <command>max-clients-per-query</command> is set to zero,
- then there is no upper bound other than imposed by
- <command>recursive-clients</command>.
+ Note that if a zone has been configured with
+ <command>auto-dnssec maintain</command> and the
+ private keys remain accessible in the key repository,
+ then the zone will be automatically signed again the
+ next time <command>named</command> is started.
</para>
- </listitem>
+ </listitem>
</varlistentry>
- <varlistentry>
- <term><command>notify-delay</command></term>
- <listitem>
- <para>
- The delay, in seconds, between sending sets of notify
- messages for a zone. The default is five (5) seconds.
- </para>
- <para>
- The overall rate that NOTIFY messages are sent for all
- zones is controlled by <command>serial-query-rate</command>.
- </para>
- </listitem>
- </varlistentry>
+ </variablelist>
- <varlistentry>
- <term><command>max-rsa-exponent-size</command></term>
- <listitem>
- <para>
- The maximum RSA exponent size, in bits, that will
- be accepted when validating. Valid values are 35
- to 4096 bits. The default zero (0) is also accepted
- and is equivalent to 4096.
- </para>
- </listitem>
- </varlistentry>
+ </sect3>
+ <sect3>
+ <title>Forwarding</title>
+ <para>
+ The forwarding facility can be used to create a large site-wide
+ cache on a few servers, reducing traffic over links to external
+ name servers. It can also be used to allow queries by servers that
+ do not have direct access to the Internet, but wish to look up
+ exterior
+ names anyway. Forwarding occurs only on those queries for which
+ the server is not authoritative and does not have the answer in
+ its cache.
+ </para>
+
+ <variablelist>
<varlistentry>
- <term><command>prefetch</command></term>
+ <term><command>forward</command></term>
<listitem>
<para>
- When a query is received for cached data which
- is to expire shortly, <command>named</command> can
- refresh the data from the authoritative server
- immediately, ensuring that the cache always has an
- answer available.
+ This option is only meaningful if the
+ forwarders list is not empty. A value of <varname>first</varname>,
+ the default, causes the server to query the forwarders
+ first — and
+ if that doesn't answer the question, the server will then
+ look for
+ the answer itself. If <varname>only</varname> is
+ specified, the
+ server will only query the forwarders.
</para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>forwarders</command></term>
+ <listitem>
<para>
- The <option>prefetch</option> specifies the the
- "trigger" TTL value at which prefetch of the current
- query will take place: when a cache record with a
- lower TTL value is encountered during query processing,
- it will be refreshed. Valid trigger TTL values are 1 to
- 10 seconds. Setting a trigger TTL to zero disables
- prefetch.
- </para>
- <para>
- An optional second argument can be used
- to set the smallest <emphasis>original</emphasis>
- TTL value that will be accepted for a record to be
- eligible for prefetching. The difference between
- the trigger TTL and the eligibility TTL must be
- at least 6 seconds.
- </para>
- <para>
- The default trigger and eligibility TTLs are
- <literal>2</literal> and <literal>9</literal>,
- respectively.
+ Specifies the IP addresses to be used
+ for forwarding. The default is the empty list (no
+ forwarding).
</para>
</listitem>
</varlistentry>
+
</variablelist>
- </sect3>
-
- <sect3 id="builtin">
- <title>Built-in server information zones</title>
-
- <para>
- The server provides some helpful diagnostic information
- through a number of built-in zones under the
- pseudo-top-level-domain <literal>bind</literal> in the
- <command>CHAOS</command> class. These zones are part
- of a
- built-in view (see <xref linkend="view_statement_grammar"/>) of
- class
- <command>CHAOS</command> which is separate from the
- default view of class <command>IN</command>. Most global
- configuration options (<command>allow-query</command>,
- etc) will apply to this view, but some are locally
- overridden: <command>notify</command>,
- <command>recursion</command> and
- <command>allow-new-zones</command> are
- always set to <userinput>no</userinput>, and
- <command>rate-limit</command> is set to allow
- three responses per second.
- </para>
- <para>
- If you need to disable these zones, use the options
- below, or hide the built-in <command>CHAOS</command>
- view by
- defining an explicit view of class <command>CHAOS</command>
- that matches all clients.
- </para>
-
- <variablelist>
-
- <varlistentry>
- <term><command>version</command></term>
- <listitem>
- <para>
- The version the server should report
- via a query of the name <literal>version.bind</literal>
- with type <command>TXT</command>, class <command>CHAOS</command>.
- The default is the real version number of this server.
- Specifying <command>version none</command>
- disables processing of the queries.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>hostname</command></term>
- <listitem>
- <para>
- The hostname the server should report via a query of
- the name <filename>hostname.bind</filename>
- with type <command>TXT</command>, class <command>CHAOS</command>.
- This defaults to the hostname of the machine hosting the
- name server as
- found by the gethostname() function. The primary purpose of such queries
- is to
- identify which of a group of anycast servers is actually
- answering your queries. Specifying <command>hostname none;</command>
- disables processing of the queries.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>server-id</command></term>
- <listitem>
- <para>
- The ID the server should report when receiving a Name
- Server Identifier (NSID) query, or a query of the name
- <filename>ID.SERVER</filename> with type
- <command>TXT</command>, class <command>CHAOS</command>.
- The primary purpose of such queries is to
- identify which of a group of anycast servers is actually
- answering your queries. Specifying <command>server-id none;</command>
- disables processing of the queries.
- Specifying <command>server-id hostname;</command> will cause <command>named</command> to
- use the hostname as found by the gethostname() function.
- The default <command>server-id</command> is <command>none</command>.
- </para>
- </listitem>
- </varlistentry>
-
- </variablelist>
-
- </sect3>
-
- <sect3 id="empty">
- <title>Built-in Empty Zones</title>
- <para>
- Named has some built-in empty zones (SOA and NS records only).
- These are for zones that should normally be answered locally
- and which queries should not be sent to the Internet's root
- servers. The official servers which cover these namespaces
- return NXDOMAIN responses to these queries. In particular,
- these cover the reverse namespaces for addresses from
- RFC 1918, RFC 4193, RFC 5737 and RFC 6598. They also include the
- reverse namespace for IPv6 local address (locally assigned),
- IPv6 link local addresses, the IPv6 loopback address and the
- IPv6 unknown address.
- </para>
- <para>
- Named will attempt to determine if a built-in zone already exists
- or is active (covered by a forward-only forwarding declaration)
- and will not create an empty zone in that case.
- </para>
<para>
- The current list of empty zones is:
- <itemizedlist>
- <listitem>10.IN-ADDR.ARPA</listitem>
- <listitem>16.172.IN-ADDR.ARPA</listitem>
- <listitem>17.172.IN-ADDR.ARPA</listitem>
- <listitem>18.172.IN-ADDR.ARPA</listitem>
- <listitem>19.172.IN-ADDR.ARPA</listitem>
- <listitem>20.172.IN-ADDR.ARPA</listitem>
- <listitem>21.172.IN-ADDR.ARPA</listitem>
- <listitem>22.172.IN-ADDR.ARPA</listitem>
- <listitem>23.172.IN-ADDR.ARPA</listitem>
- <listitem>24.172.IN-ADDR.ARPA</listitem>
- <listitem>25.172.IN-ADDR.ARPA</listitem>
- <listitem>26.172.IN-ADDR.ARPA</listitem>
- <listitem>27.172.IN-ADDR.ARPA</listitem>
- <listitem>28.172.IN-ADDR.ARPA</listitem>
- <listitem>29.172.IN-ADDR.ARPA</listitem>
- <listitem>30.172.IN-ADDR.ARPA</listitem>
- <listitem>31.172.IN-ADDR.ARPA</listitem>
- <listitem>168.192.IN-ADDR.ARPA</listitem>
- <listitem>64.100.IN-ADDR.ARPA</listitem>
- <listitem>65.100.IN-ADDR.ARPA</listitem>
- <listitem>66.100.IN-ADDR.ARPA</listitem>
- <listitem>67.100.IN-ADDR.ARPA</listitem>
- <listitem>68.100.IN-ADDR.ARPA</listitem>
- <listitem>69.100.IN-ADDR.ARPA</listitem>
- <listitem>70.100.IN-ADDR.ARPA</listitem>
- <listitem>71.100.IN-ADDR.ARPA</listitem>
- <listitem>72.100.IN-ADDR.ARPA</listitem>
- <listitem>73.100.IN-ADDR.ARPA</listitem>
- <listitem>74.100.IN-ADDR.ARPA</listitem>
- <listitem>75.100.IN-ADDR.ARPA</listitem>
- <listitem>76.100.IN-ADDR.ARPA</listitem>
- <listitem>77.100.IN-ADDR.ARPA</listitem>
- <listitem>78.100.IN-ADDR.ARPA</listitem>
- <listitem>79.100.IN-ADDR.ARPA</listitem>
- <listitem>80.100.IN-ADDR.ARPA</listitem>
- <listitem>81.100.IN-ADDR.ARPA</listitem>
- <listitem>82.100.IN-ADDR.ARPA</listitem>
- <listitem>83.100.IN-ADDR.ARPA</listitem>
- <listitem>84.100.IN-ADDR.ARPA</listitem>
- <listitem>85.100.IN-ADDR.ARPA</listitem>
- <listitem>86.100.IN-ADDR.ARPA</listitem>
- <listitem>87.100.IN-ADDR.ARPA</listitem>
- <listitem>88.100.IN-ADDR.ARPA</listitem>
- <listitem>89.100.IN-ADDR.ARPA</listitem>
- <listitem>90.100.IN-ADDR.ARPA</listitem>
- <listitem>91.100.IN-ADDR.ARPA</listitem>
- <listitem>92.100.IN-ADDR.ARPA</listitem>
- <listitem>93.100.IN-ADDR.ARPA</listitem>
- <listitem>94.100.IN-ADDR.ARPA</listitem>
- <listitem>95.100.IN-ADDR.ARPA</listitem>
- <listitem>96.100.IN-ADDR.ARPA</listitem>
- <listitem>97.100.IN-ADDR.ARPA</listitem>
- <listitem>98.100.IN-ADDR.ARPA</listitem>
- <listitem>99.100.IN-ADDR.ARPA</listitem>
- <listitem>100.100.IN-ADDR.ARPA</listitem>
- <listitem>101.100.IN-ADDR.ARPA</listitem>
- <listitem>102.100.IN-ADDR.ARPA</listitem>
- <listitem>103.100.IN-ADDR.ARPA</listitem>
- <listitem>104.100.IN-ADDR.ARPA</listitem>
- <listitem>105.100.IN-ADDR.ARPA</listitem>
- <listitem>106.100.IN-ADDR.ARPA</listitem>
- <listitem>107.100.IN-ADDR.ARPA</listitem>
- <listitem>108.100.IN-ADDR.ARPA</listitem>
- <listitem>109.100.IN-ADDR.ARPA</listitem>
- <listitem>110.100.IN-ADDR.ARPA</listitem>
- <listitem>111.100.IN-ADDR.ARPA</listitem>
- <listitem>112.100.IN-ADDR.ARPA</listitem>
- <listitem>113.100.IN-ADDR.ARPA</listitem>
- <listitem>114.100.IN-ADDR.ARPA</listitem>
- <listitem>115.100.IN-ADDR.ARPA</listitem>
- <listitem>116.100.IN-ADDR.ARPA</listitem>
- <listitem>117.100.IN-ADDR.ARPA</listitem>
- <listitem>118.100.IN-ADDR.ARPA</listitem>
- <listitem>119.100.IN-ADDR.ARPA</listitem>
- <listitem>120.100.IN-ADDR.ARPA</listitem>
- <listitem>121.100.IN-ADDR.ARPA</listitem>
- <listitem>122.100.IN-ADDR.ARPA</listitem>
- <listitem>123.100.IN-ADDR.ARPA</listitem>
- <listitem>124.100.IN-ADDR.ARPA</listitem>
- <listitem>125.100.IN-ADDR.ARPA</listitem>
- <listitem>126.100.IN-ADDR.ARPA</listitem>
- <listitem>127.100.IN-ADDR.ARPA</listitem>
- <listitem>0.IN-ADDR.ARPA</listitem>
- <listitem>127.IN-ADDR.ARPA</listitem>
- <listitem>254.169.IN-ADDR.ARPA</listitem>
- <listitem>2.0.192.IN-ADDR.ARPA</listitem>
- <listitem>100.51.198.IN-ADDR.ARPA</listitem>
- <listitem>113.0.203.IN-ADDR.ARPA</listitem>
- <listitem>255.255.255.255.IN-ADDR.ARPA</listitem>
- <listitem>0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.IP6.ARPA</listitem>
- <listitem>1.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.IP6.ARPA</listitem>
- <listitem>8.B.D.0.1.0.0.2.IP6.ARPA</listitem>
- <listitem>D.F.IP6.ARPA</listitem>
- <listitem>8.E.F.IP6.ARPA</listitem>
- <listitem>9.E.F.IP6.ARPA</listitem>
- <listitem>A.E.F.IP6.ARPA</listitem>
- <listitem>B.E.F.IP6.ARPA</listitem>
- </itemizedlist>
+ Forwarding can also be configured on a per-domain basis, allowing
+ for the global forwarding options to be overridden in a variety
+ of ways. You can set particular domains to use different
+ forwarders,
+ or have a different <command>forward only/first</command> behavior,
+ or not forward at all, see <xref linkend="zone_statement_grammar"/>.
</para>
+ </sect3>
+
+ <sect3>
+ <title>Dual-stack Servers</title>
<para>
- Empty zones are settable at the view level and only apply to
- views of class IN. Disabled empty zones are only inherited
- from options if there are no disabled empty zones specified
- at the view level. To override the options list of disabled
- zones, you can disable the root zone at the view level, for example:
-<programlisting>
- disable-empty-zone ".";
-</programlisting>
+ Dual-stack servers are used as servers of last resort to work
+ around
+ problems in reachability due the lack of support for either IPv4
+ or IPv6
+ on the host machine.
</para>
+
+ <variablelist>
+ <varlistentry>
+ <term><command>dual-stack-servers</command></term>
+ <listitem>
+ <para>
+ Specifies host names or addresses of machines with access to
+ both IPv4 and IPv6 transports. If a hostname is used, the
+ server must be able
+ to resolve the name using only the transport it has. If the
+ machine is dual
+ stacked, then the <command>dual-stack-servers</command> have no effect unless
+ access to a transport has been disabled on the command line
+ (e.g. <command>named -4</command>).
+ </para>
+ </listitem>
+ </varlistentry>
+ </variablelist>
+ </sect3>
+
+ <sect3 id="access_control">
+ <title>Access Control</title>
+
<para>
- If you are using the address ranges covered here, you should
- already have reverse zones covering the addresses you use.
- In practice this appears to not be the case with many queries
- being made to the infrastructure servers for names in these
- spaces. So many in fact that sacrificial servers were needed
- to be deployed to channel the query load away from the
- infrastructure servers.
+ Access to the server can be restricted based on the IP address
+ of the requesting system. See <xref linkend="address_match_lists"/> for
+ details on how to specify IP address lists.
</para>
- <note>
- The real parent servers for these zones should disable all
- empty zone under the parent zone they serve. For the real
- root servers, this is all built-in empty zones. This will
- enable them to return referrals to deeper in the tree.
- </note>
- <variablelist>
+
+ <variablelist>
+
<varlistentry>
- <term><command>empty-server</command></term>
+ <term><command>allow-notify</command></term>
<listitem>
- <para>
- Specify what server name will appear in the returned
- SOA record for empty zones. If none is specified, then
- the zone's name will be used.
- </para>
- </listitem>
+ <para>
+ Specifies which hosts are allowed to
+ notify this server, a slave, of zone changes in addition
+ to the zone masters.
+ <command>allow-notify</command> may also be
+ specified in the
+ <command>zone</command> statement, in which case
+ it overrides the
+ <command>options allow-notify</command>
+ statement. It is only meaningful
+ for a slave zone. If not specified, the default is to
+ process notify messages
+ only from a zone's master.
+ </para>
+ </listitem>
</varlistentry>
-
+
<varlistentry>
- <term><command>empty-contact</command></term>
+ <term><command>allow-query</command></term>
<listitem>
- <para>
- Specify what contact name will appear in the returned
- SOA record for empty zones. If none is specified, then
- "." will be used.
- </para>
+ <para>
+ Specifies which hosts are allowed to ask ordinary
+ DNS questions. <command>allow-query</command> may
+ also be specified in the <command>zone</command>
+ statement, in which case it overrides the
+ <command>options allow-query</command> statement.
+ If not specified, the default is to allow queries
+ from all hosts.
+ </para>
+ <note>
+ <para>
+ <command>allow-query-cache</command> is now
+ used to specify access to the cache.
+ </para>
+ </note>
</listitem>
</varlistentry>
-
+
<varlistentry>
- <term><command>empty-zones-enable</command></term>
+ <term><command>allow-query-on</command></term>
<listitem>
- <para>
- Enable or disable all empty zones. By default, they
- are enabled.
- </para>
+ <para>
+ Specifies which local addresses can accept ordinary
+ DNS questions. This makes it possible, for instance,
+ to allow queries on internal-facing interfaces but
+ disallow them on external-facing ones, without
+ necessarily knowing the internal network's addresses.
+ </para>
+ <para>
+ Note that <command>allow-query-on</command> is only
+ checked for queries that are permitted by
+ <command>allow-query</command>. A query must be
+ allowed by both ACLs, or it will be refused.
+ </para>
+ <para>
+ <command>allow-query-on</command> may
+ also be specified in the <command>zone</command>
+ statement, in which case it overrides the
+ <command>options allow-query-on</command> statement.
+ </para>
+ <para>
+ If not specified, the default is to allow queries
+ on all addresses.
+ </para>
+ <note>
+ <para>
+ <command>allow-query-cache</command> is
+ used to specify access to the cache.
+ </para>
+ </note>
</listitem>
</varlistentry>
-
+
<varlistentry>
- <term><command>disable-empty-zone</command></term>
+ <term><command>allow-query-cache</command></term>
<listitem>
- <para>
- Disable individual empty zones. By default, none are
- disabled. This option can be specified multiple times.
- </para>
+ <para>
+ Specifies which hosts are allowed to get answers
+ from the cache. If <command>allow-query-cache</command>
+ is not set then <command>allow-recursion</command>
+ is used if set, otherwise <command>allow-query</command>
+ is used if set unless <command>recursion no;</command> is
+ set in which case <command>none;</command> is used,
+ otherwise the default (<command>localnets;</command>
+ <command>localhost;</command>) is used.
+ </para>
</listitem>
</varlistentry>
- </variablelist>
- </sect3>
-
- <sect3 id="acache">
- <title>Additional Section Caching</title>
-
- <para>
- The additional section cache, also called <command>acache</command>,
- is an internal cache to improve the response performance of BIND 9.
- When additional section caching is enabled, BIND 9 will
- cache an internal short-cut to the additional section content for
- each answer RR.
- Note that <command>acache</command> is an internal caching
- mechanism of BIND 9, and is not related to the DNS caching
- server function.
- </para>
-
- <para>
- Additional section caching does not change the
- response content (except the RRsets ordering of the additional
- section, see below), but can improve the response performance
- significantly.
- It is particularly effective when BIND 9 acts as an authoritative
- server for a zone that has many delegations with many glue RRs.
- </para>
-
- <para>
- In order to obtain the maximum performance improvement
- from additional section caching, setting
- <command>additional-from-cache</command>
- to <command>no</command> is recommended, since the current
- implementation of <command>acache</command>
- does not short-cut of additional section information from the
- DNS cache data.
- </para>
-
- <para>
- One obvious disadvantage of <command>acache</command> is
- that it requires much more
- memory for the internal cached data.
- Thus, if the response performance does not matter and memory
- consumption is much more critical, the
- <command>acache</command> mechanism can be
- disabled by setting <command>acache-enable</command> to
- <command>no</command>.
- It is also possible to specify the upper limit of memory
- consumption
- for acache by using <command>max-acache-size</command>.
- </para>
-
- <para>
- Additional section caching also has a minor effect on the
- RRset ordering in the additional section.
- Without <command>acache</command>,
- <command>cyclic</command> order is effective for the additional
- section as well as the answer and authority sections.
- However, additional section caching fixes the ordering when it
- first caches an RRset for the additional section, and the same
- ordering will be kept in succeeding responses, regardless of the
- setting of <command>rrset-order</command>.
- The effect of this should be minor, however, since an
- RRset in the additional section
- typically only contains a small number of RRs (and in many cases
- it only contains a single RR), in which case the
- ordering does not matter much.
- </para>
-
- <para>
- The following is a summary of options related to
- <command>acache</command>.
- </para>
-
- <variablelist>
-
- <varlistentry>
- <term><command>acache-enable</command></term>
- <listitem>
- <para>
- If <command>yes</command>, additional section caching is
- enabled. The default value is <command>no</command>.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>acache-cleaning-interval</command></term>
- <listitem>
- <para>
- The server will remove stale cache entries, based on an LRU
- based
- algorithm, every <command>acache-cleaning-interval</command> minutes.
- The default is 60 minutes.
- If set to 0, no periodic cleaning will occur.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>max-acache-size</command></term>
- <listitem>
- <para>
- The maximum amount of memory in bytes to use for the server's acache.
- When the amount of data in the acache reaches this limit,
- the server
- will clean more aggressively so that the limit is not
- exceeded.
- In a server with multiple views, the limit applies
- separately to the
- acache of each view.
- The default is <literal>16M</literal>.
- </para>
- </listitem>
- </varlistentry>
-
- </variablelist>
-
- </sect3>
-
- <sect3>
- <title>Content Filtering</title>
- <para>
- <acronym>BIND</acronym> 9 provides the ability to filter
- out DNS responses from external DNS servers containing
- certain types of data in the answer section.
- Specifically, it can reject address (A or AAAA) records if
- the corresponding IPv4 or IPv6 addresses match the given
- <varname>address_match_list</varname> of the
- <command>deny-answer-addresses</command> option.
- It can also reject CNAME or DNAME records if the "alias"
- name (i.e., the CNAME alias or the substituted query name
- due to DNAME) matches the
- given <varname>namelist</varname> of the
- <command>deny-answer-aliases</command> option, where
- "match" means the alias name is a subdomain of one of
- the <varname>name_list</varname> elements.
- If the optional <varname>namelist</varname> is specified
- with <command>except-from</command>, records whose query name
- matches the list will be accepted regardless of the filter
- setting.
- Likewise, if the alias name is a subdomain of the
- corresponding zone, the <command>deny-answer-aliases</command>
- filter will not apply;
- for example, even if "example.com" is specified for
- <command>deny-answer-aliases</command>,
- </para>
-<programlisting>www.example.com. CNAME xxx.example.com.</programlisting>
+ <varlistentry>
+ <term><command>allow-query-cache-on</command></term>
+ <listitem>
+ <para>
+ Specifies which local addresses can give answers
+ from the cache. If not specified, the default is
+ to allow cache queries on any address,
+ <command>localnets</command> and
+ <command>localhost</command>.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>allow-recursion</command></term>
+ <listitem>
+ <para>
+ Specifies which hosts are allowed to make recursive
+ queries through this server. If
+ <command>allow-recursion</command> is not set
+ then <command>allow-query-cache</command> is
+ used if set, otherwise <command>allow-query</command>
+ is used if set, otherwise the default
+ (<command>localnets;</command>
+ <command>localhost;</command>) is used.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>allow-recursion-on</command></term>
+ <listitem>
+ <para>
+ Specifies which local addresses can accept recursive
+ queries. If not specified, the default is to allow
+ recursive queries on all addresses.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>allow-update</command></term>
+ <listitem>
+ <para>
+ Specifies which hosts are allowed to
+ submit Dynamic DNS updates for master zones. The default is
+ to deny
+ updates from all hosts. Note that allowing updates based
+ on the requestor's IP address is insecure; see
+ <xref linkend="dynamic_update_security"/> for details.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>allow-update-forwarding</command></term>
+ <listitem>
+ <para>
+ Specifies which hosts are allowed to
+ submit Dynamic DNS updates to slave zones to be forwarded to
+ the
+ master. The default is <userinput>{ none; }</userinput>,
+ which
+ means that no update forwarding will be performed. To
+ enable
+ update forwarding, specify
+ <userinput>allow-update-forwarding { any; };</userinput>.
+ Specifying values other than <userinput>{ none; }</userinput> or
+ <userinput>{ any; }</userinput> is usually
+ counterproductive, since
+ the responsibility for update access control should rest
+ with the
+ master server, not the slaves.
+ </para>
+ <para>
+ Note that enabling the update forwarding feature on a slave
+ server
+ may expose master servers relying on insecure IP address
+ based
+ access control to attacks; see <xref linkend="dynamic_update_security"/>
+ for more details.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>allow-v6-synthesis</command></term>
+ <listitem>
+ <para>
+ This option was introduced for the smooth transition from
+ AAAA
+ to A6 and from "nibble labels" to binary labels.
+ However, since both A6 and binary labels were then
+ deprecated,
+ this option was also deprecated.
+ It is now ignored with some warning messages.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>allow-transfer</command></term>
+ <listitem>
+ <para>
+ Specifies which hosts are allowed to
+ receive zone transfers from the server. <command>allow-transfer</command> may
+ also be specified in the <command>zone</command>
+ statement, in which
+ case it overrides the <command>options allow-transfer</command> statement.
+ If not specified, the default is to allow transfers to all
+ hosts.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>blackhole</command></term>
+ <listitem>
+ <para>
+ Specifies a list of addresses that the
+ server will not accept queries from or use to resolve a
+ query. Queries
+ from these addresses will not be responded to. The default
+ is <userinput>none</userinput>.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>filter-aaaa</command></term>
+ <listitem>
+ <para>
+ Specifies a list of addresses to which
+ <command>filter-aaaa-on-v4</command>
+ is applies. The default is <userinput>any</userinput>.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>resolver-query-timeout</command></term>
+ <listitem>
+ <para>
+ The amount of time the resolver will spend attempting
+ to resolve a recursive query before failing. The default
+ and minimum is <literal>10</literal> and the maximum is
+ <literal>30</literal>. Setting it to <literal>0</literal>
+ will result in the default being used.
+ </para>
+ </listitem>
+ </varlistentry>
+ </variablelist>
+
+ </sect3>
+
+ <sect3>
+ <title>Interfaces</title>
<para>
- returned by an "example.com" server will be accepted.
+ The interfaces and ports that the server will answer queries
+ from may be specified using the <command>listen-on</command> option. <command>listen-on</command> takes
+ an optional port and an <varname>address_match_list</varname>.
+ The server will listen on all interfaces allowed by the address
+ match list. If a port is not specified, port 53 will be used.
+ </para>
+ <para>
+ Multiple <command>listen-on</command> statements are
+ allowed.
+ For example,
</para>
+<programlisting>listen-on { 5.6.7.8; };
+listen-on port 1234 { !1.2.3.4; 1.2/16; };
+</programlisting>
+
<para>
- In the <varname>address_match_list</varname> of the
- <command>deny-answer-addresses</command> option, only
- <varname>ip_addr</varname>
- and <varname>ip_prefix</varname>
- are meaningful;
- any <varname>key_id</varname> will be silently ignored.
+ will enable the name server on port 53 for the IP address
+ 5.6.7.8, and on port 1234 of an address on the machine in net
+ 1.2 that is not 1.2.3.4.
</para>
<para>
- If a response message is rejected due to the filtering,
- the entire message is discarded without being cached, and
- a SERVFAIL error will be returned to the client.
+ If no <command>listen-on</command> is specified, the
+ server will listen on port 53 on all IPv4 interfaces.
</para>
<para>
- This filtering is intended to prevent "DNS rebinding attacks," in
- which an attacker, in response to a query for a domain name the
- attacker controls, returns an IP address within your own network or
- an alias name within your own domain.
- A naive web browser or script could then serve as an
- unintended proxy, allowing the attacker
- to get access to an internal node of your local network
- that couldn't be externally accessed otherwise.
- See the paper available at
- <ulink url="http://portal.acm.org/citation.cfm?id=1315245.1315298">
- http://portal.acm.org/citation.cfm?id=1315245.1315298
- </ulink>
- for more details about the attacks.
+ The <command>listen-on-v6</command> option is used to
+ specify the interfaces and the ports on which the server will
+ listen for incoming queries sent using IPv6. If not specified,
+ the server will listen on port 53 on all IPv6 interfaces.
</para>
<para>
- For example, if you own a domain named "example.net" and
- your internal network uses an IPv4 prefix 192.0.2.0/24,
- you might specify the following rules:
+ When <programlisting>{ any; }</programlisting> is
+ specified
+ as the <varname>address_match_list</varname> for the
+ <command>listen-on-v6</command> option,
+ the server does not bind a separate socket to each IPv6 interface
+ address as it does for IPv4 if the operating system has enough API
+ support for IPv6 (specifically if it conforms to RFC 3493 and RFC
+ 3542).
+ Instead, it listens on the IPv6 wildcard address.
+ If the system only has incomplete API support for IPv6, however,
+ the behavior is the same as that for IPv4.
</para>
-<programlisting>deny-answer-addresses { 192.0.2.0/24; } except-from { "example.net"; };
-deny-answer-aliases { "example.net"; };
-</programlisting>
+ <para>
+ A list of particular IPv6 addresses can also be specified, in
+ which case
+ the server listens on a separate socket for each specified
+ address,
+ regardless of whether the desired API is supported by the system.
+ </para>
<para>
- If an external attacker lets a web browser in your local
- network look up an IPv4 address of "attacker.example.com",
- the attacker's DNS server would return a response like this:
+ Multiple <command>listen-on-v6</command> options can
+ be used.
+ For example,
</para>
-<programlisting>attacker.example.com. A 192.0.2.1</programlisting>
+<programlisting>listen-on-v6 { any; };
+listen-on-v6 port 1234 { !2001:db8::/32; any; };
+</programlisting>
<para>
- in the answer section.
- Since the rdata of this record (the IPv4 address) matches
- the specified prefix 192.0.2.0/24, this response will be
- ignored.
+ will enable the name server on port 53 for any IPv6 addresses
+ (with a single wildcard socket),
+ and on port 1234 of IPv6 addresses that is not in the prefix
+ 2001:db8::/32 (with separate sockets for each matched address.)
</para>
<para>
- On the other hand, if the browser looks up a legitimate
- internal web server "www.example.net" and the
- following response is returned to
- the <acronym>BIND</acronym> 9 server
+ To make the server not listen on any IPv6 address, use
</para>
-<programlisting>www.example.net. A 192.0.2.2</programlisting>
+<programlisting>listen-on-v6 { none; };
+</programlisting>
+
+ </sect3>
+ <sect3 id="query_address">
+ <title>Query Address</title>
<para>
- it will be accepted since the owner name "www.example.net"
- matches the <command>except-from</command> element,
- "example.net".
+ If the server doesn't know the answer to a question, it will
+ query other name servers. <command>query-source</command> specifies
+ the address and port used for such queries. For queries sent over
+ IPv6, there is a separate <command>query-source-v6</command> option.
+ If <command>address</command> is <command>*</command> (asterisk) or is omitted,
+ a wildcard IP address (<command>INADDR_ANY</command>)
+ will be used.
</para>
<para>
- Note that this is not really an attack on the DNS per se.
- In fact, there is nothing wrong for an "external" name to
- be mapped to your "internal" IP address or domain name
- from the DNS point of view.
- It might actually be provided for a legitimate purpose,
- such as for debugging.
- As long as the mapping is provided by the correct owner,
- it is not possible or does not make sense to detect
- whether the intent of the mapping is legitimate or not
- within the DNS.
- The "rebinding" attack must primarily be protected at the
- application that uses the DNS.
- For a large site, however, it may be difficult to protect
- all possible applications at once.
- This filtering feature is provided only to help such an
- operational environment;
- it is generally discouraged to turn it on unless you are
- very sure you have no other choice and the attack is a
- real threat for your applications.
+ If <command>port</command> is <command>*</command> or is omitted,
+ a random port number from a pre-configured
+ range is picked up and will be used for each query.
+ The port range(s) is that specified in
+ the <command>use-v4-udp-ports</command> (for IPv4)
+ and <command>use-v6-udp-ports</command> (for IPv6)
+ options, excluding the ranges specified in
+ the <command>avoid-v4-udp-ports</command>
+ and <command>avoid-v6-udp-ports</command> options, respectively.
</para>
<para>
- Care should be particularly taken if you want to use this
- option for addresses within 127.0.0.0/8.
- These addresses are obviously "internal", but many
- applications conventionally rely on a DNS mapping from
- some name to such an address.
- Filtering out DNS records containing this address
- spuriously can break such applications.
+ The defaults of the <command>query-source</command> and
+ <command>query-source-v6</command> options
+ are:
</para>
- </sect3>
- <sect3>
- <title>Response Policy Zone (RPZ) Rewriting</title>
+<programlisting>query-source address * port *;
+query-source-v6 address * port *;
+</programlisting>
+
<para>
- <acronym>BIND</acronym> 9 includes a limited
- mechanism to modify DNS responses for requests
- analogous to email anti-spam DNS blacklists.
- Responses can be changed to deny the existence of domains(NXDOMAIN),
- deny the existence of IP addresses for domains (NODATA),
- or contain other IP addresses or data.
+ If <command>use-v4-udp-ports</command> or
+ <command>use-v6-udp-ports</command> is unspecified,
+ <command>named</command> will check if the operating
+ system provides a programming interface to retrieve the
+ system's default range for ephemeral ports.
+ If such an interface is available,
+ <command>named</command> will use the corresponding system
+ default range; otherwise, it will use its own defaults:
+ </para>
+
+<programlisting>use-v4-udp-ports { range 1024 65535; };
+use-v6-udp-ports { range 1024 65535; };
+</programlisting>
+
+ <para>
+ Note: make sure the ranges be sufficiently large for
+ security. A desirable size depends on various parameters,
+ but we generally recommend it contain at least 16384 ports
+ (14 bits of entropy).
+ Note also that the system's default range when used may be
+ too small for this purpose, and that the range may even be
+ changed while <command>named</command> is running; the new
+ range will automatically be applied when <command>named</command>
+ is reloaded.
+ It is encouraged to
+ configure <command>use-v4-udp-ports</command> and
+ <command>use-v6-udp-ports</command> explicitly so that the
+ ranges are sufficiently large and are reasonably
+ independent from the ranges used by other applications.
</para>
<para>
- Response policy zones are named in the
- <command>response-policy</command> option for the view or among the
- global options if there is no response-policy option for the view.
- Response policy zones are ordinary DNS zones containing RRsets
- that can be queried normally if allowed.
- It is usually best to restrict those queries with something like
- <command>allow-query { localhost; };</command>.
+ Note: the operational configuration
+ where <command>named</command> runs may prohibit the use
+ of some ports. For example, UNIX systems will not allow
+ <command>named</command> running without a root privilege
+ to use ports less than 1024.
+ If such ports are included in the specified (or detected)
+ set of query ports, the corresponding query attempts will
+ fail, resulting in resolution failures or delay.
+ It is therefore important to configure the set of ports
+ that can be safely used in the expected operational environment.
</para>
<para>
- Five policy triggers can be encoded in RPZ records.
- <variablelist>
- <varlistentry>
- <term><command>RPZ-CLIENT-IP</command></term>
- <listitem>
- <para>
- IP records are triggered by the IP address of the
- DNS client.
- Client IP address triggers are encoded in records that have
- owner names that are subdomains of
- <command>rpz-client-ip</command> relativized to the
- policy zone origin name
- and encode an address or address block.
- IPv4 addresses are represented as
- <userinput>prefixlength.B4.B3.B2.B1.rpz-ip</userinput>.
- The IPv4 prefix length must be between 1 and 32.
- All four bytes, B4, B3, B2, and B1, must be present.
- B4 is the decimal value of the least significant byte of the
- IPv4 address as in IN-ADDR.ARPA.
- </para>
-
- <para>
- IPv6 addresses are encoded in a format similar
- to the standard IPv6 text representation,
- <userinput>prefixlength.W8.W7.W6.W5.W4.W3.W2.W1.rpz-ip</userinput>.
- Each of W8,...,W1 is a one to four digit hexadecimal number
- representing 16 bits of the IPv6 address as in the standard
- text representation of IPv6 addresses,
- but reversed as in IN-ADDR.ARPA.
- All 8 words must be present except when one set of consecutive
- zero words is replaced with <userinput>.zz.</userinput>
- analogous to double colons (::) in standard IPv6 text
- encodings.
- The IPv6 prefix length must be between 64 and 128.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>QNAME</command></term>
- <listitem>
- <para>
- QNAME policy records are triggered by query names of
- requests and targets of CNAME records resolved to generate
- the response.
- The owner name of a QNAME policy record is
- the query name relativized to the policy zone.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>RPZ-IP</command></term>
- <listitem>
- <para>
- IP triggers are IP addresses in an
- A or AAAA record in the ANSWER section of a response.
- They are encoded like client-IP triggers except as
- subdomains of <command>rpz-ip</command>.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>RPZ-NSDNAME</command></term>
- <listitem>
- <para>
- NSDNAME triggers match names of authoritative servers
- for the query name, a parent of the query name, a CNAME for
- query name, or a parent of a CNAME.
- They are encoded as subdomains of
- <command>rpz-nsdname</command> relativized
- to the RPZ origin name.
- NSIP triggers match IP addresses in A and
- AAAA RRsets for domains that can be checked against NSDNAME
- policy records.
- </para>
- </listitem>
- </varlistentry>
+ The defaults of the <command>avoid-v4-udp-ports</command> and
+ <command>avoid-v6-udp-ports</command> options
+ are:
+ </para>
- <varlistentry>
- <term><command>RPZ-NSIP</command></term>
- <listitem>
- <para>
- NSIP triggers are encoded like IP triggers except as
- subdomains of <command>rpz-nsip</command>.
- NSDNAME and NSIP triggers are checked only for names with at
- least <command>min-ns-dots</command> dots.
- The default value of <command>min-ns-dots</command> is 1 to
- exclude top level domains.
- </para>
- </listitem>
- </varlistentry>
- </variablelist>
- </para>
+<programlisting>avoid-v4-udp-ports {};
+avoid-v6-udp-ports {};
+</programlisting>
<para>
- The query response is checked against all response policy zones,
- so two or more policy records can be triggered by a response.
- Because DNS responses are rewritten according to at most one
- policy record, a single record encoding an action (other than
- <command>DISABLED</command> actions) must be chosen.
- Triggers or the records that encode them are chosen for the
- rewriting in the following order:
- <itemizedlist>
- <listitem>Choose the triggered record in the zone that appears
- first in the <command>response-policy</command> option.
- </listitem>
- <listitem>Prefer CLIENT-IP to QNAME to IP to NSDNAME to NSIP
- triggers in a single zone.
- </listitem>
- <listitem>Among NSDNAME triggers, prefer the
- trigger that matches the smallest name under the DNSSEC ordering.
+ Note: BIND 9.5.0 introduced
+ the <command>use-queryport-pool</command>
+ option to support a pool of such random ports, but this
+ option is now obsolete because reusing the same ports in
+ the pool may not be sufficiently secure.
+ For the same reason, it is generally strongly discouraged to
+ specify a particular port for the
+ <command>query-source</command> or
+ <command>query-source-v6</command> options;
+ it implicitly disables the use of randomized port numbers.
+ </para>
+
+ <variablelist>
+ <varlistentry>
+ <term><command>use-queryport-pool</command></term>
+ <listitem>
+ <para>
+ This option is obsolete.
+ </para>
</listitem>
- <listitem>Among IP or NSIP triggers, prefer the trigger
- with the longest prefix.
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>queryport-pool-ports</command></term>
+ <listitem>
+ <para>
+ This option is obsolete.
+ </para>
</listitem>
- <listitem>Among triggers with the same prefex length,
- prefer the IP or NSIP trigger that matches
- the smallest IP address.
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>queryport-pool-updateinterval</command></term>
+ <listitem>
+ <para>
+ This option is obsolete.
+ </para>
</listitem>
- </itemizedlist>
- </para>
+ </varlistentry>
+
+ </variablelist>
+ <note>
+ <para>
+ The address specified in the <command>query-source</command> option
+ is used for both UDP and TCP queries, but the port applies only
+ to UDP queries. TCP queries always use a random
+ unprivileged port.
+ </para>
+ </note>
+ <note>
+ <para>
+ Solaris 2.5.1 and earlier does not support setting the source
+ address for TCP sockets.
+ </para>
+ </note>
+ <note>
+ <para>
+ See also <command>transfer-source</command> and
+ <command>notify-source</command>.
+ </para>
+ </note>
+ </sect3>
+ <sect3 id="zone_transfers">
+ <title>Zone Transfers</title>
<para>
- When the processing of a response is restarted to resolve
- DNAME or CNAME records and a policy record set has
- not been triggered,
- all response policy zones are again consulted for the
- DNAME or CNAME names and addresses.
+ <acronym>BIND</acronym> has mechanisms in place to
+ facilitate zone transfers
+ and set limits on the amount of load that transfers place on the
+ system. The following options apply to zone transfers.
</para>
- <para>
- RPZ record sets are any types of DNS record except
- DNAME or DNSSEC that encode actions or responses to
- individual queries.
- Any of the policies can be used with any of the triggers.
- For example, while the <command>TCP-only</command> policy is
- commonly used with <command>client-IP</command> triggers,
- it cn be used with any type of trigger to force the use of
- TCP for responses with owner names in a zone.
- <variablelist>
- <varlistentry>
- <term><command>PASSTHRU</command></term>
- <listitem>
- <para>
- The whitelist policy is specified
- by a CNAME whose target is <command>rpz-passthru</command>.
- It causes the response to not be rewritten
- and is most often used to "poke holes" in policies for
- CIDR blocks.
- </para>
- </listitem>
- </varlistentry>
+ <variablelist>
- <varlistentry>
- <term><command>DROP</command></term>
- <listitem>
- <para>
- The blacklist policy is specified
- by a CNAME whose target is <command>rpz-drop</command>.
- It causes the response to be discarded.
- Nothing is sent to the DNS client.
- </para>
- </listitem>
- </varlistentry>
+ <varlistentry>
+ <term><command>also-notify</command></term>
+ <listitem>
+ <para>
+ Defines a global list of IP addresses of name servers
+ that are also sent NOTIFY messages whenever a fresh copy of
+ the
+ zone is loaded, in addition to the servers listed in the
+ zone's NS records.
+ This helps to ensure that copies of the zones will
+ quickly converge on stealth servers.
+ Optionally, a port may be specified with each
+ <command>also-notify</command> address to send
+ the notify messages to a port other than the
+ default of 53.
+ An optional TSIG key can also be specified with each
+ address to cause the notify messages to be signed; this
+ can be useful when sending notifies to multiple views.
+ In place of explicit addresses, one or more named
+ <command>masters</command> lists can be used.
+ </para>
+ <para>
+ If an <command>also-notify</command> list
+ is given in a <command>zone</command> statement,
+ it will override
+ the <command>options also-notify</command>
+ statement. When a <command>zone notify</command>
+ statement
+ is set to <command>no</command>, the IP
+ addresses in the global <command>also-notify</command> list will
+ not be sent NOTIFY messages for that zone. The default is
+ the empty
+ list (no global notification list).
+ </para>
+ </listitem>
+ </varlistentry>
- <varlistentry>
- <term><command>TCP-Only</command></term>
- <listitem>
- <para>
- The "slip" policy is specified
- by a CNAME whose target is <command>rpz-tcp-only</command>.
- It changes UDP responses to short, truncated DNS responses
- that require the DNS client to try again with TCP.
- It is used to mitigate distributed DNS reflection attacks.
- </para>
- </listitem>
- </varlistentry>
+ <varlistentry>
+ <term><command>max-transfer-time-in</command></term>
+ <listitem>
+ <para>
+ Inbound zone transfers running longer than
+ this many minutes will be terminated. The default is 120
+ minutes
+ (2 hours). The maximum value is 28 days (40320 minutes).
+ </para>
+ </listitem>
+ </varlistentry>
- <varlistentry>
- <term><command>NXDOMAIN</command></term>
- <listitem>
- <para>
- The domain undefined response is encoded
- by a CNAME whose target is the root domain (.)
- </para>
- </listitem>
- </varlistentry>
+ <varlistentry>
+ <term><command>max-transfer-idle-in</command></term>
+ <listitem>
+ <para>
+ Inbound zone transfers making no progress
+ in this many minutes will be terminated. The default is 60
+ minutes
+ (1 hour). The maximum value is 28 days (40320 minutes).
+ </para>
+ </listitem>
+ </varlistentry>
- <varlistentry>
- <term><command>NODATA</command></term>
- <listitem>
- The empty set of resource records is specified by
- CNAME whose target is the wildcard top-level
- domain (*.).
- It rewrites the response to NODATA or ANCOUNT=1.
- </para>
- </listitem>
- </varlistentry>
+ <varlistentry>
+ <term><command>max-transfer-time-out</command></term>
+ <listitem>
+ <para>
+ Outbound zone transfers running longer than
+ this many minutes will be terminated. The default is 120
+ minutes
+ (2 hours). The maximum value is 28 days (40320 minutes).
+ </para>
+ </listitem>
+ </varlistentry>
- <varlistentry>
- <term><command>Local Data</command></term>
- <listitem>
- <para>
- A set of ordinary DNS records can be used to answer queries.
- Queries for record types not the set are answered with
- NODATA.
- </para>
+ <varlistentry>
+ <term><command>max-transfer-idle-out</command></term>
+ <listitem>
+ <para>
+ Outbound zone transfers making no progress
+ in this many minutes will be terminated. The default is 60
+ minutes (1
+ hour). The maximum value is 28 days (40320 minutes).
+ </para>
+ </listitem>
+ </varlistentry>
- <para>
- A special form of local data is a CNAME whose target is a
- wildcard such as *.example.com.
- It is used as if were an ordinary CNAME after the astrisk (*)
- has been replaced with the query name.
- The purpose for this special form is query logging in the
- walled garden's authority DNS server.
- </para>
- </listitem>
- </varlistentry>
- </variablelist>
- </para>
+ <varlistentry>
+ <term><command>serial-query-rate</command></term>
+ <listitem>
+ <para>
+ Slave servers will periodically query master
+ servers to find out if zone serial numbers have
+ changed. Each such query uses a minute amount of
+ the slave server's network bandwidth. To limit
+ the amount of bandwidth used, BIND 9 limits the
+ rate at which queries are sent. The value of the
+ <command>serial-query-rate</command> option, an
+ integer, is the maximum number of queries sent
+ per second. The default is 20.
+ </para>
+ <para>
+ In addition to controlling the rate SOA refresh
+ queries are issued at
+ <command>serial-query-rate</command> also controls
+ the rate at which NOTIFY messages are sent from
+ both master and slave zones.
+ </para>
+ </listitem>
+ </varlistentry>
- <para>
- All of the actions specified in all of the individual records
- in a policy zone
- can be overridden with a <command>policy</command> clause in the
- <command>response-policy</command> option.
- An organization using a policy zone provided by another
- organization might use this mechanism to redirect domains
- to its own walled garden.
- <variablelist>
- <varlistentry>
- <term><command>GIVEN</command></term>
- <listitem>
- <para>The placeholder policy says "do not override but
- perform the action specified in the zone."
- </para>
- </listitem>
- </varlistentry>
+ <varlistentry>
+ <term><command>serial-queries</command></term>
+ <listitem>
+ <para>
+ In BIND 8, the <command>serial-queries</command>
+ option
+ set the maximum number of concurrent serial number queries
+ allowed to be outstanding at any given time.
+ BIND 9 does not limit the number of outstanding
+ serial queries and ignores the <command>serial-queries</command> option.
+ Instead, it limits the rate at which the queries are sent
+ as defined using the <command>serial-query-rate</command> option.
+ </para>
+ </listitem>
+ </varlistentry>
- <varlistentry>
- <term><command>DISABLED</command></term>
- <listitem>
+ <varlistentry>
+ <term><command>transfer-format</command></term>
+ <listitem>
+
+ <para>
+ Zone transfers can be sent using two different formats,
+ <command>one-answer</command> and
+ <command>many-answers</command>.
+ The <command>transfer-format</command> option is used
+ on the master server to determine which format it sends.
+ <command>one-answer</command> uses one DNS message per
+ resource record transferred.
+ <command>many-answers</command> packs as many resource
+ records as possible into a message.
+ <command>many-answers</command> is more efficient, but is
+ only supported by relatively new slave servers,
+ such as <acronym>BIND</acronym> 9, <acronym>BIND</acronym>
+ 8.x and <acronym>BIND</acronym> 4.9.5 onwards.
+ The <command>many-answers</command> format is also supported by
+ recent Microsoft Windows nameservers.
+ The default is <command>many-answers</command>.
+ <command>transfer-format</command> may be overridden on a
+ per-server basis by using the <command>server</command>
+ statement.
+ </para>
+
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>transfers-in</command></term>
+ <listitem>
+ <para>
+ The maximum number of inbound zone transfers
+ that can be running concurrently. The default value is <literal>10</literal>.
+ Increasing <command>transfers-in</command> may
+ speed up the convergence
+ of slave zones, but it also may increase the load on the
+ local system.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>transfers-out</command></term>
+ <listitem>
+ <para>
+ The maximum number of outbound zone transfers
+ that can be running concurrently. Zone transfer requests in
+ excess
+ of the limit will be refused. The default value is <literal>10</literal>.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>transfers-per-ns</command></term>
+ <listitem>
+ <para>
+ The maximum number of inbound zone transfers
+ that can be concurrently transferring from a given remote
+ name server.
+ The default value is <literal>2</literal>.
+ Increasing <command>transfers-per-ns</command>
+ may
+ speed up the convergence of slave zones, but it also may
+ increase
+ the load on the remote name server. <command>transfers-per-ns</command> may
+ be overridden on a per-server basis by using the <command>transfers</command> phrase
+ of the <command>server</command> statement.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>transfer-source</command></term>
+ <listitem>
+ <para><command>transfer-source</command>
+ determines which local address will be bound to IPv4
+ TCP connections used to fetch zones transferred
+ inbound by the server. It also determines the
+ source IPv4 address, and optionally the UDP port,
+ used for the refresh queries and forwarded dynamic
+ updates. If not set, it defaults to a system
+ controlled value which will usually be the address
+ of the interface "closest to" the remote end. This
+ address must appear in the remote end's
+ <command>allow-transfer</command> option for the
+ zone being transferred, if one is specified. This
+ statement sets the
+ <command>transfer-source</command> for all zones,
+ but can be overridden on a per-view or per-zone
+ basis by including a
+ <command>transfer-source</command> statement within
+ the <command>view</command> or
+ <command>zone</command> block in the configuration
+ file.
+ </para>
+ <note>
<para>
- The testing override policy causes policy zone records to do
- nothing but log what they would have done if the
- policy zone were not disabled.
- The response to the DNS query will be written (or not)
- according to any triggered policy records that are not
- disabled.
- Disabled policy zones should appear first,
- because they will often not be logged
- if a higher precedence trigger is found first.
+ Solaris 2.5.1 and earlier does not support setting the
+ source address for TCP sockets.
</para>
- </listitem>
- </varlistentry>
+ </note>
+ </listitem>
+ </varlistentry>
- <varlistentry>
- <term><command>PASSTHRU</command></term>,
- <term><command>DROP</command></term>,
- <term><command>TCP-Only</command></term>,
- <term><command>NXDOMAIN</command></term>,
- and
- <term><command>NODATA</command></term>
- <listitem>
+ <varlistentry>
+ <term><command>transfer-source-v6</command></term>
+ <listitem>
+ <para>
+ The same as <command>transfer-source</command>,
+ except zone transfers are performed using IPv6.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>alt-transfer-source</command></term>
+ <listitem>
+ <para>
+ An alternate transfer source if the one listed in
+ <command>transfer-source</command> fails and
+ <command>use-alt-transfer-source</command> is
+ set.
+ </para>
+ <note>
+ If you do not wish the alternate transfer source
+ to be used, you should set
+ <command>use-alt-transfer-source</command>
+ appropriately and you should not depend upon
+ getting an answer back to the first refresh
+ query.
+ </note>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>alt-transfer-source-v6</command></term>
+ <listitem>
+ <para>
+ An alternate transfer source if the one listed in
+ <command>transfer-source-v6</command> fails and
+ <command>use-alt-transfer-source</command> is
+ set.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>use-alt-transfer-source</command></term>
+ <listitem>
+ <para>
+ Use the alternate transfer sources or not. If views are
+ specified this defaults to <command>no</command>
+ otherwise it defaults to
+ <command>yes</command> (for BIND 8
+ compatibility).
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>notify-source</command></term>
+ <listitem>
+ <para><command>notify-source</command>
+ determines which local source address, and
+ optionally UDP port, will be used to send NOTIFY
+ messages. This address must appear in the slave
+ server's <command>masters</command> zone clause or
+ in an <command>allow-notify</command> clause. This
+ statement sets the <command>notify-source</command>
+ for all zones, but can be overridden on a per-zone or
+ per-view basis by including a
+ <command>notify-source</command> statement within
+ the <command>zone</command> or
+ <command>view</command> block in the configuration
+ file.
+ </para>
+ <note>
<para>
- override with the corresponding per-record policy.
+ Solaris 2.5.1 and earlier does not support setting the
+ source address for TCP sockets.
</para>
- </listitem>
- </varlistentry>
+ </note>
+ </listitem>
+ </varlistentry>
- <varlistentry>
- <term><command>CNAME domain</command></term>
- <listitem>
- <para>
- causes all RPZ policy records to act as if they were
- "cname domain" records.
- </para>
- </listitem>
- </varlistentry>
- </variablelist>
- </para>
+ <varlistentry>
+ <term><command>notify-source-v6</command></term>
+ <listitem>
+ <para>
+ Like <command>notify-source</command>,
+ but applies to notify messages sent to IPv6 addresses.
+ </para>
+ </listitem>
+ </varlistentry>
- <para>
- By default, the actions encoded in a response policy zone
- are applied only to queries that ask for recursion (RD=1).
- That default can be changed for a single policy zone or
- all response policy zones in a view
- with a <command>recursive-only no</command> clause.
- This feature is useful for serving the same zone files
- both inside and outside an RFC 1918 cloud and using RPZ to
- delete answers that would otherwise contain RFC 1918 values
- on the externally visible name server or view.
- </para>
+ </variablelist>
- <para>
- Also by default, RPZ actions are applied only to DNS requests
- that either do not request DNSSEC metadata (DO=0) or when no
- DNSSEC records are available for request name in the original
- zone (not the response policy zone). This default can be
- changed for all response policy zones in a view with a
- <command>break-dnssec yes</command> clause. In that case, RPZ
- actions are applied regardless of DNSSEC. The name of the
- clause option reflects the fact that results rewritten by RPZ
- actions cannot verify.
- </para>
+ </sect3>
+ <sect3>
+ <title>UDP Port Lists</title>
<para>
- No DNS records are needed for a QNAME or Client-IP trigger.
- The name or IP address itself is sufficient,
- so in principle the query name need not be recursively resolved.
- However, not resolving the requested
- name can leak the fact that response policy rewriting is in use
- and that the name is listed in a policy zone to operators of
- servers for listed names. To prevent that information leak, by
- default any recursion needed for a request is done before any
- policy triggers are considered. Because listed domains often
- have slow authoritative servers, this default behavior can cost
- significant time.
- The <command>qname-wait-recurse no</command> option
- overrides that default behavior when recursion cannot
- change a non-error response.
- The option does not affect QNAME or client-IP triggers
- in policy zones listed
- after other zones containing IP, NSIP and NSDNAME triggers, because
- those may depend on the A, AAAA, and NS records that would be
- found during recursive resolution. It also does not affect
- DNSSEC requests (DO=1) unless <command>break-dnssec yes</command>
- is in use, because the response would depend on whether or not
- RRSIG records were found during resolution.
- The option can cause appear to rewrite error responses
- such as SERVFAIL when no recursion is done to discover problems
- at the authoritative server.
+ <command>use-v4-udp-ports</command>,
+ <command>avoid-v4-udp-ports</command>,
+ <command>use-v6-udp-ports</command>, and
+ <command>avoid-v6-udp-ports</command>
+ specify a list of IPv4 and IPv6 UDP ports that will be
+ used or not used as source ports for UDP messages.
+ See <xref linkend="query_address"/> about how the
+ available ports are determined.
+ For example, with the following configuration
</para>
+<programlisting>
+use-v6-udp-ports { range 32768 65535; };
+avoid-v6-udp-ports { 40000; range 50000 60000; };
+</programlisting>
+
+ <para>
+ UDP ports of IPv6 messages sent
+ from <command>named</command> will be in one
+ of the following ranges: 32768 to 39999, 40001 to 49999,
+ and 60001 to 65535.
+ </para>
+
+ <para>
+ <command>avoid-v4-udp-ports</command> and
+ <command>avoid-v6-udp-ports</command> can be used
+ to prevent <command>named</command> from choosing as its random source port a
+ port that is blocked by your firewall or a port that is
+ used by other applications;
+ if a query went out with a source port blocked by a
+ firewall, the
+ answer would not get by the firewall and the name server would
+ have to query again.
+ Note: the desired range can also be represented only with
+ <command>use-v4-udp-ports</command> and
+ <command>use-v6-udp-ports</command>, and the
+ <command>avoid-</command> options are redundant in that
+ sense; they are provided for backward compatibility and
+ to possibly simplify the port specification.
+ </para>
+ </sect3>
+
+ <sect3>
+ <title>Operating System Resource Limits</title>
+
<para>
- The TTL of a record modified by RPZ policies is set from the
- TTL of the relevant record in policy zone. It is then limited
- to a maximum value.
- The <command>max-policy-ttl</command> clause changes that
- maximum from its default of 5.
+ The server's usage of many system resources can be limited.
+ Scaled values are allowed when specifying resource limits. For
+ example, <command>1G</command> can be used instead of
+ <command>1073741824</command> to specify a limit of
+ one
+ gigabyte. <command>unlimited</command> requests
+ unlimited use, or the
+ maximum available amount. <command>default</command>
+ uses the limit
+ that was in force when the server was started. See the description
+ of <command>size_spec</command> in <xref linkend="configuration_file_elements"/>.
</para>
<para>
- For example, you might use this option statement
- </para>
-<programlisting> response-policy { zone "badlist"; };</programlisting>
- <para>
- and this zone statement
- </para>
-<programlisting> zone "badlist" {type master; file "master/badlist"; allow-query {none;}; };</programlisting>
- <para>
- with this zone file
- </para>
-<programlisting>$TTL 1H
-@ SOA LOCALHOST. named-mgr.example.com (1 1h 15m 30d 2h)
- NS LOCALHOST.
+ The following options set operating system resource limits for
+ the name server process. Some operating systems don't support
+ some or
+ any of the limits. On such systems, a warning will be issued if
+ the
+ unsupported limit is used.
+ </para>
-; QNAME policy records. There are no periods (.) after the owner names.
-nxdomain.domain.com CNAME . ; NXDOMAIN policy
-*.nxdomain.domain.com CNAME . ; NXDOMAIN policy
-nodata.domain.com CNAME *. ; NODATA policy
-*.nodata.domain.com CNAME *. ; NODATA policy
-bad.domain.com A 10.0.0.1 ; redirect to a walled garden
- AAAA 2001:2::1
-bzone.domain.com CNAME garden.example.com.
+ <variablelist>
-; do not rewrite (PASSTHRU) OK.DOMAIN.COM
-ok.domain.com CNAME rpz-passthru.
+ <varlistentry>
+ <term><command>coresize</command></term>
+ <listitem>
+ <para>
+ The maximum size of a core dump. The default
+ is <literal>default</literal>.
+ </para>
+ </listitem>
+ </varlistentry>
-; redirect x.bzone.domain.com to x.bzone.domain.com.garden.example.com
-*.bzone.domain.com CNAME *.garden.example.com.
+ <varlistentry>
+ <term><command>datasize</command></term>
+ <listitem>
+ <para>
+ The maximum amount of data memory the server
+ may use. The default is <literal>default</literal>.
+ This is a hard limit on server memory usage.
+ If the server attempts to allocate memory in excess of this
+ limit, the allocation will fail, which may in turn leave
+ the server unable to perform DNS service. Therefore,
+ this option is rarely useful as a way of limiting the
+ amount of memory used by the server, but it can be used
+ to raise an operating system data size limit that is
+ too small by default. If you wish to limit the amount
+ of memory used by the server, use the
+ <command>max-cache-size</command> and
+ <command>recursive-clients</command>
+ options instead.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>files</command></term>
+ <listitem>
+ <para>
+ The maximum number of files the server
+ may have open concurrently. The default is <literal>unlimited</literal>.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><command>stacksize</command></term>
+ <listitem>
+ <para>
+ The maximum amount of stack memory the server
+ may use. The default is <literal>default</literal>.
+ </para>
+ </listitem>
+ </varlistentry>
-; IP policy records that rewrite all responses containing A records in 127/8
-; except 127.0.0.1
-8.0.0.0.127.rpz-ip CNAME .
-32.1.0.0.127.rpz-ip CNAME rpz-passthru.
+ </variablelist>
-; NSDNAME and NSIP policy records
-ns.domain.com.rpz-nsdname CNAME .
-48.zz.2.2001.rpz-nsip CNAME .
+ </sect3>
-; blacklist and whitelist some DNS clients
-112.zz.2001.rpz-client-ip CNAME rpz-drop.
-8.0.0.0.127.rpz-client-ip CNAME rpz-drop.
+ <sect3 id="server_resource_limits">
+ <title>Server Resource Limits</title>
-; force some DNS clients and responses in the example.com zone to TCP
-16.0.0.1.10.rpz-client-ip CNAME rpz-tcp-only.
-example.com CNAME rpz-tcp-only.
-*.example.com CNAME rpz-tcp-only.
+ <para>
+ The following options set limits on the server's
+ resource consumption that are enforced internally by the
+ server rather than the operating system.
+ </para>
-</programlisting>
- <para>
- RPZ can affect server performance.
- Each configured response policy zone requires the server to
- perform one to four additional database lookups before a
- query can be answered.
- For example, a DNS server with four policy zones, each with all
- four kinds of response triggers, QNAME, IP, NSIP, and
- NSDNAME, requires a total of 17 times as many database
- lookups as a similar DNS server with no response policy zones.
- A <acronym>BIND9</acronym> server with adequate memory and one
- response policy zone with QNAME and IP triggers might achieve a
- maximum queries-per-second rate about 20% lower.
- A server with four response policy zones with QNAME and IP
- triggers might have a maximum QPS rate about 50% lower.
- </para>
-
- <para>
- Responses rewritten by RPZ are counted in the
- <command>RPZRewrites</command> statistics.
- </para>
- </sect3>
+ <variablelist>
+
+ <varlistentry>
+ <term><command>max-ixfr-log-size</command></term>
+ <listitem>
+ <para>
+ This option is obsolete; it is accepted
+ and ignored for BIND 8 compatibility. The option
+ <command>max-journal-size</command> performs a
+ similar function in BIND 9.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>max-journal-size</command></term>
+ <listitem>
+ <para>
+ Sets a maximum size for each journal file
+ (see <xref linkend="journal"/>). When the journal file
+ approaches
+ the specified size, some of the oldest transactions in the
+ journal
+ will be automatically removed. The largest permitted
+ value is 2 gigabytes. The default is
+ <literal>unlimited</literal>, which also
+ means 2 gigabytes.
+ This may also be set on a per-zone basis.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>host-statistics-max</command></term>
+ <listitem>
+ <para>
+ In BIND 8, specifies the maximum number of host statistics
+ entries to be kept.
+ Not implemented in BIND 9.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>recursive-clients</command></term>
+ <listitem>
+ <para>
+ The maximum number of simultaneous recursive lookups
+ the server will perform on behalf of clients. The default
+ is
+ <literal>1000</literal>. Because each recursing
+ client uses a fair
+ bit of memory, on the order of 20 kilobytes, the value of
+ the
+ <command>recursive-clients</command> option may
+ have to be decreased
+ on hosts with limited memory.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>tcp-clients</command></term>
+ <listitem>
+ <para>
+ The maximum number of simultaneous client TCP
+ connections that the server will accept.
+ The default is <literal>100</literal>.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>reserved-sockets</command></term>
+ <listitem>
+ <para>
+ The number of file descriptors reserved for TCP, stdio,
+ etc. This needs to be big enough to cover the number of
+ interfaces <command>named</command> listens on, <command>tcp-clients</command> as well as
+ to provide room for outgoing TCP queries and incoming zone
+ transfers. The default is <literal>512</literal>.
+ The minimum value is <literal>128</literal> and the
+ maximum value is <literal>128</literal> less than
+ maxsockets (-S). This option may be removed in the future.
+ </para>
+ <para>
+ This option has little effect on Windows.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>max-cache-size</command></term>
+ <listitem>
+ <para>
+ The maximum amount of memory to use for the
+ server's cache, in bytes.
+ When the amount of data in the cache
+ reaches this limit, the server will cause records to
+ expire prematurely based on an LRU based strategy so
+ that the limit is not exceeded.
+ The keyword <userinput>unlimited</userinput>,
+ or the value 0, will place no limit on cache size;
+ records will be purged from the cache only when their
+ TTLs expire.
+ Any positive values less than 2MB will be ignored
+ and reset to 2MB.
+ In a server with multiple views, the limit applies
+ separately to the cache of each view.
+ The default is <userinput>unlimited</userinput>.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>tcp-listen-queue</command></term>
+ <listitem>
+ <para>
+ The listen queue depth. The default and minimum is 10.
+ If the kernel supports the accept filter "dataready" this
+ also controls how
+ many TCP connections that will be queued in kernel space
+ waiting for
+ some data before being passed to accept. Nonzero values
+ less than 10 will be silently raised. A value of 0 may also
+ be used; on most platforms this sets the listen queue
+ length to a system-defined default value.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ </variablelist>
+
+ </sect3>
<sect3>
- <title>Response Rate Limiting</title>
+ <title>Periodic Task Intervals</title>
+
+ <variablelist>
+
+ <varlistentry>
+ <term><command>cleaning-interval</command></term>
+ <listitem>
+ <para>
+ This interval is effectively obsolete. Previously,
+ the server would remove expired resource records
+ from the cache every <command>cleaning-interval</command> minutes.
+ <acronym>BIND</acronym> 9 now manages cache
+ memory in a more sophisticated manner and does not
+ rely on the periodic cleaning any more.
+ Specifying this option therefore has no effect on
+ the server's behavior.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>heartbeat-interval</command></term>
+ <listitem>
+ <para>
+ The server will perform zone maintenance tasks
+ for all zones marked as <command>dialup</command> whenever this
+ interval expires. The default is 60 minutes. Reasonable
+ values are up
+ to 1 day (1440 minutes). The maximum value is 28 days
+ (40320 minutes).
+ If set to 0, no zone maintenance for these zones will occur.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>interface-interval</command></term>
+ <listitem>
+ <para>
+ The server will scan the network interface list
+ every <command>interface-interval</command>
+ minutes. The default
+ is 60 minutes. The maximum value is 28 days (40320 minutes).
+ If set to 0, interface scanning will only occur when
+ the configuration file is loaded. After the scan, the
+ server will
+ begin listening for queries on any newly discovered
+ interfaces (provided they are allowed by the
+ <command>listen-on</command> configuration), and
+ will
+ stop listening on interfaces that have gone away.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>statistics-interval</command></term>
+ <listitem>
+ <para>
+ Name server statistics will be logged
+ every <command>statistics-interval</command>
+ minutes. The default is
+ 60. The maximum value is 28 days (40320 minutes).
+ If set to 0, no statistics will be logged.
+ </para><note>
+ <simpara>
+ Not yet implemented in
+ <acronym>BIND</acronym> 9.
+ </simpara>
+ </note>
+ </listitem>
+ </varlistentry>
+
+ </variablelist>
+
+ </sect3>
+
+ <sect3 id="topology">
+ <title>Topology</title>
+
<para>
- Excessive almost identical UDP <emphasis>responses</emphasis>
- can be controlled by configuring a
- <command>rate-limit</command> clause in an
- <command>options</command> or <command>view</command> statement.
- This mechanism keeps authoritative BIND 9 from being used
- in amplifying reflection denial of service (DoS) attacks.
- Short truncated (TC=1) responses can be sent to provide
- rate-limited responses to legitimate clients within
- a range of forged, attacked IP addresses.
- Legitimate clients react to dropped or truncated response
- by retrying with UDP or with TCP respectively.
+ All other things being equal, when the server chooses a name
+ server
+ to query from a list of name servers, it prefers the one that is
+ topologically closest to itself. The <command>topology</command> statement
+ takes an <command>address_match_list</command> and
+ interprets it
+ in a special way. Each top-level list element is assigned a
+ distance.
+ Non-negated elements get a distance based on their position in the
+ list, where the closer the match is to the start of the list, the
+ shorter the distance is between it and the server. A negated match
+ will be assigned the maximum distance from the server. If there
+ is no match, the address will get a distance which is further than
+ any non-negated list element, and closer than any negated element.
+ For example,
</para>
+<programlisting>topology {
+ 10/8;
+ !1.2.3/24;
+ { 1.2/16; 3/8; };
+};</programlisting>
+
<para>
- This mechanism is intended for authoritative DNS servers.
- It can be used on recursive servers but can slow
- applications such as SMTP servers (mail receivers) and
- HTTP clients (web browsers) that repeatedly request the
- same domains.
- When possible, closing "open" recursive servers is better.
+ will prefer servers on network 10 the most, followed by hosts
+ on network 1.2.0.0 (netmask 255.255.0.0) and network 3, with the
+ exception of hosts on network 1.2.3 (netmask 255.255.255.0), which
+ is preferred least of all.
+ </para>
+ <para>
+ The default topology is
</para>
+<programlisting> topology { localhost; localnets; };
+</programlisting>
+
+ <note>
+ <simpara>
+ The <command>topology</command> option
+ is not implemented in <acronym>BIND</acronym> 9.
+ </simpara>
+ </note>
+ </sect3>
+
+ <sect3 id="the_sortlist_statement">
+
+ <title>The <command>sortlist</command> Statement</title>
+
<para>
- Response rate limiting uses a "credit" or "token bucket" scheme.
- Each combination of identical response and client
- has a conceptual account that earns a specified number
- of credits every second.
- A prospective response debits its account by one.
- Responses are dropped or truncated
- while the account is negative.
- Responses are tracked within a rolling window of time
- which defaults to 15 seconds, but can be configured with
- the <command>window</command> option to any value from
- 1 to 3600 seconds (1 hour).
- The account cannot become more positive than
- the per-second limit
- or more negative than <command>window</command>
- times the per-second limit.
- When the specified number of credits for a class of
- responses is set to 0, those responses are not rate limited.
+ The response to a DNS query may consist of multiple resource
+ records (RRs) forming a resource records set (RRset).
+ The name server will normally return the
+ RRs within the RRset in an indeterminate order
+ (but see the <command>rrset-order</command>
+ statement in <xref linkend="rrset_ordering"/>).
+ The client resolver code should rearrange the RRs as appropriate,
+ that is, using any addresses on the local net in preference to
+ other addresses.
+ However, not all resolvers can do this or are correctly
+ configured.
+ When a client is using a local server, the sorting can be performed
+ in the server, based on the client's address. This only requires
+ configuring the name servers, not all the clients.
</para>
<para>
- The notions of "identical response" and "DNS client"
- for rate limiting are not simplistic.
- All responses to an address block are counted as if to a
- single client.
- The prefix lengths of addresses blocks are
- specified with <command>ipv4-prefix-length</command> (default 24)
- and <command>ipv6-prefix-length</command> (default 56).
+ The <command>sortlist</command> statement (see below)
+ takes
+ an <command>address_match_list</command> and
+ interprets it even
+ more specifically than the <command>topology</command>
+ statement
+ does (<xref linkend="topology"/>).
+ Each top level statement in the <command>sortlist</command> must
+ itself be an explicit <command>address_match_list</command> with
+ one or two elements. The first element (which may be an IP
+ address,
+ an IP prefix, an ACL name or a nested <command>address_match_list</command>)
+ of each top level list is checked against the source address of
+ the query until a match is found.
</para>
-
<para>
- All non-empty responses for a valid domain name (qname)
- and record type (qtype) are identical and have a limit specified
- with <command>responses-per-second</command>
- (default 0 or no limit).
- All empty (NODATA) responses for a valid domain,
- regardless of query type, are identical.
- Responses in the NODATA class are limited by
- <command>nodata-per-second</command>
- (default <command>responses-per-second</command>).
- Requests for any and all undefined subdomains of a given
- valid domain result in NXDOMAIN errors, and are identical
- regardless of query type.
- They are limited by <command>nxdomain-per-second</command>
- (default <command>responses-per-second</command>).
- This controls some attacks using random names, but
- can be relaxed or turned off (set to 0)
- on servers that expect many legitimate
- NXDOMAIN responses, such as from anti-spam blacklists.
- Referrals or delegations to the server of a given
- domain are identical and are limited by
- <command>referrals-per-second</command>
- (default <command>responses-per-second</command>).
+ Once the source address of the query has been matched, if
+ the top level statement contains only one element, the actual
+ primitive
+ element that matched the source address is used to select the
+ address
+ in the response to move to the beginning of the response. If the
+ statement is a list of two elements, then the second element is
+ treated the same as the <command>address_match_list</command> in
+ a <command>topology</command> statement. Each top
+ level element
+ is assigned a distance and the address in the response with the
+ minimum
+ distance is moved to the beginning of the response.
</para>
-
<para>
- Responses generated from local wildcards are counted and limited
- as if they were for the parent domain name.
- This controls flooding using random.wild.example.com.
+ In the following example, any queries received from any of
+ the addresses of the host itself will get responses preferring
+ addresses
+ on any of the locally connected networks. Next most preferred are
+ addresses
+ on the 192.168.1/24 network, and after that either the
+ 192.168.2/24
+ or
+ 192.168.3/24 network with no preference shown between these two
+ networks. Queries received from a host on the 192.168.1/24 network
+ will prefer other addresses on that network to the 192.168.2/24
+ and
+ 192.168.3/24 networks. Queries received from a host on the
+ 192.168.4/24
+ or the 192.168.5/24 network will only prefer other addresses on
+ their directly connected networks.
</para>
+<programlisting>sortlist {
+ // IF the local host
+ // THEN first fit on the following nets
+ { localhost;
+ { localnets;
+ 192.168.1/24;
+ { 192.168.2/24; 192.168.3/24; }; }; };
+ // IF on class C 192.168.1 THEN use .1, or .2 or .3
+ { 192.168.1/24;
+ { 192.168.1/24;
+ { 192.168.2/24; 192.168.3/24; }; }; };
+ // IF on class C 192.168.2 THEN use .2, or .1 or .3
+ { 192.168.2/24;
+ { 192.168.2/24;
+ { 192.168.1/24; 192.168.3/24; }; }; };
+ // IF on class C 192.168.3 THEN use .3, or .1 or .2
+ { 192.168.3/24;
+ { 192.168.3/24;
+ { 192.168.1/24; 192.168.2/24; }; }; };
+ // IF .4 or .5 THEN prefer that net
+ { { 192.168.4/24; 192.168.5/24; };
+ };
+};</programlisting>
+
<para>
- All requests that result in DNS errors other
- than NXDOMAIN, such as SERVFAIL and FORMERR, are identical
- regardless of requested name (qname) or record type (qtype).
- This controls attacks using invalid requests or distant,
- broken authoritative servers.
- By default the limit on errors is the same as the
- <command>responses-per-second</command> value,
- but it can be set separately with
- <command>errors-per-second</command>.
+ The following example will give reasonable behavior for the
+ local host and hosts on directly connected networks. It is similar
+ to the behavior of the address sort in <acronym>BIND</acronym> 4.9.x. Responses sent
+ to queries from the local host will favor any of the directly
+ connected
+ networks. Responses sent to queries from any other hosts on a
+ directly
+ connected network will prefer addresses on that same network.
+ Responses
+ to other queries will not be sorted.
</para>
+<programlisting>sortlist {
+ { localhost; localnets; };
+ { localnets; };
+};
+</programlisting>
+
+ </sect3>
+ <sect3 id="rrset_ordering">
+ <title id="rrset_ordering_title">RRset Ordering</title>
<para>
- Many attacks using DNS involve UDP requests with forged source
- addresses.
- Rate limiting prevents the use of BIND 9 to flood a network
- with responses to requests with forged source addresses,
- but could let a third party block responses to legitimate requests.
- There is a mechanism that can answer some legitimate
- requests from a client whose address is being forged in a flood.
- Setting <command>slip</command> to 2 (its default) causes every
- other UDP request to be answered with a small truncated (TC=1)
+ When multiple records are returned in an answer it may be
+ useful to configure the order of the records placed into the
response.
- The small size and reduced frequency, and so lack of
- amplification, of "slipped" responses make them unattractive
- for reflection DoS attacks.
- <command>slip</command> must be between 0 and 10.
- A value of 0 does not "slip":
- no truncated responses are sent due to rate limiting,
- all responses are dropped.
- A value of 1 causes every response to slip;
- values between 2 and 10 cause every n'th response to slip.
- Some error responses including REFUSED and SERVFAIL
- cannot be replaced with truncated responses and are instead
- leaked at the <command>slip</command> rate.
+ The <command>rrset-order</command> statement permits
+ configuration
+ of the ordering of the records in a multiple record response.
+ See also the <command>sortlist</command> statement,
+ <xref linkend="the_sortlist_statement"/>.
</para>
<para>
- (NOTE: Dropped responses from an authoritative server may
- reduce the difficulty of a third party successfully forging
- a response to a recursive resolver. The best security
- against forged responses is for authoritative operators
- to sign their zones using DNSSEC and for resolver operators
- to validate the responses. When this is not an option,
- operators who are more concerned with response integrity
- than with flood mitigation may consider setting
- <command>slip</command> to 1, causing all rate-limited
- responses to be truncated rather than dropped. This reduces
- the effectiveness of rate-limiting against reflection attacks.)
+ An <command>order_spec</command> is defined as
+ follows:
</para>
-
<para>
- When the approximate query per second rate exceeds
- the <command>qps-scale</command> value,
- then the <command>responses-per-second</command>,
- <command>errors-per-second</command>,
- <command>nxdomains-per-second</command> and
- <command>all-per-second</command> values are reduced by the
- ratio of the current rate to the <command>qps-scale</command> value.
- This feature can tighten defenses during attacks.
- For example, with
- <command>qps-scale 250; responses-per-second 20;</command> and
- a total query rate of 1000 queries/second for all queries from
- all DNS clients including via TCP,
- then the effective responses/second limit changes to
- (250/1000)*20 or 5.
- Responses sent via TCP are not limited
- but are counted to compute the query per second rate.
+ <optional>class <replaceable>class_name</replaceable></optional>
+ <optional>type <replaceable>type_name</replaceable></optional>
+ <optional>name <replaceable>"domain_name"</replaceable></optional>
+ order <replaceable>ordering</replaceable>
</para>
-
<para>
- Communities of DNS clients can be given their own parameters or no
- rate limiting by putting
- <command>rate-limit</command> statements in <command>view</command>
- statements instead of the global <command>option</command>
- statement.
- A <command>rate-limit</command> statement in a view replaces,
- rather than supplementing, a <command>rate-limit</command>
- statement among the main options.
- DNS clients within a view can be exempted from rate limits
- with the <command>exempt-clients</command> clause.
+ If no class is specified, the default is <command>ANY</command>.
+ If no type is specified, the default is <command>ANY</command>.
+ If no name is specified, the default is "<command>*</command>" (asterisk).
</para>
-
<para>
- UDP responses of all kinds can be limited with the
- <command>all-per-second</command> phrase.
- This rate limiting is unlike the rate limiting provided by
- <command>responses-per-second</command>,
- <command>errors-per-second</command>, and
- <command>nxdomains-per-second</command> on a DNS server
- which are often invisible to the victim of a DNS reflection attack.
- Unless the forged requests of the attack are the same as the
- legitimate requests of the victim, the victim's requests are
- not affected.
- Responses affected by an <command>all-per-second</command> limit
- are always dropped; the <command>slip</command> value has no
- effect.
- An <command>all-per-second</command> limit should be
- at least 4 times as large as the other limits,
- because single DNS clients often send bursts of legitimate
- requests.
- For example, the receipt of a single mail message can prompt
- requests from an SMTP server for NS, PTR, A, and AAAA records
- as the incoming SMTP/TCP/IP connection is considered.
- The SMTP server can need additional NS, A, AAAA, MX, TXT, and SPF
- records as it considers the STMP <command>Mail From</command>
- command.
- Web browsers often repeatedly resolve the same names that
- are repeated in HTML <IMG> tags in a page.
- <command>All-per-second</command> is similar to the
- rate limiting offered by firewalls but often inferior.
- Attacks that justify ignoring the
- contents of DNS responses are likely to be attacks on the
- DNS server itself.
- They usually should be discarded before the DNS server
- spends resources making TCP connections or parsing DNS requests,
- but that rate limiting must be done before the
- DNS server sees the requests.
+ The legal values for <command>ordering</command> are:
</para>
-
+ <informaltable colsep="0" rowsep="0">
+ <tgroup cols="2" colsep="0" rowsep="0" tgroupstyle="4Level-table">
+ <colspec colname="1" colnum="1" colsep="0" colwidth="0.750in"/>
+ <colspec colname="2" colnum="2" colsep="0" colwidth="3.750in"/>
+ <tbody>
+ <row rowsep="0">
+ <entry colname="1">
+ <para><command>fixed</command></para>
+ </entry>
+ <entry colname="2">
+ <para>
+ Records are returned in the order they
+ are defined in the zone file.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para><command>random</command></para>
+ </entry>
+ <entry colname="2">
+ <para>
+ Records are returned in some random order.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para><command>cyclic</command></para>
+ </entry>
+ <entry colname="2">
+ <para>
+ Records are returned in a cyclic round-robin order.
+ </para>
+ <para>
+ If <acronym>BIND</acronym> is configured with the
+ "--enable-fixed-rrset" option at compile time, then
+ the initial ordering of the RRset will match the
+ one specified in the zone file.
+ </para>
+ </entry>
+ </row>
+ </tbody>
+ </tgroup>
+ </informaltable>
<para>
- The maximum size of the table used to track requests and
- rate limit responses is set with <command>max-table-size</command>.
- Each entry in the table is between 40 and 80 bytes.
- The table needs approximately as many entries as the number
- of requests received per second.
- The default is 20,000.
- To reduce the cold start of growing the table,
- <command>min-table-size</command> (default 500)
- can set the minimum table size.
- Enable <command>rate-limit</command> category logging to monitor
- expansions of the table and inform
- choices for the initial and maximum table size.
+ For example:
</para>
+<programlisting>rrset-order {
+ class IN type A name "host.example.com" order random;
+ order cyclic;
+};
+</programlisting>
+
<para>
- Use <command>log-only yes</command> to test rate limiting parameters
- without actually dropping any requests.
+ will cause any responses for type A records in class IN that
+ have "<literal>host.example.com</literal>" as a
+ suffix, to always be returned
+ in random order. All other records are returned in cyclic order.
</para>
-
<para>
- Responses dropped by rate limits are included in the
- <command>RateDropped</command> and <command>QryDropped</command>
- statistics.
- Responses that truncated by rate limits are included in
- <command>RateSlipped</command> and <command>RespTruncated</command>.
- </para>
+ If multiple <command>rrset-order</command> statements
+ appear, they are not combined — the last one applies.
+ </para>
+ <para>
+ By default, all records are returned in random order.
+ </para>
+
+ <note>
+ <simpara>
+ In this release of <acronym>BIND</acronym> 9, the
+ <command>rrset-order</command> statement does not support
+ "fixed" ordering by default. Fixed ordering can be enabled
+ at compile time by specifying "--enable-fixed-rrset" on
+ the "configure" command line.
+ </simpara>
+ </note>
</sect3>
- </sect2>
- <sect2 id="server_statement_grammar">
- <title><command>server</command> Statement Grammar</title>
+ <sect3 id="tuning">
+ <title>Tuning</title>
-<programlisting><command>server</command> <replaceable>ip_addr[/prefixlen]</replaceable> {
- <optional> bogus <replaceable>yes_or_no</replaceable> ; </optional>
- <optional> provide-ixfr <replaceable>yes_or_no</replaceable> ; </optional>
- <optional> request-ixfr <replaceable>yes_or_no</replaceable> ; </optional>
- <optional> edns <replaceable>yes_or_no</replaceable> ; </optional>
- <optional> edns-udp-size <replaceable>number</replaceable> ; </optional>
- <optional> max-udp-size <replaceable>number</replaceable> ; </optional>
- <optional> transfers <replaceable>number</replaceable> ; </optional>
- <optional> transfer-format <replaceable>( one-answer | many-answers )</replaceable> ; ]</optional>
- <optional> keys <replaceable>{ string ; <optional> string ; <optional>...</optional></optional> }</replaceable> ; </optional>
- <optional> transfer-source (<replaceable>ip4_addr</replaceable> | <constant>*</constant>) <optional>port <replaceable>ip_port</replaceable></optional> <optional>dscp <replaceable>ip_dscp</replaceable></optional> ; </optional>
- <optional> transfer-source-v6 (<replaceable>ip6_addr</replaceable> | <constant>*</constant>) <optional>port <replaceable>ip_port</replaceable></optional> <optional>dscp <replaceable>ip_dscp</replaceable></optional> ; </optional>
- <optional> notify-source (<replaceable>ip4_addr</replaceable> | <constant>*</constant>) <optional>port <replaceable>ip_port</replaceable></optional> <optional>dscp <replaceable>ip_dscp</replaceable></optional> ; </optional>
- <optional> notify-source-v6 (<replaceable>ip6_addr</replaceable> | <constant>*</constant>) <optional>port <replaceable>ip_port</replaceable></optional> <optional>dscp <replaceable>ip_dscp</replaceable></optional> ; </optional>
- <optional> query-source <optional> address ( <replaceable>ip_addr</replaceable> | <replaceable>*</replaceable> ) </optional>
- <optional> port ( <replaceable>ip_port</replaceable> | <replaceable>*</replaceable> ) </optional> <optional>dscp <replaceable>ip_dscp</replaceable></optional> ; </optional>
- <optional> query-source-v6 <optional> address ( <replaceable>ip_addr</replaceable> | <replaceable>*</replaceable> ) </optional>
- <optional> port ( <replaceable>ip_port</replaceable> | <replaceable>*</replaceable> ) </optional> <optional>dscp <replaceable>ip_dscp</replaceable></optional> ; </optional>
- <optional> use-queryport-pool <replaceable>yes_or_no</replaceable>; </optional>
- <optional> queryport-pool-ports <replaceable>number</replaceable>; </optional>
- <optional> queryport-pool-updateinterval <replaceable>number</replaceable>; </optional>
-};
-</programlisting>
+ <variablelist>
- </sect2>
-
- <sect2 id="server_statement_definition_and_usage">
- <title><command>server</command> Statement Definition and
- Usage</title>
-
- <para>
- The <command>server</command> statement defines
- characteristics
- to be associated with a remote name server. If a prefix length is
- specified, then a range of servers is covered. Only the most
- specific
- server clause applies regardless of the order in
- <filename>named.conf</filename>.
- </para>
-
- <para>
- The <command>server</command> statement can occur at
- the top level of the
- configuration file or inside a <command>view</command>
- statement.
- If a <command>view</command> statement contains
- one or more <command>server</command> statements, only
- those
- apply to the view and any top-level ones are ignored.
- If a view contains no <command>server</command>
- statements,
- any top-level <command>server</command> statements are
- used as
- defaults.
- </para>
-
- <para>
- If you discover that a remote server is giving out bad data,
- marking it as bogus will prevent further queries to it. The
- default
- value of <command>bogus</command> is <command>no</command>.
- </para>
- <para>
- The <command>provide-ixfr</command> clause determines
- whether
- the local server, acting as master, will respond with an
- incremental
- zone transfer when the given remote server, a slave, requests it.
- If set to <command>yes</command>, incremental transfer
- will be provided
- whenever possible. If set to <command>no</command>,
- all transfers
- to the remote server will be non-incremental. If not set, the
- value
- of the <command>provide-ixfr</command> option in the
- view or
- global options block is used as a default.
- </para>
-
- <para>
- The <command>request-ixfr</command> clause determines
- whether
- the local server, acting as a slave, will request incremental zone
- transfers from the given remote server, a master. If not set, the
- value of the <command>request-ixfr</command> option in
- the view or global options block is used as a default. It may
- also be set in the zone block and, if set there, it will
- override the global or view setting for that zone.
- </para>
-
- <para>
- IXFR requests to servers that do not support IXFR will
- automatically
- fall back to AXFR. Therefore, there is no need to manually list
- which servers support IXFR and which ones do not; the global
- default
- of <command>yes</command> should always work.
- The purpose of the <command>provide-ixfr</command> and
- <command>request-ixfr</command> clauses is
- to make it possible to disable the use of IXFR even when both
- master
- and slave claim to support it, for example if one of the servers
- is buggy and crashes or corrupts data when IXFR is used.
- </para>
-
- <para>
- The <command>edns</command> clause determines whether
- the local server will attempt to use EDNS when communicating
- with the remote server. The default is <command>yes</command>.
- </para>
+ <varlistentry>
+ <term><command>lame-ttl</command></term>
+ <listitem>
+ <para>
+ Sets the number of seconds to cache a
+ lame server indication. 0 disables caching. (This is
+ <emphasis role="bold">NOT</emphasis> recommended.)
+ The default is <literal>600</literal> (10 minutes) and the
+ maximum value is
+ <literal>1800</literal> (30 minutes).
+ </para>
- <para>
- The <command>edns-udp-size</command> option sets the EDNS UDP size
- that is advertised by <command>named</command> when querying the remote server.
- Valid values are 512 to 4096 bytes (values outside this range will be
- silently adjusted). This option is useful when you wish to
- advertises a different value to this server than the value you
- advertise globally, for example, when there is a firewall at the
- remote site that is blocking large replies.
- </para>
+ <para>
+ Lame-ttl also controls the amount of time DNSSEC
+ validation failures are cached. There is a minimum
+ of 30 seconds applied to bad cache entries if the
+ lame-ttl is set to less than 30 seconds.
+ </para>
- <para>
- The <command>max-udp-size</command> option sets the
- maximum EDNS UDP message size <command>named</command> will send. Valid
- values are 512 to 4096 bytes (values outside this range will
- be silently adjusted). This option is useful when you
- know that there is a firewall that is blocking large
- replies from <command>named</command>.
- </para>
-
- <para>
- The server supports two zone transfer methods. The first, <command>one-answer</command>,
- uses one DNS message per resource record transferred. <command>many-answers</command> packs
- as many resource records as possible into a message. <command>many-answers</command> is
- more efficient, but is only known to be understood by <acronym>BIND</acronym> 9, <acronym>BIND</acronym>
- 8.x, and patched versions of <acronym>BIND</acronym>
- 4.9.5. You can specify which method
- to use for a server with the <command>transfer-format</command> option.
- If <command>transfer-format</command> is not
- specified, the <command>transfer-format</command>
- specified
- by the <command>options</command> statement will be
- used.
- </para>
-
- <para><command>transfers</command>
- is used to limit the number of concurrent inbound zone
- transfers from the specified server. If no
- <command>transfers</command> clause is specified, the
- limit is set according to the
- <command>transfers-per-ns</command> option.
- </para>
-
- <para>
- The <command>keys</command> clause identifies a
- <command>key_id</command> defined by the <command>key</command> statement,
- to be used for transaction security (TSIG, <xref linkend="tsig"/>)
- when talking to the remote server.
- When a request is sent to the remote server, a request signature
- will be generated using the key specified here and appended to the
- message. A request originating from the remote server is not
- required
- to be signed by this key.
- </para>
-
- <para>
- Although the grammar of the <command>keys</command>
- clause
- allows for multiple keys, only a single key per server is
- currently
- supported.
- </para>
-
- <para>
- The <command>transfer-source</command> and
- <command>transfer-source-v6</command> clauses specify
- the IPv4 and IPv6 source
- address to be used for zone transfer with the remote server,
- respectively.
- For an IPv4 remote server, only <command>transfer-source</command> can
- be specified.
- Similarly, for an IPv6 remote server, only
- <command>transfer-source-v6</command> can be
- specified.
- For more details, see the description of
- <command>transfer-source</command> and
- <command>transfer-source-v6</command> in
- <xref linkend="zone_transfers"/>.
- </para>
-
- <para>
- The <command>notify-source</command> and
- <command>notify-source-v6</command> clauses specify the
- IPv4 and IPv6 source address to be used for notify
- messages sent to remote servers, respectively. For an
- IPv4 remote server, only <command>notify-source</command>
- can be specified. Similarly, for an IPv6 remote server,
- only <command>notify-source-v6</command> can be specified.
- </para>
-
- <para>
- The <command>query-source</command> and
- <command>query-source-v6</command> clauses specify the
- IPv4 and IPv6 source address to be used for queries
- sent to remote servers, respectively. For an IPv4
- remote server, only <command>query-source</command> can
- be specified. Similarly, for an IPv6 remote server,
- only <command>query-source-v6</command> can be specified.
- </para>
+ </listitem>
+ </varlistentry>
- </sect2>
+ <varlistentry>
+ <term><command>max-ncache-ttl</command></term>
+ <listitem>
+ <para>
+ To reduce network traffic and increase performance,
+ the server stores negative answers. <command>max-ncache-ttl</command> is
+ used to set a maximum retention time for these answers in
+ the server
+ in seconds. The default
+ <command>max-ncache-ttl</command> is <literal>10800</literal> seconds (3 hours).
+ <command>max-ncache-ttl</command> cannot exceed
+ 7 days and will
+ be silently truncated to 7 days if set to a greater value.
+ </para>
+ </listitem>
+ </varlistentry>
- <sect2 id="statschannels">
- <title><command>statistics-channels</command> Statement Grammar</title>
+ <varlistentry>
+ <term><command>max-cache-ttl</command></term>
+ <listitem>
+ <para>
+ Sets the maximum time for which the server will
+ cache ordinary (positive) answers. The default is
+ one week (7 days).
+ A value of zero may cause all queries to return
+ SERVFAIL, because of lost caches of intermediate
+ RRsets (such as NS and glue AAAA/A records) in the
+ resolution process.
+ </para>
+ </listitem>
+ </varlistentry>
-<programlisting><command>statistics-channels</command> {
- [ inet ( ip_addr | * ) [ port ip_port ]
- [ allow { <replaceable> address_match_list </replaceable> } ]; ]
- [ inet ...; ]
-};
-</programlisting>
- </sect2>
+ <varlistentry>
+ <term><command>min-roots</command></term>
+ <listitem>
+ <para>
+ The minimum number of root servers that
+ is required for a request for the root servers to be
+ accepted. The default
+ is <userinput>2</userinput>.
+ </para>
+ <note>
+ <simpara>
+ Not implemented in <acronym>BIND</acronym> 9.
+ </simpara>
+ </note>
+ </listitem>
+ </varlistentry>
- <sect2>
- <title><command>statistics-channels</command> Statement Definition and
- Usage</title>
+ <varlistentry>
+ <term><command>sig-validity-interval</command></term>
+ <listitem>
+ <para>
+ Specifies the number of days into the future when
+ DNSSEC signatures automatically generated as a
+ result of dynamic updates (<xref
+ linkend="dynamic_update"/>) will expire. There
+ is an optional second field which specifies how
+ long before expiry that the signatures will be
+ regenerated. If not specified, the signatures will
+ be regenerated at 1/4 of base interval. The second
+ field is specified in days if the base interval is
+ greater than 7 days otherwise it is specified in hours.
+ The default base interval is <literal>30</literal> days
+ giving a re-signing interval of 7 1/2 days. The maximum
+ values are 10 years (3660 days).
+ </para>
+ <para>
+ The signature inception time is unconditionally
+ set to one hour before the current time to allow
+ for a limited amount of clock skew.
+ </para>
+ <para>
+ The <command>sig-validity-interval</command>
+ should be, at least, several multiples of the SOA
+ expire interval to allow for reasonable interaction
+ between the various timer and expiry dates.
+ </para>
+ </listitem>
+ </varlistentry>
- <para>
- The <command>statistics-channels</command> statement
- declares communication channels to be used by system
- administrators to get access to statistics information of
- the name server.
- </para>
+ <varlistentry>
+ <term><command>sig-signing-nodes</command></term>
+ <listitem>
+ <para>
+ Specify the maximum number of nodes to be
+ examined in each quantum when signing a zone with
+ a new DNSKEY. The default is
+ <literal>100</literal>.
+ </para>
+ </listitem>
+ </varlistentry>
- <para>
- This statement intends to be flexible to support multiple
- communication protocols in the future, but currently only
- HTTP access is supported.
- It requires that BIND 9 be compiled with libxml2 and/or
- json-c (also known as libjson0); the
- <command>statistics-channels</command> statement is
- still accepted even if it is built without the library,
- but any HTTP access will fail with an error.
- </para>
+ <varlistentry>
+ <term><command>sig-signing-signatures</command></term>
+ <listitem>
+ <para>
+ Specify a threshold number of signatures that
+ will terminate processing a quantum when signing
+ a zone with a new DNSKEY. The default is
+ <literal>10</literal>.
+ </para>
+ </listitem>
+ </varlistentry>
- <para>
- An <command>inet</command> control channel is a TCP socket
- listening at the specified <command>ip_port</command> on the
- specified <command>ip_addr</command>, which can be an IPv4 or IPv6
- address. An <command>ip_addr</command> of <literal>*</literal>
- (asterisk) is
- interpreted as the IPv4 wildcard address; connections will be
- accepted on any of the system's IPv4 addresses.
- To listen on the IPv6 wildcard address,
- use an <command>ip_addr</command> of <literal>::</literal>.
- </para>
+ <varlistentry>
+ <term><command>sig-signing-type</command></term>
+ <listitem>
+ <para>
+ Specify a private RDATA type to be used when generating
+ key signing records. The default is
+ <literal>65534</literal>.
+ </para>
+ <para>
+ It is expected that this parameter may be removed
+ in a future version once there is a standard type.
+ </para>
+ <para>
+ These records can be removed from the zone once named
+ has completed signing the zone with the matching key
+ using <command>nsupdate</command> or
+ <command>rndc signing -clear</command>.
+ <command>rndc signing -clear</command> is the only supported
+ way to remove these records from
+ <command>inline-signing</command> zones.
+ </para>
+ </listitem>
+ </varlistentry>
- <para>
- If no port is specified, port 80 is used for HTTP channels.
- The asterisk "<literal>*</literal>" cannot be used for
- <command>ip_port</command>.
- </para>
+ <varlistentry>
+ <term><command>min-refresh-time</command></term>
+ <term><command>max-refresh-time</command></term>
+ <term><command>min-retry-time</command></term>
+ <term><command>max-retry-time</command></term>
+ <listitem>
+ <para>
+ These options control the server's behavior on refreshing a
+ zone
+ (querying for SOA changes) or retrying failed transfers.
+ Usually the SOA values for the zone are used, but these
+ values
+ are set by the master, giving slave server administrators
+ little
+ control over their contents.
+ </para>
+ <para>
+ These options allow the administrator to set a minimum and
+ maximum
+ refresh and retry time either per-zone, per-view, or
+ globally.
+ These options are valid for slave and stub zones,
+ and clamp the SOA refresh and retry times to the specified
+ values.
+ </para>
+ <para>
+ The following defaults apply.
+ <command>min-refresh-time</command> 300 seconds,
+ <command>max-refresh-time</command> 2419200 seconds
+ (4 weeks), <command>min-retry-time</command> 500 seconds,
+ and <command>max-retry-time</command> 1209600 seconds
+ (2 weeks).
+ </para>
+ </listitem>
+ </varlistentry>
- <para>
- The attempt of opening a statistics channel is
- restricted by the optional <command>allow</command> clause.
- Connections to the statistics channel are permitted based on the
- <command>address_match_list</command>.
- If no <command>allow</command> clause is present,
- <command>named</command> accepts connection
- attempts from any address; since the statistics may
- contain sensitive internal information, it is highly
- recommended to restrict the source of connection requests
- appropriately.
- </para>
-
- <para>
- If no <command>statistics-channels</command> statement is present,
- <command>named</command> will not open any communication channels.
- </para>
-
- <para>
- The statistics are available in various formats and views
- depending on the URI used to access them. For example, if
- the statistics channel is configured to listen on 127.0.0.1
- port 8888, then the statistics are accessible in XML format at
- <ulink url="http://127.0.0.1:8888/"
- >http://127.0.0.1:8888/</ulink> or
- <ulink url="http://127.0.0.1:8888/xml"
- >http://127.0.0.1:8888/xml</ulink>. A CSS file is
- included which can format the XML statistics into tables
- when viewed with a stylesheet-capable browser, and into
- charts and graphs using the Google Charts API when using a
- javascript-capable browser.
- </para>
-
- <para>
- Applications that depend on a particular XML schema
- can request
- <ulink url="http://127.0.0.1:8888/xml/v2"
- >http://127.0.0.1:8888/xml/v2</ulink> for version 2
- of the statistics XML schema or
- <ulink url="http://127.0.0.1:8888/xml/v3"
- >http://127.0.0.1:8888/xml/v3</ulink> for version 3.
- If the requested schema is supported by the server, then
- it will respond; if not, it will return a "page not found"
- error.
- </para>
-
- <para>
- Broken-out subsets of the statistics can be viewed at
- <ulink url="http://127.0.0.1:8888/xml/v3/status"
- >http://127.0.0.1:8888/xml/v3/status</ulink>
- (server uptime and last reconfiguration time),
- <ulink url="http://127.0.0.1:8888/xml/v3/server"
- >http://127.0.0.1:8888/xml/v3/server</ulink>
- (server and resolver statistics),
- <ulink url="http://127.0.0.1:8888/xml/v3/zones"
- >http://127.0.0.1:8888/xml/v3/zones</ulink>
- (zone statistics),
- <ulink url="http://127.0.0.1:8888/xml/v3/net"
- >http://127.0.0.1:8888/xml/v3/net</ulink>
- (network status and socket statistics),
- <ulink url="http://127.0.0.1:8888/xml/v3/mem"
- >http://127.0.0.1:8888/xml/v3/mem</ulink>
- (memory manager statistics),
- <ulink url="http://127.0.0.1:8888/xml/v3/tasks"
- >http://127.0.0.1:8888/xml/v3/tasks</ulink>
- (task manager statistics).
- </para>
-
- <para>
- The full set of statistics can also be read in JSON format at
- <ulink url="http://127.0.0.1:8888/json"
- >http://127.0.0.1:8888/json</ulink>,
- with the broken-out subsets at
- <ulink url="http://127.0.0.1:8888/json/v1/status"
- >http://127.0.0.1:8888/json/v1/status</ulink>
- (server uptime and last reconfiguration time),
- <ulink url="http://127.0.0.1:8888/json/v1/server"
- >http://127.0.0.1:8888/json/v1/server</ulink>
- (server and resolver statistics),
- <ulink url="http://127.0.0.1:8888/json/v1/zones"
- >http://127.0.0.1:8888/json/v1/zones</ulink>
- (zone statistics),
- <ulink url="http://127.0.0.1:8888/json/v1/net"
- >http://127.0.0.1:8888/json/v1/net</ulink>
- (network status and socket statistics),
- <ulink url="http://127.0.0.1:8888/json/v1/mem"
- >http://127.0.0.1:8888/json/v1/mem</ulink>
- (memory manager statistics),
- <ulink url="http://127.0.0.1:8888/json/v1/tasks"
- >http://127.0.0.1:8888/json/v1/tasks</ulink>
- (task manager statistics).
- </para>
- </sect2>
+ <varlistentry>
+ <term><command>edns-udp-size</command></term>
+ <listitem>
+ <para>
+ Sets the initial advertised EDNS UDP buffer size in
+ bytes, to control the size of packets received from
+ authoritative servers in response to recursive queries.
+ Valid values are 512 to 4096 (values outside this range
+ will be silently adjusted). The default value is 4096.
+ </para>
+ <para>
+ The usual reason for setting
+ <command>edns-udp-size</command> to a non-default value
+ is to get UDP answers to pass through broken firewalls
+ that block fragmented packets and/or block UDP DNS
+ packets that are greater than 512 bytes.
+ </para>
+ <para>
+ When <command>named</command> first queries a remote
+ server, it will advertise a UDP buffer size of 512, as
+ this has the greatest chance of success on the first try.
+ </para>
+ <para>
+ If the initial response times out, <command>named</command>
+ will try again with plain DNS, and if that is successful,
+ it will be taken as evidence that the server does not
+ support EDNS. After enough failures using EDNS and
+ successes using plain DNS, <command>named</command>
+ will default to plain DNS for future communications
+ with that server. (Periodically, <command>named</command>
+ will an EDNS query to see if the situation has improved.)
+ </para>
+ <para>
+ However, if the initial query is successful with
+ EDNS advertising a buffer size of 512, then
+ <command>named</command> will advertise progressively
+ larger buffer sizes on successive queries, until
+ responses begin timing out or
+ <command>edns-udp-size</command> is reached.
+ </para>
+ <para>
+ The default buffer sizes used by <command>named</command>
+ are 512, 1232, 1432, and 4096, but never exceeding
+ <command>edns-udp-size</command>. (The values 1232 and
+ 1432 are chosen to allow for an IPv4/IPv6 encapsulated
+ UDP message to be sent without fragmentation at Ethernet
+ and IPv6 network mimimum MTU sizes.)
+ </para>
+ </listitem>
+ </varlistentry>
- <sect2 id="trusted-keys">
- <title><command>trusted-keys</command> Statement Grammar</title>
+ <varlistentry>
+ <term><command>max-udp-size</command></term>
+ <listitem>
+ <para>
+ Sets the maximum EDNS UDP message size
+ <command>named</command> will send in bytes.
+ Valid values are 512 to 4096 (values outside this
+ range will be silently adjusted). The default
+ value is 4096.
+ </para>
+ <para>
+ This value applies to responses sent by a server; to
+ set the advertised buffer size in queries, see
+ <command>edns-udp-size</command>.
+ </para>
+ <para>
+ The usual reason for setting
+ <command>max-udp-size</command> to a non-default
+ value is to get UDP answers to pass through broken
+ firewalls that block fragmented packets and/or
+ block UDP packets that are greater than 512 bytes.
+ This is independent of the advertised receive
+ buffer (<command>edns-udp-size</command>).
+ </para>
+ <para>
+ Setting this to a low value will encourage additional
+ TCP traffic to the nameserver.
+ </para>
+ </listitem>
+ </varlistentry>
-<programlisting><command>trusted-keys</command> {
- <replaceable>string</replaceable> <replaceable>number</replaceable> <replaceable>number</replaceable> <replaceable>number</replaceable> <replaceable>string</replaceable> ;
- <optional> <replaceable>string</replaceable> <replaceable>number</replaceable> <replaceable>number</replaceable> <replaceable>number</replaceable> <replaceable>string</replaceable> ; <optional>...</optional></optional>
-};
-</programlisting>
+ <varlistentry>
+ <term><command>masterfile-format</command></term>
+ <listitem>
+ <para>Specifies
+ the file format of zone files (see
+ <xref linkend="zonefile_format"/>).
+ The default value is <constant>text</constant>, which is the
+ standard textual representation, except for slave zones,
+ in which the default value is <constant>raw</constant>.
+ Files in other formats than <constant>text</constant> are
+ typically expected to be generated by the
+ <command>named-compilezone</command> tool, or dumped by
+ <command>named</command>.
+ </para>
+ <para>
+ Note that when a zone file in a different format than
+ <constant>text</constant> is loaded, <command>named</command>
+ may omit some of the checks which would be performed for a
+ file in the <constant>text</constant> format. In particular,
+ <command>check-names</command> checks do not apply
+ for the <constant>raw</constant> format. This means
+ a zone file in the <constant>raw</constant> format
+ must be generated with the same check level as that
+ specified in the <command>named</command> configuration
+ file. Also, <constant>map</constant> format files are
+ loaded directly into memory via memory mapping, with only
+ minimal checking.
+ </para>
+ <para>
+ This statement sets the
+ <command>masterfile-format</command> for all zones,
+ but can be overridden on a per-zone or per-view basis
+ by including a <command>masterfile-format</command>
+ statement within the <command>zone</command> or
+ <command>view</command> block in the configuration
+ file.
+ </para>
+ </listitem>
+ </varlistentry>
- </sect2>
- <sect2>
- <title><command>trusted-keys</command> Statement Definition
- and Usage</title>
- <para>
- The <command>trusted-keys</command> statement defines
- DNSSEC security roots. DNSSEC is described in <xref
- linkend="DNSSEC"/>. A security root is defined when the
- public key for a non-authoritative zone is known, but
- cannot be securely obtained through DNS, either because
- it is the DNS root zone or because its parent zone is
- unsigned. Once a key has been configured as a trusted
- key, it is treated as if it had been validated and
- proven secure. The resolver attempts DNSSEC validation
- on all DNS data in subdomains of a security root.
- </para>
- <para>
- All keys (and corresponding zones) listed in
- <command>trusted-keys</command> are deemed to exist regardless
- of what parent zones say. Similarly for all keys listed in
- <command>trusted-keys</command> only those keys are
- used to validate the DNSKEY RRset. The parent's DS RRset
- will not be used.
- </para>
- <para>
- The <command>trusted-keys</command> statement can contain
- multiple key entries, each consisting of the key's
- domain name, flags, protocol, algorithm, and the Base-64
- representation of the key data.
- Spaces, tabs, newlines and carriage returns are ignored
- in the key data, so the configuration may be split up into
- multiple lines.
- </para>
- <para>
- <command>trusted-keys</command> may be set at the top level
- of <filename>named.conf</filename> or within a view. If it is
- set in both places, they are additive: keys defined at the top
- level are inherited by all views, but keys defined in a view
- are only used within that view.
- </para>
- </sect2>
+ <varlistentry id="clients-per-query">
+ <term><command>clients-per-query</command></term>
+ <term><command>max-clients-per-query</command></term>
+ <listitem>
+ <para>These set the
+ initial value (minimum) and maximum number of recursive
+ simultaneous clients for any given query
+ (<qname,qtype,qclass>) that the server will accept
+ before dropping additional clients. <command>named</command> will attempt to
+ self tune this value and changes will be logged. The
+ default values are 10 and 100.
+ </para>
+ <para>
+ This value should reflect how many queries come in for
+ a given name in the time it takes to resolve that name.
+ If the number of queries exceed this value, <command>named</command> will
+ assume that it is dealing with a non-responsive zone
+ and will drop additional queries. If it gets a response
+ after dropping queries, it will raise the estimate. The
+ estimate will then be lowered in 20 minutes if it has
+ remained unchanged.
+ </para>
+ <para>
+ If <command>clients-per-query</command> is set to zero,
+ then there is no limit on the number of clients per query
+ and no queries will be dropped.
+ </para>
+ <para>
+ If <command>max-clients-per-query</command> is set to zero,
+ then there is no upper bound other than imposed by
+ <command>recursive-clients</command>.
+ </para>
+ </listitem>
+ </varlistentry>
- <sect2>
- <title><command>managed-keys</command> Statement Grammar</title>
+ <varlistentry>
+ <term><command>notify-delay</command></term>
+ <listitem>
+ <para>
+ The delay, in seconds, between sending sets of notify
+ messages for a zone. The default is five (5) seconds.
+ </para>
+ <para>
+ The overall rate that NOTIFY messages are sent for all
+ zones is controlled by <command>serial-query-rate</command>.
+ </para>
+ </listitem>
+ </varlistentry>
-<programlisting><command>managed-keys</command> {
- <replaceable>name</replaceable> <literal>initial-key</literal> <replaceable>flags</replaceable> <replaceable>protocol</replaceable> <replaceable>algorithm</replaceable> <replaceable>key-data</replaceable> ;
- <optional> <replaceable>name</replaceable> <literal>initial-key</literal> <replaceable>flags</replaceable> <replaceable>protocol</replaceable> <replaceable>algorithm</replaceable> <replaceable>key-data</replaceable> ; <optional>...</optional></optional>
-};
-</programlisting>
+ <varlistentry>
+ <term><command>max-rsa-exponent-size</command></term>
+ <listitem>
+ <para>
+ The maximum RSA exponent size, in bits, that will
+ be accepted when validating. Valid values are 35
+ to 4096 bits. The default zero (0) is also accepted
+ and is equivalent to 4096.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>prefetch</command></term>
+ <listitem>
+ <para>
+ When a query is received for cached data which
+ is to expire shortly, <command>named</command> can
+ refresh the data from the authoritative server
+ immediately, ensuring that the cache always has an
+ answer available.
+ </para>
+ <para>
+ The <option>prefetch</option> specifies the the
+ "trigger" TTL value at which prefetch of the current
+ query will take place: when a cache record with a
+ lower TTL value is encountered during query processing,
+ it will be refreshed. Valid trigger TTL values are 1 to
+ 10 seconds. Setting a trigger TTL to zero disables
+ prefetch.
+ </para>
+ <para>
+ An optional second argument can be used
+ to set the smallest <emphasis>original</emphasis>
+ TTL value that will be accepted for a record to be
+ eligible for prefetching. The difference between
+ the trigger TTL and the eligibility TTL must be
+ at least 6 seconds.
+ </para>
+ <para>
+ The default trigger and eligibility TTLs are
+ <literal>2</literal> and <literal>9</literal>,
+ respectively.
+ </para>
+ </listitem>
+ </varlistentry>
+ </variablelist>
+
+ </sect3>
+
+ <sect3 id="builtin">
+ <title>Built-in server information zones</title>
- </sect2>
- <sect2 id="managed-keys">
- <title><command>managed-keys</command> Statement Definition
- and Usage</title>
- <para>
- The <command>managed-keys</command> statement, like
- <command>trusted-keys</command>, defines DNSSEC
- security roots. The difference is that
- <command>managed-keys</command> can be kept up to date
- automatically, without intervention from the resolver
- operator.
- </para>
- <para>
- Suppose, for example, that a zone's key-signing
- key was compromised, and the zone owner had to revoke and
- replace the key. A resolver which had the old key in a
- <command>trusted-keys</command> statement would be
- unable to validate this zone any longer; it would
- reply with a SERVFAIL response code. This would
- continue until the resolver operator had updated the
- <command>trusted-keys</command> statement with the new key.
- </para>
- <para>
- If, however, the zone were listed in a
- <command>managed-keys</command> statement instead, then the
- zone owner could add a "stand-by" key to the zone in advance.
- <command>named</command> would store the stand-by key, and
- when the original key was revoked, <command>named</command>
- would be able to transition smoothly to the new key. It would
- also recognize that the old key had been revoked, and cease
- using that key to validate answers, minimizing the damage that
- the compromised key could do.
- </para>
- <para>
- A <command>managed-keys</command> statement contains a list of
- the keys to be managed, along with information about how the
- keys are to be initialized for the first time. The only
- initialization method currently supported (as of
- <acronym>BIND</acronym> 9.7.0) is <literal>initial-key</literal>.
- This means the <command>managed-keys</command> statement must
- contain a copy of the initializing key. (Future releases may
- allow keys to be initialized by other methods, eliminating this
- requirement.)
- </para>
- <para>
- Consequently, a <command>managed-keys</command> statement
- appears similar to a <command>trusted-keys</command>, differing
- in the presence of the second field, containing the keyword
- <literal>initial-key</literal>. The difference is, whereas the
- keys listed in a <command>trusted-keys</command> continue to be
- trusted until they are removed from
- <filename>named.conf</filename>, an initializing key listed
- in a <command>managed-keys</command> statement is only trusted
- <emphasis>once</emphasis>: for as long as it takes to load the
- managed key database and start the RFC 5011 key maintenance
- process.
- </para>
- <para>
- The first time <command>named</command> runs with a managed key
- configured in <filename>named.conf</filename>, it fetches the
- DNSKEY RRset directly from the zone apex, and validates it
- using the key specified in the <command>managed-keys</command>
- statement. If the DNSKEY RRset is validly signed, then it is
- used as the basis for a new managed keys database.
- </para>
- <para>
- From that point on, whenever <command>named</command> runs, it
- sees the <command>managed-keys</command> statement, checks to
- make sure RFC 5011 key maintenance has already been initialized
- for the specified domain, and if so, it simply moves on. The
- key specified in the <command>managed-keys</command> is not
- used to validate answers; it has been superseded by the key or
- keys stored in the managed keys database.
- </para>
- <para>
- The next time <command>named</command> runs after a name
- has been <emphasis>removed</emphasis> from the
- <command>managed-keys</command> statement, the corresponding
- zone will be removed from the managed keys database,
- and RFC 5011 key maintenance will no longer be used for that
- domain.
- </para>
<para>
- <command>named</command> only maintains a single managed keys
- database; consequently, unlike <command>trusted-keys</command>,
- <command>managed-keys</command> may only be set at the top
- level of <filename>named.conf</filename>, not within a view.
- </para>
- <para>
- In the current implementation, the managed keys database is
- stored as a master-format zone file called
- <filename>managed-keys.bind</filename>. When the key database
- is changed, the zone is updated. As with any other dynamic
- zone, changes will be written into a journal file,
- <filename>managed-keys.bind.jnl</filename>. They are committed
- to the master file as soon as possible afterward; in the case
- of the managed key database, this will usually occur within 30
- seconds. So, whenever <command>named</command> is using
- automatic key maintenance, those two files can be expected to
- exist in the working directory. (For this reason among others,
- the working directory should be always be writable by
- <command>named</command>.)
+ The server provides some helpful diagnostic information
+ through a number of built-in zones under the
+ pseudo-top-level-domain <literal>bind</literal> in the
+ <command>CHAOS</command> class. These zones are part
+ of a
+ built-in view (see <xref linkend="view_statement_grammar"/>) of
+ class
+ <command>CHAOS</command> which is separate from the
+ default view of class <command>IN</command>. Most global
+ configuration options (<command>allow-query</command>,
+ etc) will apply to this view, but some are locally
+ overridden: <command>notify</command>,
+ <command>recursion</command> and
+ <command>allow-new-zones</command> are
+ always set to <userinput>no</userinput>, and
+ <command>rate-limit</command> is set to allow
+ three responses per second.
</para>
<para>
- If the <command>dnssec-validation</command> option is
- set to <userinput>auto</userinput>, <command>named</command>
- will automatically initialize a managed key for the
- root zone. Similarly, if the <command>dnssec-lookaside</command>
- option is set to <userinput>auto</userinput>,
- <command>named</command> will automatically initialize
- a managed key for the zone <literal>dlv.isc.org</literal>.
- In both cases, the key that is used to initialize the key
- maintenance process is built into <command>named</command>,
- and can be overridden from <command>bindkeys-file</command>.
+ If you need to disable these zones, use the options
+ below, or hide the built-in <command>CHAOS</command>
+ view by
+ defining an explicit view of class <command>CHAOS</command>
+ that matches all clients.
</para>
- </sect2>
-
- <sect2 id="view_statement_grammar">
- <title><command>view</command> Statement Grammar</title>
-
-<programlisting><command>view</command> <replaceable>view_name</replaceable>
- <optional><replaceable>class</replaceable></optional> {
- match-clients { <replaceable>address_match_list</replaceable> };
- match-destinations { <replaceable>address_match_list</replaceable> };
- match-recursive-only <replaceable>yes_or_no</replaceable> ;
- <optional> <replaceable>view_option</replaceable>; ...</optional>
- <optional> <replaceable>zone_statement</replaceable>; ...</optional>
-};
-</programlisting>
-
- </sect2>
- <sect2>
- <title><command>view</command> Statement Definition and Usage</title>
-
- <para>
- The <command>view</command> statement is a powerful
- feature
- of <acronym>BIND</acronym> 9 that lets a name server
- answer a DNS query differently
- depending on who is asking. It is particularly useful for
- implementing
- split DNS setups without having to run multiple servers.
- </para>
-
- <para>
- Each <command>view</command> statement defines a view
- of the
- DNS namespace that will be seen by a subset of clients. A client
- matches
- a view if its source IP address matches the
- <varname>address_match_list</varname> of the view's
- <command>match-clients</command> clause and its
- destination IP address matches
- the <varname>address_match_list</varname> of the
- view's
- <command>match-destinations</command> clause. If not
- specified, both
- <command>match-clients</command> and <command>match-destinations</command>
- default to matching all addresses. In addition to checking IP
- addresses
- <command>match-clients</command> and <command>match-destinations</command>
- can also take <command>keys</command> which provide an
- mechanism for the
- client to select the view. A view can also be specified
- as <command>match-recursive-only</command>, which
- means that only recursive
- requests from matching clients will match that view.
- The order of the <command>view</command> statements is
- significant —
- a client request will be resolved in the context of the first
- <command>view</command> that it matches.
- </para>
-
- <para>
- Zones defined within a <command>view</command>
- statement will
- only be accessible to clients that match the <command>view</command>.
- By defining a zone of the same name in multiple views, different
- zone data can be given to different clients, for example,
- "internal"
- and "external" clients in a split DNS setup.
- </para>
-
- <para>
- Many of the options given in the <command>options</command> statement
- can also be used within a <command>view</command>
- statement, and then
- apply only when resolving queries with that view. When no
- view-specific
- value is given, the value in the <command>options</command> statement
- is used as a default. Also, zone options can have default values
- specified
- in the <command>view</command> statement; these
- view-specific defaults
- take precedence over those in the <command>options</command> statement.
- </para>
-
- <para>
- Views are class specific. If no class is given, class IN
- is assumed. Note that all non-IN views must contain a hint zone,
- since only the IN class has compiled-in default hints.
- </para>
-
- <para>
- If there are no <command>view</command> statements in
- the config
- file, a default view that matches any client is automatically
- created
- in class IN. Any <command>zone</command> statements
- specified on
- the top level of the configuration file are considered to be part
- of
- this default view, and the <command>options</command>
- statement will
- apply to the default view. If any explicit <command>view</command>
- statements are present, all <command>zone</command>
- statements must
- occur inside <command>view</command> statements.
- </para>
-
- <para>
- Here is an example of a typical split DNS setup implemented
- using <command>view</command> statements:
- </para>
-
-<programlisting>view "internal" {
- // This should match our internal networks.
- match-clients { 10.0.0.0/8; };
-
- // Provide recursive service to internal
- // clients only.
- recursion yes;
- // Provide a complete view of the example.com
- // zone including addresses of internal hosts.
- zone "example.com" {
- type master;
- file "example-internal.db";
- };
-};
+ <variablelist>
-view "external" {
- // Match all clients not matched by the
- // previous view.
- match-clients { any; };
+ <varlistentry>
+ <term><command>version</command></term>
+ <listitem>
+ <para>
+ The version the server should report
+ via a query of the name <literal>version.bind</literal>
+ with type <command>TXT</command>, class <command>CHAOS</command>.
+ The default is the real version number of this server.
+ Specifying <command>version none</command>
+ disables processing of the queries.
+ </para>
+ </listitem>
+ </varlistentry>
- // Refuse recursive service to external clients.
- recursion no;
+ <varlistentry>
+ <term><command>hostname</command></term>
+ <listitem>
+ <para>
+ The hostname the server should report via a query of
+ the name <filename>hostname.bind</filename>
+ with type <command>TXT</command>, class <command>CHAOS</command>.
+ This defaults to the hostname of the machine hosting the
+ name server as
+ found by the gethostname() function. The primary purpose of such queries
+ is to
+ identify which of a group of anycast servers is actually
+ answering your queries. Specifying <command>hostname none;</command>
+ disables processing of the queries.
+ </para>
+ </listitem>
+ </varlistentry>
- // Provide a restricted view of the example.com
- // zone containing only publicly accessible hosts.
- zone "example.com" {
- type master;
- file "example-external.db";
- };
-};
-</programlisting>
+ <varlistentry>
+ <term><command>server-id</command></term>
+ <listitem>
+ <para>
+ The ID the server should report when receiving a Name
+ Server Identifier (NSID) query, or a query of the name
+ <filename>ID.SERVER</filename> with type
+ <command>TXT</command>, class <command>CHAOS</command>.
+ The primary purpose of such queries is to
+ identify which of a group of anycast servers is actually
+ answering your queries. Specifying <command>server-id none;</command>
+ disables processing of the queries.
+ Specifying <command>server-id hostname;</command> will cause <command>named</command> to
+ use the hostname as found by the gethostname() function.
+ The default <command>server-id</command> is <command>none</command>.
+ </para>
+ </listitem>
+ </varlistentry>
- </sect2>
- <sect2 id="zone_statement_grammar">
- <title><command>zone</command>
- Statement Grammar</title>
+ </variablelist>
-<programlisting><command>zone</command> <replaceable>zone_name</replaceable> <optional><replaceable>class</replaceable></optional> {
- type master;
- <optional> allow-query { <replaceable>address_match_list</replaceable> }; </optional>
- <optional> allow-query-on { <replaceable>address_match_list</replaceable> }; </optional>
- <optional> allow-transfer { <replaceable>address_match_list</replaceable> }; </optional>
- <optional> allow-update { <replaceable>address_match_list</replaceable> }; </optional>
- <optional> update-check-ksk <replaceable>yes_or_no</replaceable>; </optional>
- <optional> dnssec-dnskey-kskonly <replaceable>yes_or_no</replaceable>; </optional>
- <optional> dnssec-loadkeys-interval <replaceable>number</replaceable>; </optional>
- <optional> update-policy <replaceable>local</replaceable> | { <replaceable>update_policy_rule</replaceable> <optional>...</optional> }; </optional>
- <optional> also-notify { <replaceable>ip_addr</replaceable> <optional>port <replaceable>ip_port</replaceable></optional> <optional>dscp <replaceable>ip_dscp</replaceable></optional> ;
- <optional> <replaceable>ip_addr</replaceable> <optional>port <replaceable>ip_port</replaceable></optional> <optional>dscp <replaceable>ip_dscp</replaceable></optional> ; ... </optional> }; </optional>
- <optional> check-names (<constant>warn</constant>|<constant>fail</constant>|<constant>ignore</constant>) ; </optional>
- <optional> check-mx (<constant>warn</constant>|<constant>fail</constant>|<constant>ignore</constant>) ; </optional>
- <optional> check-wildcard <replaceable>yes_or_no</replaceable>; </optional>
- <optional> check-spf ( <replaceable>warn</replaceable> | <replaceable>fail</replaceable> | <replaceable>ignore</replaceable> ); </optional>
- <optional> check-integrity <replaceable>yes_or_no</replaceable> ; </optional>
- <optional> dialup <replaceable>dialup_option</replaceable> ; </optional>
- <optional> file <replaceable>string</replaceable> ; </optional>
- <optional> masterfile-format (<constant>text</constant>|<constant>raw</constant>|<constant>map</constant>) ; </optional>
- <optional> journal <replaceable>string</replaceable> ; </optional>
- <optional> max-journal-size <replaceable>size_spec</replaceable>; </optional>
- <optional> forward (<constant>only</constant>|<constant>first</constant>) ; </optional>
- <optional> forwarders { <optional> <replaceable>ip_addr</replaceable> <optional>port <replaceable>ip_port</replaceable></optional> <optional>dscp <replaceable>ip_dscp</replaceable></optional> ; ... </optional> }; </optional>
- <optional> ixfr-base <replaceable>string</replaceable> ; </optional>
- <optional> ixfr-from-differences <replaceable>yes_or_no</replaceable>; </optional>
- <optional> ixfr-tmp-file <replaceable>string</replaceable> ; </optional>
- <optional> request-ixfr <replaceable>yes_or_no</replaceable> ; </optional>
- <optional> maintain-ixfr-base <replaceable>yes_or_no</replaceable> ; </optional>
- <optional> max-ixfr-log-size <replaceable>number</replaceable> ; </optional>
- <optional> max-transfer-idle-out <replaceable>number</replaceable> ; </optional>
- <optional> max-transfer-time-out <replaceable>number</replaceable> ; </optional>
- <optional> notify <replaceable>yes_or_no</replaceable> | <replaceable>explicit</replaceable> | <replaceable>master-only</replaceable> ; </optional>
- <optional> notify-delay <replaceable>seconds</replaceable> ; </optional>
- <optional> notify-to-soa <replaceable>yes_or_no</replaceable>; </optional>
- <optional> pubkey <replaceable>number</replaceable> <replaceable>number</replaceable> <replaceable>number</replaceable> <replaceable>string</replaceable> ; </optional>
- <optional> notify-source (<replaceable>ip4_addr</replaceable> | <constant>*</constant>) <optional>port <replaceable>ip_port</replaceable></optional> <optional>dscp <replaceable>ip_dscp</replaceable></optional> ; </optional>
- <optional> notify-source-v6 (<replaceable>ip6_addr</replaceable> | <constant>*</constant>) <optional>port <replaceable>ip_port</replaceable></optional> <optional>dscp <replaceable>ip_dscp</replaceable></optional> ; </optional>
- <optional> zone-statistics <replaceable>full</replaceable> | <replaceable>terse</replaceable> | <replaceable>none</replaceable>; </optional>
- <optional> sig-validity-interval <replaceable>number</replaceable> <optional><replaceable>number</replaceable></optional> ; </optional>
- <optional> sig-signing-nodes <replaceable>number</replaceable> ; </optional>
- <optional> sig-signing-signatures <replaceable>number</replaceable> ; </optional>
- <optional> sig-signing-type <replaceable>number</replaceable> ; </optional>
- <optional> database <replaceable>string</replaceable> ; </optional>
- <optional> min-refresh-time <replaceable>number</replaceable> ; </optional>
- <optional> max-refresh-time <replaceable>number</replaceable> ; </optional>
- <optional> min-retry-time <replaceable>number</replaceable> ; </optional>
- <optional> max-retry-time <replaceable>number</replaceable> ; </optional>
- <optional> key-directory <replaceable>path_name</replaceable>; </optional>
- <optional> auto-dnssec <constant>allow</constant>|<constant>maintain</constant>|<constant>off</constant>; </optional>
- <optional> inline-signing <replaceable>yes_or_no</replaceable>; </optional>
- <optional> zero-no-soa-ttl <replaceable>yes_or_no</replaceable> ; </optional>
- <optional> serial-update-method <constant>increment</constant>|<constant>unixtime</constant>; </optional>
-};
+ </sect3>
-zone <replaceable>zone_name</replaceable> <optional><replaceable>class</replaceable></optional> {
- type slave;
- <optional> allow-notify { <replaceable>address_match_list</replaceable> }; </optional>
- <optional> allow-query { <replaceable>address_match_list</replaceable> }; </optional>
- <optional> allow-query-on { <replaceable>address_match_list</replaceable> }; </optional>
- <optional> allow-transfer { <replaceable>address_match_list</replaceable> }; </optional>
- <optional> allow-update-forwarding { <replaceable>address_match_list</replaceable> }; </optional>
- <optional> dnssec-update-mode ( <replaceable>maintain</replaceable> | <replaceable>no-resign</replaceable> ); </optional>
- <optional> update-check-ksk <replaceable>yes_or_no</replaceable>; </optional>
- <optional> dnssec-dnskey-kskonly <replaceable>yes_or_no</replaceable>; </optional>
- <optional> dnssec-loadkeys-interval <replaceable>number</replaceable>; </optional>
- <optional> dnssec-secure-to-insecure <replaceable>yes_or_no</replaceable> ; </optional>
- <optional> try-tcp-refresh <replaceable>yes_or_no</replaceable>; </optional>
- <optional> also-notify <optional>port <replaceable>ip_port</replaceable></optional> <optional>dscp <replaceable>ip_dscp</replaceable></optional> { ( <replaceable>masters_list</replaceable> | <replaceable>ip_addr</replaceable>
- <optional>port <replaceable>ip_port</replaceable></optional>
- <optional>dscp <replaceable>ip_dscp</replaceable></optional>
- <optional>key <replaceable>key</replaceable></optional> ) ; <optional>...</optional> }; </optional>
- <optional> check-names (<constant>warn</constant>|<constant>fail</constant>|<constant>ignore</constant>) ; </optional>
- <optional> dialup <replaceable>dialup_option</replaceable> ; </optional>
- <optional> file <replaceable>string</replaceable> ; </optional>
- <optional> masterfile-format (<constant>text</constant>|<constant>raw</constant>|<constant>map</constant>) ; </optional>
- <optional> journal <replaceable>string</replaceable> ; </optional>
- <optional> max-journal-size <replaceable>size_spec</replaceable>; </optional>
- <optional> forward (<constant>only</constant>|<constant>first</constant>) ; </optional>
- <optional> forwarders { <optional> <replaceable>ip_addr</replaceable> <optional>port <replaceable>ip_port</replaceable></optional> <optional>dscp <replaceable>ip_dscp</replaceable></optional> ; ... </optional> }; </optional>
- <optional> ixfr-base <replaceable>string</replaceable> ; </optional>
- <optional> ixfr-from-differences <replaceable>yes_or_no</replaceable>; </optional>
- <optional> ixfr-tmp-file <replaceable>string</replaceable> ; </optional>
- <optional> maintain-ixfr-base <replaceable>yes_or_no</replaceable> ; </optional>
- <optional> masters <optional>port <replaceable>ip_port</replaceable></optional> <optional>dscp <replaceable>ip_dscp</replaceable></optional> { ( <replaceable>masters_list</replaceable> | <replaceable>ip_addr</replaceable>
- <optional>port <replaceable>ip_port</replaceable></optional>
- <optional>dscp <replaceable>ip_dscp</replaceable></optional>
- <optional>key <replaceable>key</replaceable></optional> ) ; <optional>...</optional> }; </optional>
- <optional> max-ixfr-log-size <replaceable>number</replaceable> ; </optional>
- <optional> max-transfer-idle-in <replaceable>number</replaceable> ; </optional>
- <optional> max-transfer-idle-out <replaceable>number</replaceable> ; </optional>
- <optional> max-transfer-time-in <replaceable>number</replaceable> ; </optional>
- <optional> max-transfer-time-out <replaceable>number</replaceable> ; </optional>
- <optional> notify <replaceable>yes_or_no</replaceable> | <replaceable>explicit</replaceable> | <replaceable>master-only</replaceable> ; </optional>
- <optional> notify-delay <replaceable>seconds</replaceable> ; </optional>
- <optional> notify-to-soa <replaceable>yes_or_no</replaceable>; </optional>
- <optional> pubkey <replaceable>number</replaceable> <replaceable>number</replaceable> <replaceable>number</replaceable> <replaceable>string</replaceable> ; </optional>
- <optional> transfer-source (<replaceable>ip4_addr</replaceable> | <constant>*</constant>) <optional>port <replaceable>ip_port</replaceable></optional> <optional>dscp <replaceable>ip_dscp</replaceable></optional> ; </optional>
- <optional> transfer-source-v6 (<replaceable>ip6_addr</replaceable> | <constant>*</constant>) <optional>port <replaceable>ip_port</replaceable></optional> <optional>dscp <replaceable>ip_dscp</replaceable></optional> ; </optional>
- <optional> alt-transfer-source (<replaceable>ip4_addr</replaceable> | <constant>*</constant>) <optional>port <replaceable>ip_port</replaceable></optional> <optional>dscp <replaceable>ip_dscp</replaceable></optional> ; </optional>
- <optional> alt-transfer-source-v6 (<replaceable>ip6_addr</replaceable> | <constant>*</constant>)
- <optional>port <replaceable>ip_port</replaceable></optional>
- <optional>dscp <replaceable>ip_dscp</replaceable></optional> ; </optional>
- <optional> use-alt-transfer-source <replaceable>yes_or_no</replaceable>; </optional>
- <optional> notify-source (<replaceable>ip4_addr</replaceable> | <constant>*</constant>) <optional>port <replaceable>ip_port</replaceable></optional> <optional>dscp <replaceable>ip_dscp</replaceable></optional> ; </optional>
- <optional> notify-source-v6 (<replaceable>ip6_addr</replaceable> | <constant>*</constant>) <optional>port <replaceable>ip_port</replaceable></optional> <optional>dscp <replaceable>ip_dscp</replaceable></optional> ; </optional>
- <optional> zone-statistics <replaceable>full</replaceable> | <replaceable>terse</replaceable> | <replaceable>none</replaceable>; </optional>
- <optional> sig-validity-interval <replaceable>number</replaceable> <optional><replaceable>number</replaceable></optional> ; </optional>
- <optional> sig-signing-nodes <replaceable>number</replaceable> ; </optional>
- <optional> sig-signing-signatures <replaceable>number</replaceable> ; </optional>
- <optional> sig-signing-type <replaceable>number</replaceable> ; </optional>
- <optional> database <replaceable>string</replaceable> ; </optional>
- <optional> min-refresh-time <replaceable>number</replaceable> ; </optional>
- <optional> max-refresh-time <replaceable>number</replaceable> ; </optional>
- <optional> min-retry-time <replaceable>number</replaceable> ; </optional>
- <optional> max-retry-time <replaceable>number</replaceable> ; </optional>
- <optional> key-directory <replaceable>path_name</replaceable>; </optional>
- <optional> auto-dnssec <constant>allow</constant>|<constant>maintain</constant>|<constant>off</constant>; </optional>
- <optional> inline-signing <replaceable>yes_or_no</replaceable>; </optional>
- <optional> multi-master <replaceable>yes_or_no</replaceable> ; </optional>
- <optional> zero-no-soa-ttl <replaceable>yes_or_no</replaceable> ; </optional>
-};
+ <sect3 id="empty">
+ <title>Built-in Empty Zones</title>
+ <para>
+ Named has some built-in empty zones (SOA and NS records only).
+ These are for zones that should normally be answered locally
+ and which queries should not be sent to the Internet's root
+ servers. The official servers which cover these namespaces
+ return NXDOMAIN responses to these queries. In particular,
+ these cover the reverse namespaces for addresses from
+ RFC 1918, RFC 4193, RFC 5737 and RFC 6598. They also include the
+ reverse namespace for IPv6 local address (locally assigned),
+ IPv6 link local addresses, the IPv6 loopback address and the
+ IPv6 unknown address.
+ </para>
+ <para>
+ Named will attempt to determine if a built-in zone already exists
+ or is active (covered by a forward-only forwarding declaration)
+ and will not create an empty zone in that case.
+ </para>
+ <para>
+ The current list of empty zones is:
+ <itemizedlist>
+ <listitem>10.IN-ADDR.ARPA</listitem>
+ <listitem>16.172.IN-ADDR.ARPA</listitem>
+ <listitem>17.172.IN-ADDR.ARPA</listitem>
+ <listitem>18.172.IN-ADDR.ARPA</listitem>
+ <listitem>19.172.IN-ADDR.ARPA</listitem>
+ <listitem>20.172.IN-ADDR.ARPA</listitem>
+ <listitem>21.172.IN-ADDR.ARPA</listitem>
+ <listitem>22.172.IN-ADDR.ARPA</listitem>
+ <listitem>23.172.IN-ADDR.ARPA</listitem>
+ <listitem>24.172.IN-ADDR.ARPA</listitem>
+ <listitem>25.172.IN-ADDR.ARPA</listitem>
+ <listitem>26.172.IN-ADDR.ARPA</listitem>
+ <listitem>27.172.IN-ADDR.ARPA</listitem>
+ <listitem>28.172.IN-ADDR.ARPA</listitem>
+ <listitem>29.172.IN-ADDR.ARPA</listitem>
+ <listitem>30.172.IN-ADDR.ARPA</listitem>
+ <listitem>31.172.IN-ADDR.ARPA</listitem>
+ <listitem>168.192.IN-ADDR.ARPA</listitem>
+ <listitem>64.100.IN-ADDR.ARPA</listitem>
+ <listitem>65.100.IN-ADDR.ARPA</listitem>
+ <listitem>66.100.IN-ADDR.ARPA</listitem>
+ <listitem>67.100.IN-ADDR.ARPA</listitem>
+ <listitem>68.100.IN-ADDR.ARPA</listitem>
+ <listitem>69.100.IN-ADDR.ARPA</listitem>
+ <listitem>70.100.IN-ADDR.ARPA</listitem>
+ <listitem>71.100.IN-ADDR.ARPA</listitem>
+ <listitem>72.100.IN-ADDR.ARPA</listitem>
+ <listitem>73.100.IN-ADDR.ARPA</listitem>
+ <listitem>74.100.IN-ADDR.ARPA</listitem>
+ <listitem>75.100.IN-ADDR.ARPA</listitem>
+ <listitem>76.100.IN-ADDR.ARPA</listitem>
+ <listitem>77.100.IN-ADDR.ARPA</listitem>
+ <listitem>78.100.IN-ADDR.ARPA</listitem>
+ <listitem>79.100.IN-ADDR.ARPA</listitem>
+ <listitem>80.100.IN-ADDR.ARPA</listitem>
+ <listitem>81.100.IN-ADDR.ARPA</listitem>
+ <listitem>82.100.IN-ADDR.ARPA</listitem>
+ <listitem>83.100.IN-ADDR.ARPA</listitem>
+ <listitem>84.100.IN-ADDR.ARPA</listitem>
+ <listitem>85.100.IN-ADDR.ARPA</listitem>
+ <listitem>86.100.IN-ADDR.ARPA</listitem>
+ <listitem>87.100.IN-ADDR.ARPA</listitem>
+ <listitem>88.100.IN-ADDR.ARPA</listitem>
+ <listitem>89.100.IN-ADDR.ARPA</listitem>
+ <listitem>90.100.IN-ADDR.ARPA</listitem>
+ <listitem>91.100.IN-ADDR.ARPA</listitem>
+ <listitem>92.100.IN-ADDR.ARPA</listitem>
+ <listitem>93.100.IN-ADDR.ARPA</listitem>
+ <listitem>94.100.IN-ADDR.ARPA</listitem>
+ <listitem>95.100.IN-ADDR.ARPA</listitem>
+ <listitem>96.100.IN-ADDR.ARPA</listitem>
+ <listitem>97.100.IN-ADDR.ARPA</listitem>
+ <listitem>98.100.IN-ADDR.ARPA</listitem>
+ <listitem>99.100.IN-ADDR.ARPA</listitem>
+ <listitem>100.100.IN-ADDR.ARPA</listitem>
+ <listitem>101.100.IN-ADDR.ARPA</listitem>
+ <listitem>102.100.IN-ADDR.ARPA</listitem>
+ <listitem>103.100.IN-ADDR.ARPA</listitem>
+ <listitem>104.100.IN-ADDR.ARPA</listitem>
+ <listitem>105.100.IN-ADDR.ARPA</listitem>
+ <listitem>106.100.IN-ADDR.ARPA</listitem>
+ <listitem>107.100.IN-ADDR.ARPA</listitem>
+ <listitem>108.100.IN-ADDR.ARPA</listitem>
+ <listitem>109.100.IN-ADDR.ARPA</listitem>
+ <listitem>110.100.IN-ADDR.ARPA</listitem>
+ <listitem>111.100.IN-ADDR.ARPA</listitem>
+ <listitem>112.100.IN-ADDR.ARPA</listitem>
+ <listitem>113.100.IN-ADDR.ARPA</listitem>
+ <listitem>114.100.IN-ADDR.ARPA</listitem>
+ <listitem>115.100.IN-ADDR.ARPA</listitem>
+ <listitem>116.100.IN-ADDR.ARPA</listitem>
+ <listitem>117.100.IN-ADDR.ARPA</listitem>
+ <listitem>118.100.IN-ADDR.ARPA</listitem>
+ <listitem>119.100.IN-ADDR.ARPA</listitem>
+ <listitem>120.100.IN-ADDR.ARPA</listitem>
+ <listitem>121.100.IN-ADDR.ARPA</listitem>
+ <listitem>122.100.IN-ADDR.ARPA</listitem>
+ <listitem>123.100.IN-ADDR.ARPA</listitem>
+ <listitem>124.100.IN-ADDR.ARPA</listitem>
+ <listitem>125.100.IN-ADDR.ARPA</listitem>
+ <listitem>126.100.IN-ADDR.ARPA</listitem>
+ <listitem>127.100.IN-ADDR.ARPA</listitem>
+ <listitem>0.IN-ADDR.ARPA</listitem>
+ <listitem>127.IN-ADDR.ARPA</listitem>
+ <listitem>254.169.IN-ADDR.ARPA</listitem>
+ <listitem>2.0.192.IN-ADDR.ARPA</listitem>
+ <listitem>100.51.198.IN-ADDR.ARPA</listitem>
+ <listitem>113.0.203.IN-ADDR.ARPA</listitem>
+ <listitem>255.255.255.255.IN-ADDR.ARPA</listitem>
+ <listitem>0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.IP6.ARPA</listitem>
+ <listitem>1.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.IP6.ARPA</listitem>
+ <listitem>8.B.D.0.1.0.0.2.IP6.ARPA</listitem>
+ <listitem>D.F.IP6.ARPA</listitem>
+ <listitem>8.E.F.IP6.ARPA</listitem>
+ <listitem>9.E.F.IP6.ARPA</listitem>
+ <listitem>A.E.F.IP6.ARPA</listitem>
+ <listitem>B.E.F.IP6.ARPA</listitem>
+ </itemizedlist>
+ </para>
+ <para>
+ Empty zones are settable at the view level and only apply to
+ views of class IN. Disabled empty zones are only inherited
+ from options if there are no disabled empty zones specified
+ at the view level. To override the options list of disabled
+ zones, you can disable the root zone at the view level, for example:
+<programlisting>
+ disable-empty-zone ".";
+</programlisting>
+ </para>
+ <para>
+ If you are using the address ranges covered here, you should
+ already have reverse zones covering the addresses you use.
+ In practice this appears to not be the case with many queries
+ being made to the infrastructure servers for names in these
+ spaces. So many in fact that sacrificial servers were needed
+ to be deployed to channel the query load away from the
+ infrastructure servers.
+ </para>
+ <note>
+ The real parent servers for these zones should disable all
+ empty zone under the parent zone they serve. For the real
+ root servers, this is all built-in empty zones. This will
+ enable them to return referrals to deeper in the tree.
+ </note>
+ <variablelist>
+ <varlistentry>
+ <term><command>empty-server</command></term>
+ <listitem>
+ <para>
+ Specify what server name will appear in the returned
+ SOA record for empty zones. If none is specified, then
+ the zone's name will be used.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>empty-contact</command></term>
+ <listitem>
+ <para>
+ Specify what contact name will appear in the returned
+ SOA record for empty zones. If none is specified, then
+ "." will be used.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>empty-zones-enable</command></term>
+ <listitem>
+ <para>
+ Enable or disable all empty zones. By default, they
+ are enabled.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>disable-empty-zone</command></term>
+ <listitem>
+ <para>
+ Disable individual empty zones. By default, none are
+ disabled. This option can be specified multiple times.
+ </para>
+ </listitem>
+ </varlistentry>
+ </variablelist>
+ </sect3>
-zone <replaceable>zone_name</replaceable> <optional><replaceable>class</replaceable></optional> {
- type hint;
- file <replaceable>string</replaceable> ;
- <optional> delegation-only <replaceable>yes_or_no</replaceable> ; </optional>
- <optional> check-names (<constant>warn</constant>|<constant>fail</constant>|<constant>ignore</constant>) ; </optional> // Not Implemented.
-};
+ <sect3 id="acache">
+ <title>Additional Section Caching</title>
-zone <replaceable>zone_name</replaceable> <optional><replaceable>class</replaceable></optional> {
- type stub;
- <optional> allow-query { <replaceable>address_match_list</replaceable> }; </optional>
- <optional> allow-query-on { <replaceable>address_match_list</replaceable> }; </optional>
- <optional> check-names (<constant>warn</constant>|<constant>fail</constant>|<constant>ignore</constant>) ; </optional>
- <optional> dialup <replaceable>dialup_option</replaceable> ; </optional>
- <optional> delegation-only <replaceable>yes_or_no</replaceable> ; </optional>
- <optional> file <replaceable>string</replaceable> ; </optional>
- <optional> masterfile-format (<constant>text</constant>|<constant>raw</constant>|<constant>map</constant>) ; </optional>
- <optional> forward (<constant>only</constant>|<constant>first</constant>) ; </optional>
- <optional> forwarders { <optional> <replaceable>ip_addr</replaceable> <optional>port <replaceable>ip_port</replaceable></optional> <optional>dscp <replaceable>ip_dscp</replaceable></optional> ; ... </optional> }; </optional>
- <optional> masters <optional>port <replaceable>ip_port</replaceable></optional> <optional>dscp <replaceable>ip_dscp</replaceable></optional> { ( <replaceable>masters_list</replaceable> | <replaceable>ip_addr</replaceable>
- <optional>port <replaceable>ip_port</replaceable></optional>
- <optional>dscp <replaceable>ip_dscp</replaceable></optional>
- <optional>key <replaceable>key</replaceable></optional> ) ; <optional>...</optional> }; </optional>
- <optional> max-transfer-idle-in <replaceable>number</replaceable> ; </optional>
- <optional> max-transfer-time-in <replaceable>number</replaceable> ; </optional>
- <optional> pubkey <replaceable>number</replaceable> <replaceable>number</replaceable> <replaceable>number</replaceable> <replaceable>string</replaceable> ; </optional>
- <optional> transfer-source (<replaceable>ip4_addr</replaceable> | <constant>*</constant>) <optional>port <replaceable>ip_port</replaceable></optional> <optional>dscp <replaceable>ip_dscp</replaceable></optional> ; </optional>
- <optional> transfer-source-v6 (<replaceable>ip6_addr</replaceable> | <constant>*</constant>)
- <optional>port <replaceable>ip_port</replaceable></optional> <optional>dscp <replaceable>ip_dscp</replaceable></optional> ; </optional>
- <optional> alt-transfer-source (<replaceable>ip4_addr</replaceable> | <constant>*</constant>) <optional>port <replaceable>ip_port</replaceable></optional> <optional>dscp <replaceable>ip_dscp</replaceable></optional> ; </optional>
- <optional> alt-transfer-source-v6 (<replaceable>ip6_addr</replaceable> | <constant>*</constant>)
- <optional>port <replaceable>ip_port</replaceable></optional> <optional>dscp <replaceable>ip_dscp</replaceable></optional> ; </optional>
- <optional> use-alt-transfer-source <replaceable>yes_or_no</replaceable>; </optional>
- <optional> zone-statistics <replaceable>yes_or_no</replaceable> ; </optional>
- <optional> database <replaceable>string</replaceable> ; </optional>
- <optional> min-refresh-time <replaceable>number</replaceable> ; </optional>
- <optional> max-refresh-time <replaceable>number</replaceable> ; </optional>
- <optional> min-retry-time <replaceable>number</replaceable> ; </optional>
- <optional> max-retry-time <replaceable>number</replaceable> ; </optional>
- <optional> multi-master <replaceable>yes_or_no</replaceable> ; </optional>
-};
+ <para>
+ The additional section cache, also called <command>acache</command>,
+ is an internal cache to improve the response performance of BIND 9.
+ When additional section caching is enabled, BIND 9 will
+ cache an internal short-cut to the additional section content for
+ each answer RR.
+ Note that <command>acache</command> is an internal caching
+ mechanism of BIND 9, and is not related to the DNS caching
+ server function.
+ </para>
-zone <replaceable>zone_name</replaceable> <optional><replaceable>class</replaceable></optional> {
- type static-stub;
- <optional> allow-query { <replaceable>address_match_list</replaceable> }; </optional>
- <optional> server-addresses { <optional> <replaceable>ip_addr</replaceable> ; ... </optional> }; </optional>
- <optional> server-names { <optional> <replaceable>namelist</replaceable> </optional> }; </optional>
- <optional> zone-statistics <replaceable>yes_or_no</replaceable> ; </optional>
-};
+ <para>
+ Additional section caching does not change the
+ response content (except the RRsets ordering of the additional
+ section, see below), but can improve the response performance
+ significantly.
+ It is particularly effective when BIND 9 acts as an authoritative
+ server for a zone that has many delegations with many glue RRs.
+ </para>
-zone <replaceable>zone_name</replaceable> <optional><replaceable>class</replaceable></optional> {
- type forward;
- <optional> forward (<constant>only</constant>|<constant>first</constant>) ; </optional>
- <optional> forwarders { <optional> <replaceable>ip_addr</replaceable> <optional>port <replaceable>ip_port</replaceable></optional> <optional>dscp <replaceable>ip_dscp</replaceable></optional> ; ... </optional> }; </optional>
- <optional> delegation-only <replaceable>yes_or_no</replaceable> ; </optional>
-};
+ <para>
+ In order to obtain the maximum performance improvement
+ from additional section caching, setting
+ <command>additional-from-cache</command>
+ to <command>no</command> is recommended, since the current
+ implementation of <command>acache</command>
+ does not short-cut of additional section information from the
+ DNS cache data.
+ </para>
-zone <replaceable>"."</replaceable> <optional><replaceable>class</replaceable></optional> {
- type redirect;
- file <replaceable>string</replaceable> ;
- <optional> masterfile-format (<constant>text</constant>|<constant>raw</constant>|<constant>map</constant>) ; </optional>
- <optional> allow-query { <replaceable>address_match_list</replaceable> }; </optional>
-};
+ <para>
+ One obvious disadvantage of <command>acache</command> is
+ that it requires much more
+ memory for the internal cached data.
+ Thus, if the response performance does not matter and memory
+ consumption is much more critical, the
+ <command>acache</command> mechanism can be
+ disabled by setting <command>acache-enable</command> to
+ <command>no</command>.
+ It is also possible to specify the upper limit of memory
+ consumption
+ for acache by using <command>max-acache-size</command>.
+ </para>
-zone <replaceable>zone_name</replaceable> <optional><replaceable>class</replaceable></optional> {
- type delegation-only;
-};
+ <para>
+ Additional section caching also has a minor effect on the
+ RRset ordering in the additional section.
+ Without <command>acache</command>,
+ <command>cyclic</command> order is effective for the additional
+ section as well as the answer and authority sections.
+ However, additional section caching fixes the ordering when it
+ first caches an RRset for the additional section, and the same
+ ordering will be kept in succeeding responses, regardless of the
+ setting of <command>rrset-order</command>.
+ The effect of this should be minor, however, since an
+ RRset in the additional section
+ typically only contains a small number of RRs (and in many cases
+ it only contains a single RR), in which case the
+ ordering does not matter much.
+ </para>
-zone <replaceable>zone_name</replaceable> <optional><replaceable>class</replaceable></optional> {
- <optional> in-view <replaceable>string</replaceable> ; </optional>
-};
+ <para>
+ The following is a summary of options related to
+ <command>acache</command>.
+ </para>
-</programlisting>
+ <variablelist>
- </sect2>
- <sect2>
- <title><command>zone</command> Statement Definition and Usage</title>
- <sect3>
- <title>Zone Types</title>
- <informaltable colsep="0" rowsep="0">
- <tgroup cols="2" colsep="0" rowsep="0" tgroupstyle="3Level-table">
- <!--colspec colname="1" colnum="1" colsep="0" colwidth="1.108in"/-->
- <!--colspec colname="2" colnum="2" colsep="0" colwidth="4.017in"/-->
- <colspec colname="1" colnum="1" colsep="0"/>
- <colspec colname="2" colnum="2" colsep="0" colwidth="4.017in"/>
- <tbody>
- <row rowsep="0">
- <entry colname="1">
- <para>
- <varname>master</varname>
- </para>
- </entry>
- <entry colname="2">
- <para>
- The server has a master copy of the data
- for the zone and will be able to provide authoritative
- answers for
- it.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para>
- <varname>slave</varname>
- </para>
- </entry>
- <entry colname="2">
- <para>
- A slave zone is a replica of a master
- zone. The <command>masters</command> list
- specifies one or more IP addresses
- of master servers that the slave contacts to update
- its copy of the zone.
- Masters list elements can also be names of other
- masters lists.
- By default, transfers are made from port 53 on the
- servers; this can
- be changed for all servers by specifying a port number
- before the
- list of IP addresses, or on a per-server basis after
- the IP address.
- Authentication to the master can also be done with
- per-server TSIG keys.
- If a file is specified, then the
- replica will be written to this file whenever the zone
- is changed,
- and reloaded from this file on a server restart. Use
- of a file is
- recommended, since it often speeds server startup and
- eliminates
- a needless waste of bandwidth. Note that for large
- numbers (in the
- tens or hundreds of thousands) of zones per server, it
- is best to
- use a two-level naming scheme for zone filenames. For
- example,
- a slave server for the zone <literal>example.com</literal> might place
- the zone contents into a file called
- <filename>ex/example.com</filename> where <filename>ex/</filename> is
- just the first two letters of the zone name. (Most
- operating systems
- behave very slowly if you put 100000 files into
- a single directory.)
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para>
- <varname>stub</varname>
- </para>
- </entry>
- <entry colname="2">
- <para>
- A stub zone is similar to a slave zone,
- except that it replicates only the NS records of a
- master zone instead
- of the entire zone. Stub zones are not a standard part
- of the DNS;
- they are a feature specific to the <acronym>BIND</acronym> implementation.
- </para>
-
- <para>
- Stub zones can be used to eliminate the need for glue
- NS record
- in a parent zone at the expense of maintaining a stub
- zone entry and
- a set of name server addresses in <filename>named.conf</filename>.
- This usage is not recommended for new configurations,
- and BIND 9
- supports it only in a limited way.
- In <acronym>BIND</acronym> 4/8, zone
- transfers of a parent zone
- included the NS records from stub children of that
- zone. This meant
- that, in some cases, users could get away with
- configuring child stubs
- only in the master server for the parent zone. <acronym>BIND</acronym>
- 9 never mixes together zone data from different zones
- in this
- way. Therefore, if a <acronym>BIND</acronym> 9 master serving a parent
- zone has child stub zones configured, all the slave
- servers for the
- parent zone also need to have the same child stub
- zones
- configured.
- </para>
-
- <para>
- Stub zones can also be used as a way of forcing the
- resolution
- of a given domain to use a particular set of
- authoritative servers.
- For example, the caching name servers on a private
- network using
- RFC1918 addressing may be configured with stub zones
- for
- <literal>10.in-addr.arpa</literal>
- to use a set of internal name servers as the
- authoritative
- servers for that domain.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para>
- <varname>static-stub</varname>
- </para>
- </entry>
- <entry colname="2">
- <para>
- A static-stub zone is similar to a stub zone
- with the following exceptions:
- the zone data is statically configured, rather
- than transferred from a master server;
- when recursion is necessary for a query that
- matches a static-stub zone, the locally
- configured data (nameserver names and glue addresses)
- is always used even if different authoritative
- information is cached.
- </para>
- <para>
- Zone data is configured via the
- <command>server-addresses</command> and
- <command>server-names</command> zone options.
- </para>
- <para>
- The zone data is maintained in the form of NS
- and (if necessary) glue A or AAAA RRs
- internally, which can be seen by dumping zone
- databases by <command>rndc dumpdb -all</command>.
- The configured RRs are considered local configuration
- parameters rather than public data.
- Non recursive queries (i.e., those with the RD
- bit off) to a static-stub zone are therefore
- prohibited and will be responded with REFUSED.
- </para>
- <para>
- Since the data is statically configured, no
- zone maintenance action takes place for a static-stub
- zone.
- For example, there is no periodic refresh
- attempt, and an incoming notify message
- will be rejected with an rcode of NOTAUTH.
- </para>
- <para>
- Each static-stub zone is configured with
- internally generated NS and (if necessary)
- glue A or AAAA RRs
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para>
- <varname>forward</varname>
- </para>
- </entry>
- <entry colname="2">
- <para>
- A "forward zone" is a way to configure
- forwarding on a per-domain basis. A <command>zone</command> statement
- of type <command>forward</command> can
- contain a <command>forward</command>
- and/or <command>forwarders</command>
- statement,
- which will apply to queries within the domain given by
- the zone
- name. If no <command>forwarders</command>
- statement is present or
- an empty list for <command>forwarders</command> is given, then no
- forwarding will be done for the domain, canceling the
- effects of
- any forwarders in the <command>options</command> statement. Thus
- if you want to use this type of zone to change the
- behavior of the
- global <command>forward</command> option
- (that is, "forward first"
- to, then "forward only", or vice versa, but want to
- use the same
- servers as set globally) you need to re-specify the
- global forwarders.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para>
- <varname>hint</varname>
- </para>
- </entry>
- <entry colname="2">
- <para>
- The initial set of root name servers is
- specified using a "hint zone". When the server starts
- up, it uses
- the root hints to find a root name server and get the
- most recent
- list of root name servers. If no hint zone is
- specified for class
- IN, the server uses a compiled-in default set of root
- servers hints.
- Classes other than IN have no built-in defaults hints.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para>
- <varname>redirect</varname>
- </para>
- </entry>
- <entry colname="2">
- <para>
- Redirect zones are used to provide answers to
- queries when normal resolution would result in
- NXDOMAIN being returned.
- Only one redirect zone is supported
- per view. <command>allow-query</command> can be
- used to restrict which clients see these answers.
- </para>
- <para>
- If the client has requested DNSSEC records (DO=1) and
- the NXDOMAIN response is signed then no substitution
- will occur.
- </para>
- <para>
- To redirect all NXDOMAIN responses to
- 100.100.100.2 and
- 2001:ffff:ffff::100.100.100.2, one would
- configure a type redirect zone named ".",
- with the zone file containing wildcard records
- that point to the desired addresses:
- <literal>"*. IN A 100.100.100.2"</literal>
- and
- <literal>"*. IN AAAA 2001:ffff:ffff::100.100.100.2"</literal>.
- </para>
- <para>
- To redirect all Spanish names (under .ES) one
- would use similar entries but with the names
- "*.ES." instead of "*.". To redirect all
- commercial Spanish names (under COM.ES) one
- would use wildcard entries called "*.COM.ES.".
- </para>
- <para>
- Note that the redirect zone supports all
- possible types; it is not limited to A and
- AAAA records.
- </para>
- <para>
- Because redirect zones are not referenced
- directly by name, they are not kept in the
- zone lookup table with normal master and slave
- zones. Consequently, it is not currently possible
- to use
- <command>rndc reload
- <replaceable>zonename</replaceable></command>
- to reload a redirect zone. However, when using
- <command>rndc reload</command> without specifying
- a zone name, redirect zones will be reloaded along
- with other zones.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para>
- <varname>delegation-only</varname>
- </para>
- </entry>
- <entry colname="2">
- <para>
- This is used to enforce the delegation-only
- status of infrastructure zones (e.g. COM,
- NET, ORG). Any answer that is received
- without an explicit or implicit delegation
- in the authority section will be treated
- as NXDOMAIN. This does not apply to the
- zone apex. This should not be applied to
- leaf zones.
- </para>
- <para>
- <varname>delegation-only</varname> has no
- effect on answers received from forwarders.
- </para>
- <para>
- See caveats in <xref linkend="root_delegation_only"/>.
- </para>
- </entry>
- </row>
- </tbody>
- </tgroup>
- </informaltable>
- </sect3>
-
- <sect3>
- <title>Class</title>
- <para>
- The zone's name may optionally be followed by a class. If
- a class is not specified, class <literal>IN</literal> (for <varname>Internet</varname>),
- is assumed. This is correct for the vast majority of cases.
- </para>
- <para>
- The <literal>hesiod</literal> class is
- named for an information service from MIT's Project Athena. It
- is
- used to share information about various systems databases, such
- as users, groups, printers and so on. The keyword
- <literal>HS</literal> is
- a synonym for hesiod.
- </para>
- <para>
- Another MIT development is Chaosnet, a LAN protocol created
- in the mid-1970s. Zone data for it can be specified with the <literal>CHAOS</literal> class.
- </para>
- </sect3>
-
- <sect3>
- <title>Zone Options</title>
-
- <variablelist>
-
- <varlistentry>
- <term><command>allow-notify</command></term>
- <listitem>
- <para>
- See the description of
- <command>allow-notify</command> in <xref linkend="access_control"/>.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>allow-query</command></term>
- <listitem>
- <para>
- See the description of
- <command>allow-query</command> in <xref linkend="access_control"/>.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>allow-query-on</command></term>
- <listitem>
- <para>
- See the description of
- <command>allow-query-on</command> in <xref linkend="access_control"/>.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>allow-transfer</command></term>
- <listitem>
- <para>
- See the description of <command>allow-transfer</command>
- in <xref linkend="access_control"/>.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>allow-update</command></term>
- <listitem>
- <para>
- See the description of <command>allow-update</command>
- in <xref linkend="access_control"/>.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>update-policy</command></term>
- <listitem>
- <para>
- Specifies a "Simple Secure Update" policy. See
- <xref linkend="dynamic_update_policies"/>.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>allow-update-forwarding</command></term>
- <listitem>
- <para>
- See the description of <command>allow-update-forwarding</command>
- in <xref linkend="access_control"/>.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>also-notify</command></term>
- <listitem>
- <para>
- Only meaningful if <command>notify</command>
- is
- active for this zone. The set of machines that will
- receive a
- <literal>DNS NOTIFY</literal> message
- for this zone is made up of all the listed name servers
- (other than
- the primary master) for the zone plus any IP addresses
- specified
- with <command>also-notify</command>. A port
- may be specified
- with each <command>also-notify</command>
- address to send the notify
- messages to a port other than the default of 53.
- A TSIG key may also be specified to cause the
- <literal>NOTIFY</literal> to be signed by the
- given key.
- <command>also-notify</command> is not
- meaningful for stub zones.
- The default is the empty list.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>check-names</command></term>
- <listitem>
- <para>
- This option is used to restrict the character set and
- syntax of
- certain domain names in master files and/or DNS responses
- received from the
- network. The default varies according to zone type. For <command>master</command> zones the default is <command>fail</command>. For <command>slave</command>
- zones the default is <command>warn</command>.
- It is not implemented for <command>hint</command> zones.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>check-mx</command></term>
- <listitem>
- <para>
- See the description of
- <command>check-mx</command> in <xref linkend="boolean_options"/>.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>check-spf</command></term>
- <listitem>
- <para>
- See the description of
- <command>check-spf</command> in <xref linkend="boolean_options"/>.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>check-wildcard</command></term>
- <listitem>
- <para>
- See the description of
- <command>check-wildcard</command> in <xref linkend="boolean_options"/>.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>check-integrity</command></term>
- <listitem>
- <para>
- See the description of
- <command>check-integrity</command> in <xref linkend="boolean_options"/>.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>check-sibling</command></term>
- <listitem>
- <para>
- See the description of
- <command>check-sibling</command> in <xref linkend="boolean_options"/>.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>zero-no-soa-ttl</command></term>
- <listitem>
- <para>
- See the description of
- <command>zero-no-soa-ttl</command> in <xref linkend="boolean_options"/>.
- </para>
- </listitem>
- </varlistentry>
+ <varlistentry>
+ <term><command>acache-enable</command></term>
+ <listitem>
+ <para>
+ If <command>yes</command>, additional section caching is
+ enabled. The default value is <command>no</command>.
+ </para>
+ </listitem>
+ </varlistentry>
- <varlistentry>
- <term><command>update-check-ksk</command></term>
- <listitem>
- <para>
- See the description of
- <command>update-check-ksk</command> in <xref linkend="boolean_options"/>.
- </para>
- </listitem>
- </varlistentry>
+ <varlistentry>
+ <term><command>acache-cleaning-interval</command></term>
+ <listitem>
+ <para>
+ The server will remove stale cache entries, based on an LRU
+ based
+ algorithm, every <command>acache-cleaning-interval</command> minutes.
+ The default is 60 minutes.
+ If set to 0, no periodic cleaning will occur.
+ </para>
+ </listitem>
+ </varlistentry>
- <varlistentry>
- <term><command>dnssec-update-mode</command></term>
- <listitem>
- <para>
- See the description of
- <command>dnssec-update-mode</command> in <xref linkend="options"/>.
- </para>
- </listitem>
- </varlistentry>
+ <varlistentry>
+ <term><command>max-acache-size</command></term>
+ <listitem>
+ <para>
+ The maximum amount of memory in bytes to use for the server's acache.
+ When the amount of data in the acache reaches this limit,
+ the server
+ will clean more aggressively so that the limit is not
+ exceeded.
+ In a server with multiple views, the limit applies
+ separately to the
+ acache of each view.
+ The default is <literal>16M</literal>.
+ </para>
+ </listitem>
+ </varlistentry>
- <varlistentry>
- <term><command>dnssec-dnskey-kskonly</command></term>
- <listitem>
- <para>
- See the description of
- <command>dnssec-dnskey-kskonly</command> in <xref linkend="boolean_options"/>.
- </para>
- </listitem>
- </varlistentry>
+ </variablelist>
- <varlistentry>
- <term><command>try-tcp-refresh</command></term>
- <listitem>
- <para>
- See the description of
- <command>try-tcp-refresh</command> in <xref linkend="boolean_options"/>.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>database</command></term>
- <listitem>
- <para>
- Specify the type of database to be used for storing the
- zone data. The string following the <command>database</command> keyword
- is interpreted as a list of whitespace-delimited words.
- The first word
- identifies the database type, and any subsequent words are
- passed
- as arguments to the database to be interpreted in a way
- specific
- to the database type.
- </para>
- <para>
- The default is <userinput>"rbt"</userinput>, BIND 9's
- native in-memory
- red-black-tree database. This database does not take
- arguments.
- </para>
- <para>
- Other values are possible if additional database drivers
- have been linked into the server. Some sample drivers are
- included
- with the distribution but none are linked in by default.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>dialup</command></term>
- <listitem>
- <para>
- See the description of
- <command>dialup</command> in <xref linkend="boolean_options"/>.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>delegation-only</command></term>
- <listitem>
- <para>
- The flag only applies to hint and stub zones. If set
- to <userinput>yes</userinput>, then the zone will also be
- treated as if it is also a delegation-only type zone.
- </para>
- <para>
- See caveats in <xref linkend="root_delegation_only"/>.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>forward</command></term>
- <listitem>
- <para>
- Only meaningful if the zone has a forwarders
- list. The <command>only</command> value causes
- the lookup to fail
- after trying the forwarders and getting no answer, while <command>first</command> would
- allow a normal lookup to be tried.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>forwarders</command></term>
- <listitem>
- <para>
- Used to override the list of global forwarders.
- If it is not specified in a zone of type <command>forward</command>,
- no forwarding is done for the zone and the global options are
- not used.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>ixfr-base</command></term>
- <listitem>
- <para>
- Was used in <acronym>BIND</acronym> 8 to
- specify the name
- of the transaction log (journal) file for dynamic update
- and IXFR.
- <acronym>BIND</acronym> 9 ignores the option
- and constructs the name of the journal
- file by appending "<filename>.jnl</filename>"
- to the name of the
- zone file.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>ixfr-tmp-file</command></term>
- <listitem>
- <para>
- Was an undocumented option in <acronym>BIND</acronym> 8.
- Ignored in <acronym>BIND</acronym> 9.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>journal</command></term>
- <listitem>
- <para>
- Allow the default journal's filename to be overridden.
- The default is the zone's filename with "<filename>.jnl</filename>" appended.
- This is applicable to <command>master</command> and <command>slave</command> zones.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>max-journal-size</command></term>
- <listitem>
- <para>
- See the description of
- <command>max-journal-size</command> in <xref linkend="server_resource_limits"/>.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>max-transfer-time-in</command></term>
- <listitem>
- <para>
- See the description of
- <command>max-transfer-time-in</command> in <xref linkend="zone_transfers"/>.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>max-transfer-idle-in</command></term>
- <listitem>
- <para>
- See the description of
- <command>max-transfer-idle-in</command> in <xref linkend="zone_transfers"/>.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>max-transfer-time-out</command></term>
- <listitem>
- <para>
- See the description of
- <command>max-transfer-time-out</command> in <xref linkend="zone_transfers"/>.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>max-transfer-idle-out</command></term>
- <listitem>
- <para>
- See the description of
- <command>max-transfer-idle-out</command> in <xref linkend="zone_transfers"/>.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>notify</command></term>
- <listitem>
- <para>
- See the description of
- <command>notify</command> in <xref linkend="boolean_options"/>.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>notify-delay</command></term>
- <listitem>
- <para>
- See the description of
- <command>notify-delay</command> in <xref linkend="tuning"/>.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>notify-to-soa</command></term>
- <listitem>
- <para>
- See the description of
- <command>notify-to-soa</command> in
- <xref linkend="boolean_options"/>.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>pubkey</command></term>
- <listitem>
- <para>
- In <acronym>BIND</acronym> 8, this option was
- intended for specifying
- a public zone key for verification of signatures in DNSSEC
- signed
- zones when they are loaded from disk. <acronym>BIND</acronym> 9 does not verify signatures
- on load and ignores the option.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>zone-statistics</command></term>
- <listitem>
- <para>
- If <userinput>yes</userinput>, the server will keep
- statistical
- information for this zone, which can be dumped to the
- <command>statistics-file</command> defined in
- the server options.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>server-addresses</command></term>
- <listitem>
- <para>
- Only meaningful for static-stub zones.
- This is a list of IP addresses to which queries
- should be sent in recursive resolution for the
- zone.
- A non empty list for this option will internally
- configure the apex NS RR with associated glue A or
- AAAA RRs.
- </para>
- <para>
- For example, if "example.com" is configured as a
- static-stub zone with 192.0.2.1 and 2001:db8::1234
- in a <command>server-addresses</command> option,
- the following RRs will be internally configured.
- </para>
-<programlisting>example.com. NS example.com.
-example.com. A 192.0.2.1
-example.com. AAAA 2001:db8::1234</programlisting>
- <para>
- These records are internally used to resolve
- names under the static-stub zone.
- For instance, if the server receives a query for
- "www.example.com" with the RD bit on, the server
- will initiate recursive resolution and send
- queries to 192.0.2.1 and/or 2001:db8::1234.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>server-names</command></term>
- <listitem>
- <para>
- Only meaningful for static-stub zones.
- This is a list of domain names of nameservers that
- act as authoritative servers of the static-stub
- zone.
- These names will be resolved to IP addresses when
- <command>named</command> needs to send queries to
- these servers.
- To make this supplemental resolution successful,
- these names must not be a subdomain of the origin
- name of static-stub zone.
- That is, when "example.net" is the origin of a
- static-stub zone, "ns.example" and
- "master.example.com" can be specified in the
- <command>server-names</command> option, but
- "ns.example.net" cannot, and will be rejected by
- the configuration parser.
- </para>
- <para>
- A non empty list for this option will internally
- configure the apex NS RR with the specified names.
- For example, if "example.com" is configured as a
- static-stub zone with "ns1.example.net" and
- "ns2.example.net"
- in a <command>server-names</command> option,
- the following RRs will be internally configured.
- </para>
-<programlisting>example.com. NS ns1.example.net.
-example.com. NS ns2.example.net.
-</programlisting>
- <para>
- These records are internally used to resolve
- names under the static-stub zone.
- For instance, if the server receives a query for
- "www.example.com" with the RD bit on, the server
- initiate recursive resolution,
- resolve "ns1.example.net" and/or
- "ns2.example.net" to IP addresses, and then send
- queries to (one or more of) these addresses.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>sig-validity-interval</command></term>
- <listitem>
- <para>
- See the description of
- <command>sig-validity-interval</command> in <xref linkend="tuning"/>.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>sig-signing-nodes</command></term>
- <listitem>
- <para>
- See the description of
- <command>sig-signing-nodes</command> in <xref linkend="tuning"/>.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>sig-signing-signatures</command></term>
- <listitem>
- <para>
- See the description of
- <command>sig-signing-signatures</command> in <xref linkend="tuning"/>.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>sig-signing-type</command></term>
- <listitem>
- <para>
- See the description of
- <command>sig-signing-type</command> in <xref linkend="tuning"/>.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>transfer-source</command></term>
- <listitem>
- <para>
- See the description of
- <command>transfer-source</command> in <xref linkend="zone_transfers"/>.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>transfer-source-v6</command></term>
- <listitem>
- <para>
- See the description of
- <command>transfer-source-v6</command> in <xref linkend="zone_transfers"/>.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>alt-transfer-source</command></term>
- <listitem>
- <para>
- See the description of
- <command>alt-transfer-source</command> in <xref linkend="zone_transfers"/>.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>alt-transfer-source-v6</command></term>
- <listitem>
- <para>
- See the description of
- <command>alt-transfer-source-v6</command> in <xref linkend="zone_transfers"/>.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>use-alt-transfer-source</command></term>
- <listitem>
- <para>
- See the description of
- <command>use-alt-transfer-source</command> in <xref linkend="zone_transfers"/>.
- </para>
- </listitem>
- </varlistentry>
-
-
- <varlistentry>
- <term><command>notify-source</command></term>
- <listitem>
- <para>
- See the description of
- <command>notify-source</command> in <xref linkend="zone_transfers"/>.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>notify-source-v6</command></term>
- <listitem>
- <para>
- See the description of
- <command>notify-source-v6</command> in <xref linkend="zone_transfers"/>.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>min-refresh-time</command></term>
- <term><command>max-refresh-time</command></term>
- <term><command>min-retry-time</command></term>
- <term><command>max-retry-time</command></term>
- <listitem>
- <para>
- See the description in <xref linkend="tuning"/>.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>ixfr-from-differences</command></term>
- <listitem>
- <para>
- See the description of
- <command>ixfr-from-differences</command> in <xref linkend="boolean_options"/>.
- (Note that the <command>ixfr-from-differences</command>
- <userinput>master</userinput> and
- <userinput>slave</userinput> choices are not
- available at the zone level.)
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>key-directory</command></term>
- <listitem>
- <para>
- See the description of
- <command>key-directory</command> in <xref linkend="options"/>.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>auto-dnssec</command></term>
- <listitem>
- <para>
- Zones configured for dynamic DNS may also use this
- option to allow varying levels of automatic DNSSEC key
- management. There are three possible settings:
- </para>
- <para>
- <command>auto-dnssec allow;</command> permits
- keys to be updated and the zone fully re-signed
- whenever the user issues the command <command>rndc sign
- <replaceable>zonename</replaceable></command>.
- </para>
- <para>
- <command>auto-dnssec maintain;</command> includes the
- above, but also automatically adjusts the zone's DNSSEC
- keys on schedule, according to the keys' timing metadata
- (see <xref linkend="man.dnssec-keygen"/> and
- <xref linkend="man.dnssec-settime"/>). The command
- <command>rndc sign
- <replaceable>zonename</replaceable></command> causes
- <command>named</command> to load keys from the key
- repository and sign the zone with all keys that are
- active.
- <command>rndc loadkeys
- <replaceable>zonename</replaceable></command> causes
- <command>named</command> to load keys from the key
- repository and schedule key maintenance events to occur
- in the future, but it does not sign the full zone
- immediately. Note: once keys have been loaded for a
- zone the first time, the repository will be searched
- for changes periodically, regardless of whether
- <command>rndc loadkeys</command> is used. The recheck
- interval is defined by
- <command>dnssec-loadkeys-interval</command>.)
- </para>
- <para>
- The default setting is <command>auto-dnssec off</command>.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>serial-update-method</command></term>
- <listitem>
- <para>
- Zones configured for dynamic DNS may use this
- option to set the update method that will be used for
- the zone serial number in the SOA record.
- </para>
- <para>
- With the default setting of
- <command>serial-update-method increment;</command>, the
- SOA serial number will be incremented by one each time
- the zone is updated.
- </para>
- <para>
- When set to
- <command>serial-update-method unixtime;</command>, the
- SOA serial number will be set to the number of seconds
- since the UNIX epoch, unless the serial number is
- already greater than or equal to that value, in which
- case it is simply incremented by one.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>inline-signing</command></term>
- <listitem>
- <para>
- If <literal>yes</literal>, this enables
- "bump in the wire" signing of a zone, where a
- unsigned zone is transferred in or loaded from
- disk and a signed version of the zone is served,
- with possibly, a different serial number. This
- behaviour is disabled by default.
- </para>
- </listitem>
- </varlistentry>
+ </sect3>
- <varlistentry>
- <term><command>multi-master</command></term>
- <listitem>
- <para>
- See the description of <command>multi-master</command> in
- <xref linkend="boolean_options"/>.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>masterfile-format</command></term>
- <listitem>
- <para>
- See the description of <command>masterfile-format</command>
- in <xref linkend="tuning"/>.
- </para>
- </listitem>
- </varlistentry>
+ <sect3>
+ <title>Content Filtering</title>
+ <para>
+ <acronym>BIND</acronym> 9 provides the ability to filter
+ out DNS responses from external DNS servers containing
+ certain types of data in the answer section.
+ Specifically, it can reject address (A or AAAA) records if
+ the corresponding IPv4 or IPv6 addresses match the given
+ <varname>address_match_list</varname> of the
+ <command>deny-answer-addresses</command> option.
+ It can also reject CNAME or DNAME records if the "alias"
+ name (i.e., the CNAME alias or the substituted query name
+ due to DNAME) matches the
+ given <varname>namelist</varname> of the
+ <command>deny-answer-aliases</command> option, where
+ "match" means the alias name is a subdomain of one of
+ the <varname>name_list</varname> elements.
+ If the optional <varname>namelist</varname> is specified
+ with <command>except-from</command>, records whose query name
+ matches the list will be accepted regardless of the filter
+ setting.
+ Likewise, if the alias name is a subdomain of the
+ corresponding zone, the <command>deny-answer-aliases</command>
+ filter will not apply;
+ for example, even if "example.com" is specified for
+ <command>deny-answer-aliases</command>,
+ </para>
+<programlisting>www.example.com. CNAME xxx.example.com.</programlisting>
- <varlistentry>
- <term><command>dnssec-secure-to-insecure</command></term>
- <listitem>
- <para>
- See the description of
- <command>dnssec-secure-to-insecure</command> in <xref linkend="boolean_options"/>.
- </para>
- </listitem>
- </varlistentry>
-
- </variablelist>
-
- </sect3>
- <sect3 id="dynamic_update_policies">
- <title>Dynamic Update Policies</title>
- <para><acronym>BIND</acronym> 9 supports two alternative
- methods of granting clients the right to perform
- dynamic updates to a zone, configured by the
- <command>allow-update</command> and
- <command>update-policy</command> option, respectively.
- </para>
- <para>
- The <command>allow-update</command> clause works the
- same way as in previous versions of <acronym>BIND</acronym>.
- It grants given clients the permission to update any
- record of any name in the zone.
- </para>
- <para>
- The <command>update-policy</command> clause
- allows more fine-grained control over what updates are
- allowed. A set of rules is specified, where each rule
- either grants or denies permissions for one or more
- names to be updated by one or more identities. If
- the dynamic update request message is signed (that is,
- it includes either a TSIG or SIG(0) record), the
- identity of the signer can be determined.
- </para>
- <para>
- Rules are specified in the <command>update-policy</command>
- zone option, and are only meaningful for master zones.
- When the <command>update-policy</command> statement
- is present, it is a configuration error for the
- <command>allow-update</command> statement to be
- present. The <command>update-policy</command> statement
- only examines the signer of a message; the source
- address is not relevant.
- </para>
- <para>
- There is a pre-defined <command>update-policy</command>
- rule which can be switched on with the command
- <command>update-policy local;</command>.
- Switching on this rule in a zone causes
- <command>named</command> to generate a TSIG session
- key and place it in a file, and to allow that key
- to update the zone. (By default, the file is
- <filename>/var/run/named/session.key</filename>, the key
- name is "local-ddns" and the key algorithm is HMAC-SHA256,
- but these values are configurable with the
- <command>session-keyfile</command>,
- <command>session-keyname</command> and
- <command>session-keyalg</command> options, respectively).
- </para>
- <para>
- A client running on the local system, and with appropriate
- permissions, may read that file and use the key to sign update
- requests. The zone's update policy will be set to allow that
- key to change any record within the zone. Assuming the
- key name is "local-ddns", this policy is equivalent to:
- </para>
+ <para>
+ returned by an "example.com" server will be accepted.
+ </para>
- <programlisting>update-policy { grant local-ddns zonesub any; };
- </programlisting>
+ <para>
+ In the <varname>address_match_list</varname> of the
+ <command>deny-answer-addresses</command> option, only
+ <varname>ip_addr</varname>
+ and <varname>ip_prefix</varname>
+ are meaningful;
+ any <varname>key_id</varname> will be silently ignored.
+ </para>
- <para>
- The command <command>nsupdate -l</command> sends update
- requests to localhost, and signs them using the session key.
- </para>
+ <para>
+ If a response message is rejected due to the filtering,
+ the entire message is discarded without being cached, and
+ a SERVFAIL error will be returned to the client.
+ </para>
- <para>
- Other rule definitions look like this:
- </para>
+ <para>
+ This filtering is intended to prevent "DNS rebinding attacks," in
+ which an attacker, in response to a query for a domain name the
+ attacker controls, returns an IP address within your own network or
+ an alias name within your own domain.
+ A naive web browser or script could then serve as an
+ unintended proxy, allowing the attacker
+ to get access to an internal node of your local network
+ that couldn't be externally accessed otherwise.
+ See the paper available at
+ <ulink url="http://portal.acm.org/citation.cfm?id=1315245.1315298">
+ http://portal.acm.org/citation.cfm?id=1315245.1315298
+ </ulink>
+ for more details about the attacks.
+ </para>
-<programlisting>
-( <command>grant</command> | <command>deny</command> ) <replaceable>identity</replaceable> <replaceable>nametype</replaceable> <optional> <replaceable>name</replaceable> </optional> <optional> <replaceable>types</replaceable> </optional>
+ <para>
+ For example, if you own a domain named "example.net" and
+ your internal network uses an IPv4 prefix 192.0.2.0/24,
+ you might specify the following rules:
+ </para>
+
+<programlisting>deny-answer-addresses { 192.0.2.0/24; } except-from { "example.net"; };
+deny-answer-aliases { "example.net"; };
</programlisting>
- <para>
- Each rule grants or denies privileges. Once a message has
- successfully matched a rule, the operation is immediately
- granted or denied and no further rules are examined. A rule
- is matched when the signer matches the identity field, the
- name matches the name field in accordance with the nametype
- field, and the type matches the types specified in the type
- field.
- </para>
- <para>
- No signer is required for <replaceable>tcp-self</replaceable>
- or <replaceable>6to4-self</replaceable> however the standard
- reverse mapping / prefix conversion must match the identity
- field.
- </para>
- <para>
- The identity field specifies a name or a wildcard
- name. Normally, this is the name of the TSIG or
- SIG(0) key used to sign the update request. When a
- TKEY exchange has been used to create a shared secret,
- the identity of the shared secret is the same as the
- identity of the key used to authenticate the TKEY
- exchange. TKEY is also the negotiation method used
- by GSS-TSIG, which establishes an identity that is
- the Kerberos principal of the client, such as
- <userinput>"user@host.domain"</userinput>. When the
- <replaceable>identity</replaceable> field specifies
- a wildcard name, it is subject to DNS wildcard
- expansion, so the rule will apply to multiple identities.
- The <replaceable>identity</replaceable> field must
- contain a fully-qualified domain name.
- </para>
- <para>
- For nametypes <varname>krb5-self</varname>,
- <varname>ms-self</varname>, <varname>krb5-subdomain</varname>,
- and <varname>ms-subdomain</varname> the
- <replaceable>identity</replaceable> field specifies
- the Windows or Kerberos realm of the machine belongs to.
- </para>
- <para>
- The <replaceable>nametype</replaceable> field has 13
- values:
- <varname>name</varname>, <varname>subdomain</varname>,
- <varname>wildcard</varname>, <varname>self</varname>,
- <varname>selfsub</varname>, <varname>selfwild</varname>,
- <varname>krb5-self</varname>, <varname>ms-self</varname>,
- <varname>krb5-subdomain</varname>,
- <varname>ms-subdomain</varname>,
- <varname>tcp-self</varname>, <varname>6to4-self</varname>,
- <varname>zonesub</varname>, and <varname>external</varname>.
- </para>
- <informaltable>
- <tgroup cols="2" colsep="0" rowsep="0" tgroupstyle="4Level-table">
- <colspec colname="1" colnum="1" colsep="0" colwidth="0.819in"/>
- <colspec colname="2" colnum="2" colsep="0" colwidth="3.681in"/>
- <tbody>
- <row rowsep="0">
- <entry colname="1">
- <para>
- <varname>name</varname>
- </para>
- </entry> <entry colname="2">
- <para>
- Exact-match semantics. This rule matches
- when the name being updated is identical
- to the contents of the
- <replaceable>name</replaceable> field.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para>
- <varname>subdomain</varname>
- </para>
- </entry> <entry colname="2">
- <para>
- This rule matches when the name being updated
- is a subdomain of, or identical to, the
- contents of the <replaceable>name</replaceable>
- field.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para>
- <varname>zonesub</varname>
- </para>
- </entry> <entry colname="2">
- <para>
- This rule is similar to subdomain, except that
- it matches when the name being updated is a
- subdomain of the zone in which the
- <command>update-policy</command> statement
- appears. This obviates the need to type the zone
- name twice, and enables the use of a standard
- <command>update-policy</command> statement in
- multiple zones without modification.
- </para>
- <para>
- When this rule is used, the
- <replaceable>name</replaceable> field is omitted.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para>
- <varname>wildcard</varname>
- </para>
- </entry> <entry colname="2">
- <para>
- The <replaceable>name</replaceable> field
- is subject to DNS wildcard expansion, and
- this rule matches when the name being updated
- name is a valid expansion of the wildcard.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para>
- <varname>self</varname>
- </para>
- </entry>
- <entry colname="2">
- <para>
- This rule matches when the name being updated
- matches the contents of the
- <replaceable>identity</replaceable> field.
- The <replaceable>name</replaceable> field
- is ignored, but should be the same as the
- <replaceable>identity</replaceable> field.
- The <varname>self</varname> nametype is
- most useful when allowing using one key per
- name to update, where the key has the same
- name as the name to be updated. The
- <replaceable>identity</replaceable> would
- be specified as <constant>*</constant> (an asterisk) in
- this case.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para>
- <varname>selfsub</varname>
- </para>
- </entry> <entry colname="2">
- <para>
- This rule is similar to <varname>self</varname>
- except that subdomains of <varname>self</varname>
- can also be updated.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para>
- <varname>selfwild</varname>
- </para>
- </entry> <entry colname="2">
- <para>
- This rule is similar to <varname>self</varname>
- except that only subdomains of
- <varname>self</varname> can be updated.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para>
- <varname>ms-self</varname>
- </para>
- </entry> <entry colname="2">
- <para>
- This rule takes a Windows machine principal
- (machine$@REALM) for machine in REALM and
- and converts it machine.realm allowing the machine
- to update machine.realm. The REALM to be matched
- is specified in the <replaceable>identity</replaceable>
- field.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para>
- <varname>ms-subdomain</varname>
- </para>
- </entry> <entry colname="2">
- <para>
- This rule takes a Windows machine principal
- (machine$@REALM) for machine in REALM and
- converts it to machine.realm allowing the machine
- to update subdomains of machine.realm. The REALM
- to be matched is specified in the
- <replaceable>identity</replaceable> field.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para>
- <varname>krb5-self</varname>
- </para>
- </entry> <entry colname="2">
- <para>
- This rule takes a Kerberos machine principal
- (host/machine@REALM) for machine in REALM and
- and converts it machine.realm allowing the machine
- to update machine.realm. The REALM to be matched
- is specified in the <replaceable>identity</replaceable>
- field.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para>
- <varname>krb5-subdomain</varname>
- </para>
- </entry> <entry colname="2">
- <para>
- This rule takes a Kerberos machine principal
- (host/machine@REALM) for machine in REALM and
- converts it to machine.realm allowing the machine
- to update subdomains of machine.realm. The REALM
- to be matched is specified in the
- <replaceable>identity</replaceable> field.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para>
- <varname>tcp-self</varname>
- </para>
- </entry> <entry colname="2">
- <para>
- Allow updates that have been sent via TCP and
- for which the standard mapping from the initiating
- IP address into the IN-ADDR.ARPA and IP6.ARPA
- namespaces match the name to be updated.
- </para>
- <note>
- It is theoretically possible to spoof these TCP
- sessions.
- </note>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para>
- <varname>6to4-self</varname>
- </para>
- </entry> <entry colname="2">
- <para>
- Allow the 6to4 prefix to be update by any TCP
- connection from the 6to4 network or from the
- corresponding IPv4 address. This is intended
- to allow NS or DNAME RRsets to be added to the
- reverse tree.
- </para>
- <note>
- It is theoretically possible to spoof these TCP
- sessions.
- </note>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para>
- <varname>external</varname>
- </para>
- </entry> <entry colname="2">
- <para>
- This rule allows <command>named</command>
- to defer the decision of whether to allow a
- given update to an external daemon.
- </para>
- <para>
- The method of communicating with the daemon is
- specified in the <replaceable>identity</replaceable>
- field, the format of which is
- "<constant>local:</constant><replaceable>path</replaceable>",
- where <replaceable>path</replaceable> is the location
- of a UNIX-domain socket. (Currently, "local" is the
- only supported mechanism.)
- </para>
- <para>
- Requests to the external daemon are sent over the
- UNIX-domain socket as datagrams with the following
- format:
- </para>
- <programlisting>
- Protocol version number (4 bytes, network byte order, currently 1)
- Request length (4 bytes, network byte order)
- Signer (null-terminated string)
- Name (null-terminated string)
- TCP source address (null-terminated string)
- Rdata type (null-terminated string)
- Key (null-terminated string)
- TKEY token length (4 bytes, network byte order)
- TKEY token (remainder of packet)</programlisting>
- <para>
- The daemon replies with a four-byte value in
- network byte order, containing either 0 or 1; 0
- indicates that the specified update is not
- permitted, and 1 indicates that it is.
- </para>
- </entry>
- </row>
- </tbody>
- </tgroup>
- </informaltable>
-
- <para>
- In all cases, the <replaceable>name</replaceable>
- field must specify a fully-qualified domain name.
- </para>
-
- <para>
- If no types are explicitly specified, this rule matches
- all types except RRSIG, NS, SOA, NSEC and NSEC3. Types
- may be specified by name, including "ANY" (ANY matches
- all types except NSEC and NSEC3, which can never be
- updated). Note that when an attempt is made to delete
- all records associated with a name, the rules are
- checked for each existing record type.
- </para>
- </sect3>
-
- <sect3>
- <title>Multiple views</title>
- <para>
- When multiple views are in use, a zone may be
- referenced by more than one of them. Often, the views
- will contain different zones with the same name, allowing
- different clients to receive different answers for the same
- queries. At times, however, it is desirable for multiple
- views to contain identical zones. The
- <command>in-view</command> zone option provides an efficient
- way to do this: it allows a view to reference a zone that
- was defined in a previously configured view. Example:
- </para>
- <programlisting>
-view internal {
- match-clients { 10/8; };
-
- zone example.com {
- type master;
- file "example-external.db";
- };
-};
+ <para>
+ If an external attacker lets a web browser in your local
+ network look up an IPv4 address of "attacker.example.com",
+ the attacker's DNS server would return a response like this:
+ </para>
-view external {
- match-clients { any; };
+<programlisting>attacker.example.com. A 192.0.2.1</programlisting>
- zone example.com {
- in-view internal;
- };
-};
- </programlisting>
- <para>
- An <command>in-view</command> option cannot refer to a view
- that is configured later in the configuration file.
- </para>
- <para>
- A <command>zone</command> statement which uses the
- <command>in-view</command> option may not use any other
- options with the exception of <command>forward</command>
- and <command>forwarders</command>. (These options control
- the behavior of the containing view, rather than changing
- the zone object itself.)
- </para>
- </sect3>
-
- </sect2>
- </sect1>
- <sect1>
- <title>Zone File</title>
- <sect2 id="types_of_resource_records_and_when_to_use_them">
- <title>Types of Resource Records and When to Use Them</title>
- <para>
- This section, largely borrowed from RFC 1034, describes the
- concept of a Resource Record (RR) and explains when each is used.
- Since the publication of RFC 1034, several new RRs have been
- identified
- and implemented in the DNS. These are also included.
- </para>
- <sect3>
- <title>Resource Records</title>
-
- <para>
- A domain name identifies a node. Each node has a set of
- resource information, which may be empty. The set of resource
- information associated with a particular name is composed of
- separate RRs. The order of RRs in a set is not significant and
- need not be preserved by name servers, resolvers, or other
- parts of the DNS. However, sorting of multiple RRs is
- permitted for optimization purposes, for example, to specify
- that a particular nearby server be tried first. See <xref linkend="the_sortlist_statement"/> and <xref linkend="rrset_ordering"/>.
- </para>
-
- <para>
- The components of a Resource Record are:
- </para>
- <informaltable colsep="0" rowsep="0">
- <tgroup cols="2" colsep="0" rowsep="0" tgroupstyle="4Level-table">
- <colspec colname="1" colnum="1" colsep="0" colwidth="1.000in"/>
- <colspec colname="2" colnum="2" colsep="0" colwidth="3.500in"/>
- <tbody>
- <row rowsep="0">
- <entry colname="1">
- <para>
- owner name
- </para>
- </entry>
- <entry colname="2">
- <para>
- The domain name where the RR is found.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para>
- type
- </para>
- </entry>
- <entry colname="2">
- <para>
- An encoded 16-bit value that specifies
- the type of the resource record.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para>
- TTL
- </para>
- </entry>
- <entry colname="2">
- <para>
- The time-to-live of the RR. This field
- is a 32-bit integer in units of seconds, and is
- primarily used by
- resolvers when they cache RRs. The TTL describes how
- long a RR can
- be cached before it should be discarded.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para>
- class
- </para>
- </entry>
- <entry colname="2">
- <para>
- An encoded 16-bit value that identifies
- a protocol family or instance of a protocol.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para>
- RDATA
- </para>
- </entry>
- <entry colname="2">
- <para>
- The resource data. The format of the
- data is type (and sometimes class) specific.
- </para>
- </entry>
- </row>
- </tbody>
- </tgroup>
- </informaltable>
- <para>
- The following are <emphasis>types</emphasis> of valid RRs:
- </para>
- <informaltable colsep="0" rowsep="0">
- <tgroup cols="2" colsep="0" rowsep="0" tgroupstyle="4Level-table">
- <colspec colname="1" colnum="1" colsep="0" colwidth="0.875in"/>
- <colspec colname="2" colnum="2" colsep="0" colwidth="3.625in"/>
- <tbody>
- <row rowsep="0">
- <entry colname="1">
- <para>
- A
- </para>
- </entry>
- <entry colname="2">
- <para>
- A host address. In the IN class, this is a
- 32-bit IP address. Described in RFC 1035.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para>
- AAAA
- </para>
- </entry>
- <entry colname="2">
- <para>
- IPv6 address. Described in RFC 1886.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para>
- A6
- </para>
- </entry>
- <entry colname="2">
- <para>
- IPv6 address. This can be a partial
- address (a suffix) and an indirection to the name
- where the rest of the
- address (the prefix) can be found. Experimental.
- Described in RFC 2874.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para>
- AFSDB
- </para>
- </entry>
- <entry colname="2">
- <para>
- Location of AFS database servers.
- Experimental. Described in RFC 1183.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para>
- APL
- </para>
- </entry>
- <entry colname="2">
- <para>
- Address prefix list. Experimental.
- Described in RFC 3123.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para>
- CERT
- </para>
- </entry>
- <entry colname="2">
- <para>
- Holds a digital certificate.
- Described in RFC 2538.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para>
- CNAME
- </para>
- </entry>
- <entry colname="2">
- <para>
- Identifies the canonical name of an alias.
- Described in RFC 1035.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para>
- DHCID
- </para>
- </entry>
- <entry colname="2">
- <para>
- Is used for identifying which DHCP client is
- associated with this name. Described in RFC 4701.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para>
- DNAME
- </para>
- </entry>
- <entry colname="2">
- <para>
- Replaces the domain name specified with
- another name to be looked up, effectively aliasing an
- entire
- subtree of the domain name space rather than a single
- record
- as in the case of the CNAME RR.
- Described in RFC 2672.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para>
- DNSKEY
- </para>
- </entry>
- <entry colname="2">
- <para>
- Stores a public key associated with a signed
- DNS zone. Described in RFC 4034.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para>
- DS
- </para>
- </entry>
- <entry colname="2">
- <para>
- Stores the hash of a public key associated with a
- signed DNS zone. Described in RFC 4034.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para>
- GPOS
- </para>
- </entry>
- <entry colname="2">
- <para>
- Specifies the global position. Superseded by LOC.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para>
- HINFO
- </para>
- </entry>
- <entry colname="2">
- <para>
- Identifies the CPU and OS used by a host.
- Described in RFC 1035.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para>
- IPSECKEY
- </para>
- </entry>
- <entry colname="2">
- <para>
- Provides a method for storing IPsec keying material in
- DNS. Described in RFC 4025.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para>
- ISDN
- </para>
- </entry>
- <entry colname="2">
- <para>
- Representation of ISDN addresses.
- Experimental. Described in RFC 1183.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para>
- KEY
- </para>
- </entry>
- <entry colname="2">
- <para>
- Stores a public key associated with a
- DNS name. Used in original DNSSEC; replaced
- by DNSKEY in DNSSECbis, but still used with
- SIG(0). Described in RFCs 2535 and 2931.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para>
- KX
- </para>
- </entry>
- <entry colname="2">
- <para>
- Identifies a key exchanger for this
- DNS name. Described in RFC 2230.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para>
- LOC
- </para>
- </entry>
- <entry colname="2">
- <para>
- For storing GPS info. Described in RFC 1876.
- Experimental.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para>
- MX
- </para>
- </entry>
- <entry colname="2">
- <para>
- Identifies a mail exchange for the domain with
- a 16-bit preference value (lower is better)
- followed by the host name of the mail exchange.
- Described in RFC 974, RFC 1035.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para>
- NAPTR
- </para>
- </entry>
- <entry colname="2">
- <para>
- Name authority pointer. Described in RFC 2915.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para>
- NSAP
- </para>
- </entry>
- <entry colname="2">
- <para>
- A network service access point.
- Described in RFC 1706.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para>
- NS
- </para>
- </entry>
- <entry colname="2">
- <para>
- The authoritative name server for the
- domain. Described in RFC 1035.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para>
- NSEC
- </para>
- </entry>
- <entry colname="2">
- <para>
- Used in DNSSECbis to securely indicate that
- RRs with an owner name in a certain name interval do
- not exist in
- a zone and indicate what RR types are present for an
- existing name.
- Described in RFC 4034.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para>
- NSEC3
- </para>
- </entry>
- <entry colname="2">
- <para>
- Used in DNSSECbis to securely indicate that
- RRs with an owner name in a certain name
- interval do not exist in a zone and indicate
- what RR types are present for an existing
- name. NSEC3 differs from NSEC in that it
- prevents zone enumeration but is more
- computationally expensive on both the server
- and the client than NSEC. Described in RFC
- 5155.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para>
- NSEC3PARAM
- </para>
- </entry>
- <entry colname="2">
- <para>
- Used in DNSSECbis to tell the authoritative
- server which NSEC3 chains are available to use.
- Described in RFC 5155.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para>
- NXT
- </para>
- </entry>
- <entry colname="2">
- <para>
- Used in DNSSEC to securely indicate that
- RRs with an owner name in a certain name interval do
- not exist in
- a zone and indicate what RR types are present for an
- existing name.
- Used in original DNSSEC; replaced by NSEC in
- DNSSECbis.
- Described in RFC 2535.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para>
- PTR
- </para>
- </entry>
- <entry colname="2">
- <para>
- A pointer to another part of the domain
- name space. Described in RFC 1035.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para>
- PX
- </para>
- </entry>
- <entry colname="2">
- <para>
- Provides mappings between RFC 822 and X.400
- addresses. Described in RFC 2163.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para>
- RP
- </para>
- </entry>
- <entry colname="2">
- <para>
- Information on persons responsible
- for the domain. Experimental. Described in RFC 1183.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para>
- RRSIG
- </para>
- </entry>
- <entry colname="2">
- <para>
- Contains DNSSECbis signature data. Described
- in RFC 4034.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para>
- RT
- </para>
- </entry>
- <entry colname="2">
- <para>
- Route-through binding for hosts that
- do not have their own direct wide area network
- addresses.
- Experimental. Described in RFC 1183.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para>
- SIG
- </para>
- </entry>
- <entry colname="2">
- <para>
- Contains DNSSEC signature data. Used in
- original DNSSEC; replaced by RRSIG in
- DNSSECbis, but still used for SIG(0).
- Described in RFCs 2535 and 2931.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para>
- SOA
- </para>
- </entry>
- <entry colname="2">
- <para>
- Identifies the start of a zone of authority.
- Described in RFC 1035.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para>
- SPF
- </para>
- </entry>
- <entry colname="2">
- <para>
- Contains the Sender Policy Framework information
- for a given email domain. Described in RFC 4408.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para>
- SRV
- </para>
- </entry>
- <entry colname="2">
- <para>
- Information about well known network
- services (replaces WKS). Described in RFC 2782.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para>
- SSHFP
- </para>
- </entry>
- <entry colname="2">
- <para>
- Provides a way to securely publish a secure shell key's
- fingerprint. Described in RFC 4255.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para>
- TXT
- </para>
- </entry>
- <entry colname="2">
- <para>
- Text records. Described in RFC 1035.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para>
- WKS
- </para>
- </entry>
- <entry colname="2">
- <para>
- Information about which well known
- network services, such as SMTP, that a domain
- supports. Historical.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para>
- X25
- </para>
- </entry>
- <entry colname="2">
- <para>
- Representation of X.25 network addresses.
- Experimental. Described in RFC 1183.
- </para>
- </entry>
- </row>
- </tbody>
- </tgroup>
- </informaltable>
- <para>
- The following <emphasis>classes</emphasis> of resource records
- are currently valid in the DNS:
- </para>
- <informaltable colsep="0" rowsep="0"><tgroup cols="2" colsep="0" rowsep="0" tgroupstyle="4Level-table">
- <colspec colname="1" colnum="1" colsep="0" colwidth="0.875in"/>
- <colspec colname="2" colnum="2" colsep="0" colwidth="3.625in"/>
- <tbody>
-
- <row rowsep="0">
- <entry colname="1">
- <para>
- IN
- </para>
- </entry>
- <entry colname="2">
- <para>
- The Internet.
- </para>
- </entry>
- </row>
-
- <row rowsep="0">
- <entry colname="1">
- <para>
- CH
- </para>
- </entry>
- <entry colname="2">
- <para>
- Chaosnet, a LAN protocol created at MIT in the
- mid-1970s.
- Rarely used for its historical purpose, but reused for
- BIND's
- built-in server information zones, e.g.,
- <literal>version.bind</literal>.
- </para>
- </entry>
- </row>
-
- <row rowsep="0">
- <entry colname="1">
- <para>
- HS
- </para>
- </entry>
- <entry colname="2">
- <para>
- Hesiod, an information service
- developed by MIT's Project Athena. It is used to share
- information
- about various systems databases, such as users,
- groups, printers
- and so on.
- </para>
- </entry>
- </row>
-
- </tbody>
- </tgroup>
- </informaltable>
-
- <para>
- The owner name is often implicit, rather than forming an
- integral
- part of the RR. For example, many name servers internally form
- tree
- or hash structures for the name space, and chain RRs off nodes.
- The remaining RR parts are the fixed header (type, class, TTL)
- which is consistent for all RRs, and a variable part (RDATA)
- that
- fits the needs of the resource being described.
- </para>
- <para>
- The meaning of the TTL field is a time limit on how long an
- RR can be kept in a cache. This limit does not apply to
- authoritative
- data in zones; it is also timed out, but by the refreshing
- policies
- for the zone. The TTL is assigned by the administrator for the
- zone where the data originates. While short TTLs can be used to
- minimize caching, and a zero TTL prohibits caching, the
- realities
- of Internet performance suggest that these times should be on
- the
- order of days for the typical host. If a change can be
- anticipated,
- the TTL can be reduced prior to the change to minimize
- inconsistency
- during the change, and then increased back to its former value
- following
- the change.
- </para>
- <para>
- The data in the RDATA section of RRs is carried as a combination
- of binary strings and domain names. The domain names are
- frequently
- used as "pointers" to other data in the DNS.
- </para>
- </sect3>
- <sect3>
- <title>Textual expression of RRs</title>
- <para>
- RRs are represented in binary form in the packets of the DNS
- protocol, and are usually represented in highly encoded form
- when
- stored in a name server or resolver. In the examples provided
- in
- RFC 1034, a style similar to that used in master files was
- employed
- in order to show the contents of RRs. In this format, most RRs
- are shown on a single line, although continuation lines are
- possible
- using parentheses.
- </para>
- <para>
- The start of the line gives the owner of the RR. If a line
- begins with a blank, then the owner is assumed to be the same as
- that of the previous RR. Blank lines are often included for
- readability.
- </para>
- <para>
- Following the owner, we list the TTL, type, and class of the
- RR. Class and type use the mnemonics defined above, and TTL is
- an integer before the type field. In order to avoid ambiguity
- in
- parsing, type and class mnemonics are disjoint, TTLs are
- integers,
- and the type mnemonic is always last. The IN class and TTL
- values
- are often omitted from examples in the interests of clarity.
- </para>
- <para>
- The resource data or RDATA section of the RR are given using
- knowledge of the typical representation for the data.
- </para>
- <para>
- For example, we might show the RRs carried in a message as:
- </para>
- <informaltable colsep="0" rowsep="0"><tgroup cols="3" colsep="0" rowsep="0" tgroupstyle="4Level-table">
- <colspec colname="1" colnum="1" colsep="0" colwidth="1.381in"/>
- <colspec colname="2" colnum="2" colsep="0" colwidth="1.020in"/>
- <colspec colname="3" colnum="3" colsep="0" colwidth="2.099in"/>
- <tbody>
- <row rowsep="0">
- <entry colname="1">
- <para>
- <literal>ISI.EDU.</literal>
- </para>
- </entry>
- <entry colname="2">
- <para>
- <literal>MX</literal>
- </para>
- </entry>
- <entry colname="3">
- <para>
- <literal>10 VENERA.ISI.EDU.</literal>
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para/>
- </entry>
- <entry colname="2">
- <para>
- <literal>MX</literal>
- </para>
- </entry>
- <entry colname="3">
- <para>
- <literal>10 VAXA.ISI.EDU</literal>
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para>
- <literal>VENERA.ISI.EDU</literal>
- </para>
- </entry>
- <entry colname="2">
- <para>
- <literal>A</literal>
- </para>
- </entry>
- <entry colname="3">
- <para>
- <literal>128.9.0.32</literal>
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para/>
- </entry>
- <entry colname="2">
- <para>
- <literal>A</literal>
- </para>
- </entry>
- <entry colname="3">
- <para>
- <literal>10.1.0.52</literal>
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para>
- <literal>VAXA.ISI.EDU</literal>
- </para>
- </entry>
- <entry colname="2">
- <para>
- <literal>A</literal>
- </para>
- </entry>
- <entry colname="3">
- <para>
- <literal>10.2.0.27</literal>
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para/>
- </entry>
- <entry colname="2">
- <para>
- <literal>A</literal>
- </para>
- </entry>
- <entry colname="3">
- <para>
- <literal>128.9.0.33</literal>
- </para>
- </entry>
- </row>
- </tbody>
- </tgroup>
- </informaltable>
- <para>
- The MX RRs have an RDATA section which consists of a 16-bit
- number followed by a domain name. The address RRs use a
- standard
- IP address format to contain a 32-bit internet address.
- </para>
- <para>
- The above example shows six RRs, with two RRs at each of three
- domain names.
- </para>
- <para>
- Similarly we might see:
- </para>
- <informaltable colsep="0" rowsep="0"><tgroup cols="3" colsep="0" rowsep="0" tgroupstyle="4Level-table">
- <colspec colname="1" colnum="1" colsep="0" colwidth="1.491in"/>
- <colspec colname="2" colnum="2" colsep="0" colwidth="1.067in"/>
- <colspec colname="3" colnum="3" colsep="0" colwidth="2.067in"/>
- <tbody>
- <row rowsep="0">
- <entry colname="1">
- <para>
- <literal>XX.LCS.MIT.EDU.</literal>
- </para>
- </entry>
- <entry colname="2">
- <para>
- <literal>IN A</literal>
- </para>
- </entry>
- <entry colname="3">
- <para>
- <literal>10.0.0.44</literal>
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1"/>
- <entry colname="2">
- <para>
- <literal>CH A</literal>
- </para>
- </entry>
- <entry colname="3">
- <para>
- <literal>MIT.EDU. 2420</literal>
- </para>
- </entry>
- </row>
- </tbody>
- </tgroup>
- </informaltable>
- <para>
- This example shows two addresses for
- <literal>XX.LCS.MIT.EDU</literal>, each of a different class.
- </para>
- </sect3>
- </sect2>
-
- <sect2>
- <title>Discussion of MX Records</title>
-
- <para>
- As described above, domain servers store information as a
- series of resource records, each of which contains a particular
- piece of information about a given domain name (which is usually,
- but not always, a host). The simplest way to think of a RR is as
- a typed pair of data, a domain name matched with a relevant datum,
- and stored with some additional type information to help systems
- determine when the RR is relevant.
- </para>
-
- <para>
- MX records are used to control delivery of email. The data
- specified in the record is a priority and a domain name. The
- priority
- controls the order in which email delivery is attempted, with the
- lowest number first. If two priorities are the same, a server is
- chosen randomly. If no servers at a given priority are responding,
- the mail transport agent will fall back to the next largest
- priority.
- Priority numbers do not have any absolute meaning — they are
- relevant
- only respective to other MX records for that domain name. The
- domain
- name given is the machine to which the mail will be delivered.
- It <emphasis>must</emphasis> have an associated address record
- (A or AAAA) — CNAME is not sufficient.
- </para>
- <para>
- For a given domain, if there is both a CNAME record and an
- MX record, the MX record is in error, and will be ignored.
- Instead,
- the mail will be delivered to the server specified in the MX
- record
- pointed to by the CNAME.
- For example:
- </para>
- <informaltable colsep="0" rowsep="0">
- <tgroup cols="5" colsep="0" rowsep="0" tgroupstyle="3Level-table">
- <colspec colname="1" colnum="1" colsep="0" colwidth="1.708in"/>
- <colspec colname="2" colnum="2" colsep="0" colwidth="0.444in"/>
- <colspec colname="3" colnum="3" colsep="0" colwidth="0.444in"/>
- <colspec colname="4" colnum="4" colsep="0" colwidth="0.976in"/>
- <colspec colname="5" colnum="5" colsep="0" colwidth="1.553in"/>
- <tbody>
- <row rowsep="0">
- <entry colname="1">
- <para>
- <literal>example.com.</literal>
- </para>
- </entry>
- <entry colname="2">
- <para>
- <literal>IN</literal>
- </para>
- </entry>
- <entry colname="3">
- <para>
- <literal>MX</literal>
- </para>
- </entry>
- <entry colname="4">
- <para>
- <literal>10</literal>
- </para>
- </entry>
- <entry colname="5">
- <para>
- <literal>mail.example.com.</literal>
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para/>
- </entry>
- <entry colname="2">
- <para>
- <literal>IN</literal>
- </para>
- </entry>
- <entry colname="3">
- <para>
- <literal>MX</literal>
- </para>
- </entry>
- <entry colname="4">
- <para>
- <literal>10</literal>
- </para>
- </entry>
- <entry colname="5">
- <para>
- <literal>mail2.example.com.</literal>
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para/>
- </entry>
- <entry colname="2">
- <para>
- <literal>IN</literal>
- </para>
- </entry>
- <entry colname="3">
- <para>
- <literal>MX</literal>
- </para>
- </entry>
- <entry colname="4">
- <para>
- <literal>20</literal>
- </para>
- </entry>
- <entry colname="5">
- <para>
- <literal>mail.backup.org.</literal>
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para>
- <literal>mail.example.com.</literal>
- </para>
- </entry>
- <entry colname="2">
- <para>
- <literal>IN</literal>
- </para>
- </entry>
- <entry colname="3">
- <para>
- <literal>A</literal>
- </para>
- </entry>
- <entry colname="4">
- <para>
- <literal>10.0.0.1</literal>
- </para>
- </entry>
- <entry colname="5">
- <para/>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para>
- <literal>mail2.example.com.</literal>
- </para>
- </entry>
- <entry colname="2">
- <para>
- <literal>IN</literal>
- </para>
- </entry>
- <entry colname="3">
- <para>
- <literal>A</literal>
- </para>
- </entry>
- <entry colname="4">
- <para>
- <literal>10.0.0.2</literal>
- </para>
- </entry>
- <entry colname="5">
- <para/>
- </entry>
- </row>
- </tbody>
- </tgroup>
- </informaltable><para>
- Mail delivery will be attempted to <literal>mail.example.com</literal> and
- <literal>mail2.example.com</literal> (in
- any order), and if neither of those succeed, delivery to <literal>mail.backup.org</literal> will
- be attempted.
- </para>
- </sect2>
- <sect2 id="Setting_TTLs">
- <title>Setting TTLs</title>
- <para>
- The time-to-live of the RR field is a 32-bit integer represented
- in units of seconds, and is primarily used by resolvers when they
- cache RRs. The TTL describes how long a RR can be cached before it
- should be discarded. The following three types of TTL are
- currently
- used in a zone file.
- </para>
- <informaltable colsep="0" rowsep="0">
- <tgroup cols="2" colsep="0" rowsep="0" tgroupstyle="3Level-table">
- <colspec colname="1" colnum="1" colsep="0" colwidth="0.750in"/>
- <colspec colname="2" colnum="2" colsep="0" colwidth="4.375in"/>
- <tbody>
- <row rowsep="0">
- <entry colname="1">
- <para>
- SOA
- </para>
- </entry>
- <entry colname="2">
- <para>
- The last field in the SOA is the negative
- caching TTL. This controls how long other servers will
- cache no-such-domain
- (NXDOMAIN) responses from you.
- </para>
- <para>
- The maximum time for
- negative caching is 3 hours (3h).
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para>
- $TTL
- </para>
- </entry>
- <entry colname="2">
- <para>
- The $TTL directive at the top of the
- zone file (before the SOA) gives a default TTL for every
- RR without
- a specific TTL set.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para>
- RR TTLs
- </para>
- </entry>
- <entry colname="2">
- <para>
- Each RR can have a TTL as the second
- field in the RR, which will control how long other
- servers can cache
- the it.
- </para>
- </entry>
- </row>
- </tbody>
- </tgroup>
- </informaltable>
- <para>
- All of these TTLs default to units of seconds, though units
- can be explicitly specified, for example, <literal>1h30m</literal>.
- </para>
- </sect2>
- <sect2>
- <title>Inverse Mapping in IPv4</title>
- <para>
- Reverse name resolution (that is, translation from IP address
- to name) is achieved by means of the <emphasis>in-addr.arpa</emphasis> domain
- and PTR records. Entries in the in-addr.arpa domain are made in
- least-to-most significant order, read left to right. This is the
- opposite order to the way IP addresses are usually written. Thus,
- a machine with an IP address of 10.1.2.3 would have a
- corresponding
- in-addr.arpa name of
- 3.2.1.10.in-addr.arpa. This name should have a PTR resource record
- whose data field is the name of the machine or, optionally,
- multiple
- PTR records if the machine has more than one name. For example,
- in the <optional>example.com</optional> domain:
- </para>
- <informaltable colsep="0" rowsep="0">
- <tgroup cols="2" colsep="0" rowsep="0" tgroupstyle="3Level-table">
- <colspec colname="1" colnum="1" colsep="0" colwidth="1.125in"/>
- <colspec colname="2" colnum="2" colsep="0" colwidth="4.000in"/>
- <tbody>
- <row rowsep="0">
- <entry colname="1">
- <para>
- <literal>$ORIGIN</literal>
- </para>
- </entry>
- <entry colname="2">
- <para>
- <literal>2.1.10.in-addr.arpa</literal>
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para>
- <literal>3</literal>
- </para>
- </entry>
- <entry colname="2">
- <para>
- <literal>IN PTR foo.example.com.</literal>
- </para>
- </entry>
- </row>
- </tbody>
- </tgroup>
- </informaltable>
- <note>
- <para>
- The <command>$ORIGIN</command> lines in the examples
- are for providing context to the examples only — they do not
- necessarily
- appear in the actual usage. They are only used here to indicate
- that the example is relative to the listed origin.
- </para>
- </note>
- </sect2>
- <sect2>
- <title>Other Zone File Directives</title>
- <para>
- The Master File Format was initially defined in RFC 1035 and
- has subsequently been extended. While the Master File Format
- itself
- is class independent all records in a Master File must be of the
- same
- class.
- </para>
- <para>
- Master File Directives include <command>$ORIGIN</command>, <command>$INCLUDE</command>,
- and <command>$TTL.</command>
- </para>
- <sect3>
- <title>The <command>@</command> (at-sign)</title>
- <para>
- When used in the label (or name) field, the asperand or
- at-sign (@) symbol represents the current origin.
- At the start of the zone file, it is the
- <<varname>zone_name</varname>> (followed by
- trailing dot).
- </para>
- </sect3>
- <sect3>
- <title>The <command>$ORIGIN</command> Directive</title>
- <para>
- Syntax: <command>$ORIGIN</command>
- <replaceable>domain-name</replaceable>
- <optional><replaceable>comment</replaceable></optional>
- </para>
- <para><command>$ORIGIN</command>
- sets the domain name that will be appended to any
- unqualified records. When a zone is first read in there
- is an implicit <command>$ORIGIN</command>
- <<varname>zone_name</varname>><command>.</command>
- (followed by trailing dot).
- The current <command>$ORIGIN</command> is appended to
- the domain specified in the <command>$ORIGIN</command>
- argument if it is not absolute.
- </para>
+ <para>
+ in the answer section.
+ Since the rdata of this record (the IPv4 address) matches
+ the specified prefix 192.0.2.0/24, this response will be
+ ignored.
+ </para>
-<programlisting>
-$ORIGIN example.com.
-WWW CNAME MAIN-SERVER
-</programlisting>
+ <para>
+ On the other hand, if the browser looks up a legitimate
+ internal web server "www.example.net" and the
+ following response is returned to
+ the <acronym>BIND</acronym> 9 server
+ </para>
- <para>
- is equivalent to
- </para>
+<programlisting>www.example.net. A 192.0.2.2</programlisting>
-<programlisting>
-WWW.EXAMPLE.COM. CNAME MAIN-SERVER.EXAMPLE.COM.
-</programlisting>
+ <para>
+ it will be accepted since the owner name "www.example.net"
+ matches the <command>except-from</command> element,
+ "example.net".
+ </para>
- </sect3>
- <sect3>
- <title>The <command>$INCLUDE</command> Directive</title>
- <para>
- Syntax: <command>$INCLUDE</command>
- <replaceable>filename</replaceable>
- <optional>
-<replaceable>origin</replaceable> </optional>
- <optional> <replaceable>comment</replaceable> </optional>
- </para>
- <para>
- Read and process the file <filename>filename</filename> as
- if it were included into the file at this point. If <command>origin</command> is
- specified the file is processed with <command>$ORIGIN</command> set
- to that value, otherwise the current <command>$ORIGIN</command> is
- used.
- </para>
- <para>
- The origin and the current domain name
- revert to the values they had prior to the <command>$INCLUDE</command> once
- the file has been read.
- </para>
- <note>
- <para>
- RFC 1035 specifies that the current origin should be restored
- after
- an <command>$INCLUDE</command>, but it is silent
- on whether the current
- domain name should also be restored. BIND 9 restores both of
- them.
- This could be construed as a deviation from RFC 1035, a
- feature, or both.
- </para>
- </note>
- </sect3>
- <sect3>
- <title>The <command>$TTL</command> Directive</title>
- <para>
- Syntax: <command>$TTL</command>
- <replaceable>default-ttl</replaceable>
- <optional>
-<replaceable>comment</replaceable> </optional>
- </para>
- <para>
- Set the default Time To Live (TTL) for subsequent records
- with undefined TTLs. Valid TTLs are of the range 0-2147483647
- seconds.
- </para>
- <para><command>$TTL</command>
- is defined in RFC 2308.
- </para>
- </sect3>
- </sect2>
- <sect2>
- <title><acronym>BIND</acronym> Master File Extension: the <command>$GENERATE</command> Directive</title>
- <para>
- Syntax: <command>$GENERATE</command>
- <replaceable>range</replaceable>
- <replaceable>lhs</replaceable>
- <optional><replaceable>ttl</replaceable></optional>
- <optional><replaceable>class</replaceable></optional>
- <replaceable>type</replaceable>
- <replaceable>rhs</replaceable>
- <optional><replaceable>comment</replaceable></optional>
- </para>
- <para><command>$GENERATE</command>
- is used to create a series of resource records that only
- differ from each other by an
- iterator. <command>$GENERATE</command> can be used to
- easily generate the sets of records required to support
- sub /24 reverse delegations described in RFC 2317:
- Classless IN-ADDR.ARPA delegation.
- </para>
+ <para>
+ Note that this is not really an attack on the DNS per se.
+ In fact, there is nothing wrong for an "external" name to
+ be mapped to your "internal" IP address or domain name
+ from the DNS point of view.
+ It might actually be provided for a legitimate purpose,
+ such as for debugging.
+ As long as the mapping is provided by the correct owner,
+ it is not possible or does not make sense to detect
+ whether the intent of the mapping is legitimate or not
+ within the DNS.
+ The "rebinding" attack must primarily be protected at the
+ application that uses the DNS.
+ For a large site, however, it may be difficult to protect
+ all possible applications at once.
+ This filtering feature is provided only to help such an
+ operational environment;
+ it is generally discouraged to turn it on unless you are
+ very sure you have no other choice and the attack is a
+ real threat for your applications.
+ </para>
-<programlisting>$ORIGIN 0.0.192.IN-ADDR.ARPA.
-$GENERATE 1-2 @ NS SERVER$.EXAMPLE.
-$GENERATE 1-127 $ CNAME $.0</programlisting>
+ <para>
+ Care should be particularly taken if you want to use this
+ option for addresses within 127.0.0.0/8.
+ These addresses are obviously "internal", but many
+ applications conventionally rely on a DNS mapping from
+ some name to such an address.
+ Filtering out DNS records containing this address
+ spuriously can break such applications.
+ </para>
+ </sect3>
- <para>
- is equivalent to
- </para>
+ <sect3>
+ <title>Response Policy Zone (RPZ) Rewriting</title>
+ <para>
+ <acronym>BIND</acronym> 9 includes a limited
+ mechanism to modify DNS responses for requests
+ analogous to email anti-spam DNS blacklists.
+ Responses can be changed to deny the existence of domains(NXDOMAIN),
+ deny the existence of IP addresses for domains (NODATA),
+ or contain other IP addresses or data.
+ </para>
-<programlisting>0.0.0.192.IN-ADDR.ARPA. NS SERVER1.EXAMPLE.
-0.0.0.192.IN-ADDR.ARPA. NS SERVER2.EXAMPLE.
-1.0.0.192.IN-ADDR.ARPA. CNAME 1.0.0.0.192.IN-ADDR.ARPA.
-2.0.0.192.IN-ADDR.ARPA. CNAME 2.0.0.0.192.IN-ADDR.ARPA.
-...
-127.0.0.192.IN-ADDR.ARPA. CNAME 127.0.0.0.192.IN-ADDR.ARPA.
-</programlisting>
+ <para>
+ Response policy zones are named in the
+ <command>response-policy</command> option for the view or among the
+ global options if there is no response-policy option for the view.
+ Response policy zones are ordinary DNS zones containing RRsets
+ that can be queried normally if allowed.
+ It is usually best to restrict those queries with something like
+ <command>allow-query { localhost; };</command>.
+ </para>
- <para>
- Generate a set of A and MX records. Note the MX's right hand
- side is a quoted string. The quotes will be stripped when the
- right hand side is processed.
- </para>
-
-<programlisting>
-$ORIGIN EXAMPLE.
-$GENERATE 1-127 HOST-$ A 1.2.3.$
-$GENERATE 1-127 HOST-$ MX "0 ."</programlisting>
+ <para>
+ Five policy triggers can be encoded in RPZ records.
+ <variablelist>
+ <varlistentry>
+ <term><command>RPZ-CLIENT-IP</command></term>
+ <listitem>
+ <para>
+ IP records are triggered by the IP address of the
+ DNS client.
+ Client IP address triggers are encoded in records that have
+ owner names that are subdomains of
+ <command>rpz-client-ip</command> relativized to the
+ policy zone origin name
+ and encode an address or address block.
+ IPv4 addresses are represented as
+ <userinput>prefixlength.B4.B3.B2.B1.rpz-ip</userinput>.
+ The IPv4 prefix length must be between 1 and 32.
+ All four bytes, B4, B3, B2, and B1, must be present.
+ B4 is the decimal value of the least significant byte of the
+ IPv4 address as in IN-ADDR.ARPA.
+ </para>
- <para>
- is equivalent to
- </para>
+ <para>
+ IPv6 addresses are encoded in a format similar
+ to the standard IPv6 text representation,
+ <userinput>prefixlength.W8.W7.W6.W5.W4.W3.W2.W1.rpz-ip</userinput>.
+ Each of W8,...,W1 is a one to four digit hexadecimal number
+ representing 16 bits of the IPv6 address as in the standard
+ text representation of IPv6 addresses,
+ but reversed as in IN-ADDR.ARPA.
+ All 8 words must be present except when one set of consecutive
+ zero words is replaced with <userinput>.zz.</userinput>
+ analogous to double colons (::) in standard IPv6 text
+ encodings.
+ The IPv6 prefix length must be between 64 and 128.
+ </para>
+ </listitem>
+ </varlistentry>
-<programlisting>HOST-1.EXAMPLE. A 1.2.3.1
-HOST-1.EXAMPLE. MX 0 .
-HOST-2.EXAMPLE. A 1.2.3.2
-HOST-2.EXAMPLE. MX 0 .
-HOST-3.EXAMPLE. A 1.2.3.3
-HOST-3.EXAMPLE. MX 0 .
-...
-HOST-127.EXAMPLE. A 1.2.3.127
-HOST-127.EXAMPLE. MX 0 .
-</programlisting>
+ <varlistentry>
+ <term><command>QNAME</command></term>
+ <listitem>
+ <para>
+ QNAME policy records are triggered by query names of
+ requests and targets of CNAME records resolved to generate
+ the response.
+ The owner name of a QNAME policy record is
+ the query name relativized to the policy zone.
+ </para>
+ </listitem>
+ </varlistentry>
- <informaltable colsep="0" rowsep="0">
- <tgroup cols="2" colsep="0" rowsep="0" tgroupstyle="3Level-table">
- <colspec colname="1" colnum="1" colsep="0" colwidth="0.875in"/>
- <colspec colname="2" colnum="2" colsep="0" colwidth="4.250in"/>
- <tbody>
- <row rowsep="0">
- <entry colname="1">
- <para><command>range</command></para>
- </entry>
- <entry colname="2">
- <para>
- This can be one of two forms: start-stop
- or start-stop/step. If the first form is used, then step
- is set to
- 1. All of start, stop and step must be positive.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para><command>lhs</command></para>
- </entry>
- <entry colname="2">
- <para>This
- describes the owner name of the resource records
- to be created. Any single <command>$</command>
- (dollar sign)
- symbols within the <command>lhs</command> string
- are replaced by the iterator value.
-
- To get a $ in the output, you need to escape the
- <command>$</command> using a backslash
- <command>\</command>,
- e.g. <command>\$</command>. The
- <command>$</command> may optionally be followed
- by modifiers which change the offset from the
- iterator, field width and base.
-
- Modifiers are introduced by a
- <command>{</command> (left brace) immediately following the
- <command>$</command> as
- <command>${offset[,width[,base]]}</command>.
- For example, <command>${-20,3,d}</command>
- subtracts 20 from the current value, prints the
- result as a decimal in a zero-padded field of
- width 3.
+ <varlistentry>
+ <term><command>RPZ-IP</command></term>
+ <listitem>
+ <para>
+ IP triggers are IP addresses in an
+ A or AAAA record in the ANSWER section of a response.
+ They are encoded like client-IP triggers except as
+ subdomains of <command>rpz-ip</command>.
+ </para>
+ </listitem>
+ </varlistentry>
- Available output forms are decimal
- (<command>d</command>), octal
- (<command>o</command>), hexadecimal
- (<command>x</command> or <command>X</command>
- for uppercase) and nibble
- (<command>n</command> or <command>N</command>\
- for uppercase). The default modifier is
- <command>${0,0,d}</command>. If the
- <command>lhs</command> is not absolute, the
- current <command>$ORIGIN</command> is appended
- to the name.
- </para>
- <para>
- In nibble mode the value will be treated as
- if it was a reversed hexadecimal string
- with each hexadecimal digit as a separate
- label. The width field includes the label
- separator.
- </para>
- <para>
- For compatibility with earlier versions,
- <command>$$</command> is still recognized as
- indicating a literal $ in the output.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para><command>ttl</command></para>
- </entry>
- <entry colname="2">
- <para>
- Specifies the time-to-live of the generated records. If
- not specified this will be inherited using the
- normal TTL inheritance rules.
- </para>
- <para><command>class</command>
- and <command>ttl</command> can be
- entered in either order.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para><command>class</command></para>
- </entry>
- <entry colname="2">
- <para>
- Specifies the class of the generated records.
- This must match the zone class if it is
- specified.
- </para>
- <para><command>class</command>
- and <command>ttl</command> can be
- entered in either order.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para><command>type</command></para>
- </entry>
- <entry colname="2">
- <para>
- Any valid type.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para><command>rhs</command></para>
- </entry>
- <entry colname="2">
- <para>
- <command>rhs</command>, optionally, quoted string.
- </para>
- </entry>
- </row>
- </tbody>
- </tgroup>
- </informaltable>
- <para>
- The <command>$GENERATE</command> directive is a <acronym>BIND</acronym> extension
- and not part of the standard zone file format.
- </para>
- <para>
- BIND 8 does not support the optional TTL and CLASS fields.
- </para>
- </sect2>
+ <varlistentry>
+ <term><command>RPZ-NSDNAME</command></term>
+ <listitem>
+ <para>
+ NSDNAME triggers match names of authoritative servers
+ for the query name, a parent of the query name, a CNAME for
+ query name, or a parent of a CNAME.
+ They are encoded as subdomains of
+ <command>rpz-nsdname</command> relativized
+ to the RPZ origin name.
+ NSIP triggers match IP addresses in A and
+ AAAA RRsets for domains that can be checked against NSDNAME
+ policy records.
+ </para>
+ </listitem>
+ </varlistentry>
- <sect2 id="zonefile_format">
- <title>Additional File Formats</title>
- <para>
- In addition to the standard textual format, BIND 9
- supports the ability to read or dump to zone files in
- other formats.
- </para>
- <para>
- The <constant>raw</constant> format is
- a binary representation of zone data in a manner similar
- to that used in zone transfers. Since it does not require
- parsing text, load time is significantly reduced.
+ <varlistentry>
+ <term><command>RPZ-NSIP</command></term>
+ <listitem>
+ <para>
+ NSIP triggers are encoded like IP triggers except as
+ subdomains of <command>rpz-nsip</command>.
+ NSDNAME and NSIP triggers are checked only for names with at
+ least <command>min-ns-dots</command> dots.
+ The default value of <command>min-ns-dots</command> is 1 to
+ exclude top level domains.
+ </para>
+ </listitem>
+ </varlistentry>
+ </variablelist>
</para>
+
<para>
- An even faster alternative is the <constant>map</constant>
- format, which is an image of a <acronym>BIND</acronym> 9
- in-memory zone database; it is capable of being loaded
- directly into memory via the <command>mmap()</command>
- function; the zone can begin serving queries almost
- immediately.
+ The query response is checked against all response policy zones,
+ so two or more policy records can be triggered by a response.
+ Because DNS responses are rewritten according to at most one
+ policy record, a single record encoding an action (other than
+ <command>DISABLED</command> actions) must be chosen.
+ Triggers or the records that encode them are chosen for the
+ rewriting in the following order:
+ <itemizedlist>
+ <listitem>Choose the triggered record in the zone that appears
+ first in the <command>response-policy</command> option.
+ </listitem>
+ <listitem>Prefer CLIENT-IP to QNAME to IP to NSDNAME to NSIP
+ triggers in a single zone.
+ </listitem>
+ <listitem>Among NSDNAME triggers, prefer the
+ trigger that matches the smallest name under the DNSSEC ordering.
+ </listitem>
+ <listitem>Among IP or NSIP triggers, prefer the trigger
+ with the longest prefix.
+ </listitem>
+ <listitem>Among triggers with the same prefex length,
+ prefer the IP or NSIP trigger that matches
+ the smallest IP address.
+ </listitem>
+ </itemizedlist>
</para>
+
<para>
- For a primary server, a zone file in
- <constant>raw</constant> or <constant>map</constant>
- format is expected to be generated from a textual zone
- file by the <command>named-compilezone</command> command.
- For a secondary server or for a dynamic zone, it is automatically
- generated (if this format is specified by the
- <command>masterfile-format</command> option) when
- <command>named</command> dumps the zone contents after
- zone transfer or when applying prior updates.
+ When the processing of a response is restarted to resolve
+ DNAME or CNAME records and a policy record set has
+ not been triggered,
+ all response policy zones are again consulted for the
+ DNAME or CNAME names and addresses.
</para>
+
<para>
- If a zone file in a binary format needs manual modification,
- it first must be converted to a textual form by the
- <command>named-compilezone</command> command. All
- necessary modification should go to the text file, which
- should then be converted to the binary form by the
- <command>named-compilezone</command> command again.
- </para>
- <para>
- Note that <command>map</command> format is extremely
- architecture-specific. A <constant>map</constant>
- file <emphasis>cannot</emphasis> be used on a system
- with different pointer size, endianness or data alignment
- than the system on which it was generated, and should in
- general be used only inside a single system.
- While <constant>raw</constant> format uses
- network byte order and avoids architecture-dependent
- data alignment so that it is as portable as
- possible, it is also primarily expected to be used
- inside the same single system. To export a
- zone file in either <constant>raw</constant> or
- <constant>map</constant> format, or make a
- portable backup of such a file, conversion to
- <constant>text</constant> format is recommended.
- </para>
- </sect2>
- </sect1>
+ RPZ record sets are any types of DNS record except
+ DNAME or DNSSEC that encode actions or responses to
+ individual queries.
+ Any of the policies can be used with any of the triggers.
+ For example, while the <command>TCP-only</command> policy is
+ commonly used with <command>client-IP</command> triggers,
+ it cn be used with any type of trigger to force the use of
+ TCP for responses with owner names in a zone.
+ <variablelist>
+ <varlistentry>
+ <term><command>PASSTHRU</command></term>
+ <listitem>
+ <para>
+ The whitelist policy is specified
+ by a CNAME whose target is <command>rpz-passthru</command>.
+ It causes the response to not be rewritten
+ and is most often used to "poke holes" in policies for
+ CIDR blocks.
+ </para>
+ </listitem>
+ </varlistentry>
- <sect1 id="statistics">
- <title>BIND9 Statistics</title>
- <para>
- <acronym>BIND</acronym> 9 maintains lots of statistics
- information and provides several interfaces for users to
- get access to the statistics.
- The available statistics include all statistics counters
- that were available in <acronym>BIND</acronym> 8 and
- are meaningful in <acronym>BIND</acronym> 9,
- and other information that is considered useful.
- </para>
+ <varlistentry>
+ <term><command>DROP</command></term>
+ <listitem>
+ <para>
+ The blacklist policy is specified
+ by a CNAME whose target is <command>rpz-drop</command>.
+ It causes the response to be discarded.
+ Nothing is sent to the DNS client.
+ </para>
+ </listitem>
+ </varlistentry>
- <para>
- The statistics information is categorized into the following
- sections.
- </para>
+ <varlistentry>
+ <term><command>TCP-Only</command></term>
+ <listitem>
+ <para>
+ The "slip" policy is specified
+ by a CNAME whose target is <command>rpz-tcp-only</command>.
+ It changes UDP responses to short, truncated DNS responses
+ that require the DNS client to try again with TCP.
+ It is used to mitigate distributed DNS reflection attacks.
+ </para>
+ </listitem>
+ </varlistentry>
- <informaltable frame="all">
- <tgroup cols="2">
- <colspec colname="1" colnum="1" colsep="0" colwidth="3.300in"/>
- <colspec colname="2" colnum="2" colsep="0" colwidth="2.625in"/>
- <tbody>
+ <varlistentry>
+ <term><command>NXDOMAIN</command></term>
+ <listitem>
+ <para>
+ The domain undefined response is encoded
+ by a CNAME whose target is the root domain (.)
+ </para>
+ </listitem>
+ </varlistentry>
- <row rowsep="0">
- <entry colname="1">
- <para>Incoming Requests</para>
- </entry>
- <entry colname="2">
- <para>
- The number of incoming DNS requests for each OPCODE.
- </para>
- </entry>
- </row>
+ <varlistentry>
+ <term><command>NODATA</command></term>
+ <listitem>
+ <para>
+ The empty set of resource records is specified by
+ CNAME whose target is the wildcard top-level
+ domain (*.).
+ It rewrites the response to NODATA or ANCOUNT=1.
+ </para>
+ </listitem>
+ </varlistentry>
- <row rowsep="0">
- <entry colname="1">
- <para>Incoming Queries</para>
- </entry>
- <entry colname="2">
- <para>
- The number of incoming queries for each RR type.
- </para>
- </entry>
- </row>
+ <varlistentry>
+ <term><command>Local Data</command></term>
+ <listitem>
+ <para>
+ A set of ordinary DNS records can be used to answer queries.
+ Queries for record types not the set are answered with
+ NODATA.
+ </para>
- <row rowsep="0">
- <entry colname="1">
- <para>Outgoing Queries</para>
- </entry>
- <entry colname="2">
- <para>
- The number of outgoing queries for each RR
- type sent from the internal resolver.
- Maintained per view.
- </para>
- </entry>
- </row>
+ <para>
+ A special form of local data is a CNAME whose target is a
+ wildcard such as *.example.com.
+ It is used as if were an ordinary CNAME after the astrisk (*)
+ has been replaced with the query name.
+ The purpose for this special form is query logging in the
+ walled garden's authority DNS server.
+ </para>
+ </listitem>
+ </varlistentry>
+ </variablelist>
+ </para>
- <row rowsep="0">
- <entry colname="1">
- <para>Name Server Statistics</para>
- </entry>
- <entry colname="2">
- <para>
- Statistics counters about incoming request processing.
- </para>
- </entry>
- </row>
+ <para>
+ All of the actions specified in all of the individual records
+ in a policy zone
+ can be overridden with a <command>policy</command> clause in the
+ <command>response-policy</command> option.
+ An organization using a policy zone provided by another
+ organization might use this mechanism to redirect domains
+ to its own walled garden.
+ <variablelist>
+ <varlistentry>
+ <term><command>GIVEN</command></term>
+ <listitem>
+ <para>The placeholder policy says "do not override but
+ perform the action specified in the zone."
+ </para>
+ </listitem>
+ </varlistentry>
- <row rowsep="0">
- <entry colname="1">
- <para>Zone Maintenance Statistics</para>
- </entry>
- <entry colname="2">
- <para>
- Statistics counters regarding zone maintenance
- operations such as zone transfers.
- </para>
- </entry>
- </row>
+ <varlistentry>
+ <term><command>DISABLED</command></term>
+ <listitem>
+ <para>
+ The testing override policy causes policy zone records to do
+ nothing but log what they would have done if the
+ policy zone were not disabled.
+ The response to the DNS query will be written (or not)
+ according to any triggered policy records that are not
+ disabled.
+ Disabled policy zones should appear first,
+ because they will often not be logged
+ if a higher precedence trigger is found first.
+ </para>
+ </listitem>
+ </varlistentry>
- <row rowsep="0">
- <entry colname="1">
- <para>Resolver Statistics</para>
- </entry>
- <entry colname="2">
- <para>
- Statistics counters about name resolution
- performed in the internal resolver.
- Maintained per view.
- </para>
- </entry>
- </row>
+ <varlistentry>
+ <term><command>PASSTHRU</command></term>,
+ <term><command>DROP</command></term>,
+ <term><command>TCP-Only</command></term>,
+ <term><command>NXDOMAIN</command></term>,
+ and
+ <term><command>NODATA</command></term>
+ <listitem>
+ <para>
+ override with the corresponding per-record policy.
+ </para>
+ </listitem>
+ </varlistentry>
- <row rowsep="0">
- <entry colname="1">
- <para>Cache DB RRsets</para>
- </entry>
- <entry colname="2">
- <para>
- The number of RRsets per RR type and nonexistent
- names stored in the cache database.
- If the exclamation mark (!) is printed for a RR
- type, it means that particular type of RRset is
- known to be nonexistent (this is also known as
- "NXRRSET"). If a hash mark (#) is present then
- the RRset is marked for garbage collection.
- Maintained per view.
- </para>
- </entry>
- </row>
+ <varlistentry>
+ <term><command>CNAME domain</command></term>
+ <listitem>
+ <para>
+ causes all RPZ policy records to act as if they were
+ "cname domain" records.
+ </para>
+ </listitem>
+ </varlistentry>
+ </variablelist>
+ </para>
- <row rowsep="0">
- <entry colname="1">
- <para>Socket I/O Statistics</para>
- </entry>
- <entry colname="2">
- <para>
- Statistics counters about network related events.
- </para>
- </entry>
- </row>
+ <para>
+ By default, the actions encoded in a response policy zone
+ are applied only to queries that ask for recursion (RD=1).
+ That default can be changed for a single policy zone or
+ all response policy zones in a view
+ with a <command>recursive-only no</command> clause.
+ This feature is useful for serving the same zone files
+ both inside and outside an RFC 1918 cloud and using RPZ to
+ delete answers that would otherwise contain RFC 1918 values
+ on the externally visible name server or view.
+ </para>
- </tbody>
- </tgroup>
- </informaltable>
+ <para>
+ Also by default, RPZ actions are applied only to DNS requests
+ that either do not request DNSSEC metadata (DO=0) or when no
+ DNSSEC records are available for request name in the original
+ zone (not the response policy zone). This default can be
+ changed for all response policy zones in a view with a
+ <command>break-dnssec yes</command> clause. In that case, RPZ
+ actions are applied regardless of DNSSEC. The name of the
+ clause option reflects the fact that results rewritten by RPZ
+ actions cannot verify.
+ </para>
- <para>
- A subset of Name Server Statistics is collected and shown
- per zone for which the server has the authority when
- <command>zone-statistics</command> is set to
- <userinput>yes</userinput>.
- These statistics counters are shown with their zone and view
- names.
- In some cases the view names are omitted for the default view.
- </para>
+ <para>
+ No DNS records are needed for a QNAME or Client-IP trigger.
+ The name or IP address itself is sufficient,
+ so in principle the query name need not be recursively resolved.
+ However, not resolving the requested
+ name can leak the fact that response policy rewriting is in use
+ and that the name is listed in a policy zone to operators of
+ servers for listed names. To prevent that information leak, by
+ default any recursion needed for a request is done before any
+ policy triggers are considered. Because listed domains often
+ have slow authoritative servers, this default behavior can cost
+ significant time.
+ The <command>qname-wait-recurse no</command> option
+ overrides that default behavior when recursion cannot
+ change a non-error response.
+ The option does not affect QNAME or client-IP triggers
+ in policy zones listed
+ after other zones containing IP, NSIP and NSDNAME triggers, because
+ those may depend on the A, AAAA, and NS records that would be
+ found during recursive resolution. It also does not affect
+ DNSSEC requests (DO=1) unless <command>break-dnssec yes</command>
+ is in use, because the response would depend on whether or not
+ RRSIG records were found during resolution.
+ The option can cause appear to rewrite error responses
+ such as SERVFAIL when no recursion is done to discover problems
+ at the authoritative server.
+ </para>
- <para>
- There are currently two user interfaces to get access to the
- statistics.
- One is in the plain text format dumped to the file specified
- by the <command>statistics-file</command> configuration option.
- The other is remotely accessible via a statistics channel
- when the <command>statistics-channels</command> statement
- is specified in the configuration file
- (see <xref linkend="statschannels"/>.)
- </para>
+ <para>
+ The TTL of a record modified by RPZ policies is set from the
+ TTL of the relevant record in policy zone. It is then limited
+ to a maximum value.
+ The <command>max-policy-ttl</command> clause changes that
+ maximum from its default of 5.
+ </para>
- <sect3 id="statsfile">
- <title>The Statistics File</title>
- <para>
- The text format statistics dump begins with a line, like:
+ <para>
+ For example, you might use this option statement
</para>
- <para>
- <command>+++ Statistics Dump +++ (973798949)</command>
+<programlisting> response-policy { zone "badlist"; };</programlisting>
+ <para>
+ and this zone statement
</para>
+<programlisting> zone "badlist" {type master; file "master/badlist"; allow-query {none;}; };</programlisting>
<para>
- The number in parentheses is a standard
- Unix-style timestamp, measured as seconds since January 1, 1970.
+ with this zone file
+ </para>
+<programlisting>$TTL 1H
+@ SOA LOCALHOST. named-mgr.example.com (1 1h 15m 30d 2h)
+ NS LOCALHOST.
- Following
- that line is a set of statistics information, which is categorized
- as described above.
- Each section begins with a line, like:
+; QNAME policy records. There are no periods (.) after the owner names.
+nxdomain.domain.com CNAME . ; NXDOMAIN policy
+*.nxdomain.domain.com CNAME . ; NXDOMAIN policy
+nodata.domain.com CNAME *. ; NODATA policy
+*.nodata.domain.com CNAME *. ; NODATA policy
+bad.domain.com A 10.0.0.1 ; redirect to a walled garden
+ AAAA 2001:2::1
+bzone.domain.com CNAME garden.example.com.
+
+; do not rewrite (PASSTHRU) OK.DOMAIN.COM
+ok.domain.com CNAME rpz-passthru.
+
+; redirect x.bzone.domain.com to x.bzone.domain.com.garden.example.com
+*.bzone.domain.com CNAME *.garden.example.com.
+
+
+; IP policy records that rewrite all responses containing A records in 127/8
+; except 127.0.0.1
+8.0.0.0.127.rpz-ip CNAME .
+32.1.0.0.127.rpz-ip CNAME rpz-passthru.
+
+; NSDNAME and NSIP policy records
+ns.domain.com.rpz-nsdname CNAME .
+48.zz.2.2001.rpz-nsip CNAME .
+
+; blacklist and whitelist some DNS clients
+112.zz.2001.rpz-client-ip CNAME rpz-drop.
+8.0.0.0.127.rpz-client-ip CNAME rpz-drop.
+
+; force some DNS clients and responses in the example.com zone to TCP
+16.0.0.1.10.rpz-client-ip CNAME rpz-tcp-only.
+example.com CNAME rpz-tcp-only.
+*.example.com CNAME rpz-tcp-only.
+
+</programlisting>
+ <para>
+ RPZ can affect server performance.
+ Each configured response policy zone requires the server to
+ perform one to four additional database lookups before a
+ query can be answered.
+ For example, a DNS server with four policy zones, each with all
+ four kinds of response triggers, QNAME, IP, NSIP, and
+ NSDNAME, requires a total of 17 times as many database
+ lookups as a similar DNS server with no response policy zones.
+ A <acronym>BIND9</acronym> server with adequate memory and one
+ response policy zone with QNAME and IP triggers might achieve a
+ maximum queries-per-second rate about 20% lower.
+ A server with four response policy zones with QNAME and IP
+ triggers might have a maximum QPS rate about 50% lower.
</para>
<para>
- <command>++ Name Server Statistics ++</command>
+ Responses rewritten by RPZ are counted in the
+ <command>RPZRewrites</command> statistics.
</para>
+ </sect3>
+ <sect3>
+ <title>Response Rate Limiting</title>
<para>
- Each section consists of lines, each containing the statistics
- counter value followed by its textual description.
- See below for available counters.
- For brevity, counters that have a value of 0 are not shown
- in the statistics file.
+ Excessive almost identical UDP <emphasis>responses</emphasis>
+ can be controlled by configuring a
+ <command>rate-limit</command> clause in an
+ <command>options</command> or <command>view</command> statement.
+ This mechanism keeps authoritative BIND 9 from being used
+ in amplifying reflection denial of service (DoS) attacks.
+ Short truncated (TC=1) responses can be sent to provide
+ rate-limited responses to legitimate clients within
+ a range of forged, attacked IP addresses.
+ Legitimate clients react to dropped or truncated response
+ by retrying with UDP or with TCP respectively.
</para>
<para>
- The statistics dump ends with the line where the
- number is identical to the number in the beginning line; for example:
- </para>
- <para>
- <command>--- Statistics Dump --- (973798949)</command>
- </para>
- </sect3>
+ This mechanism is intended for authoritative DNS servers.
+ It can be used on recursive servers but can slow
+ applications such as SMTP servers (mail receivers) and
+ HTTP clients (web browsers) that repeatedly request the
+ same domains.
+ When possible, closing "open" recursive servers is better.
+ </para>
- <sect2 id="statistics_counters">
- <title>Statistics Counters</title>
<para>
- The following tables summarize statistics counters that
- <acronym>BIND</acronym> 9 provides.
- For each row of the tables, the leftmost column is the
- abbreviated symbol name of that counter.
- These symbols are shown in the statistics information
- accessed via an HTTP statistics channel.
- The rightmost column gives the description of the counter,
- which is also shown in the statistics file
- (but, in this document, possibly with slight modification
- for better readability).
- Additional notes may also be provided in this column.
- When a middle column exists between these two columns,
- it gives the corresponding counter name of the
- <acronym>BIND</acronym> 8 statistics, if applicable.
+ Response rate limiting uses a "credit" or "token bucket" scheme.
+ Each combination of identical response and client
+ has a conceptual account that earns a specified number
+ of credits every second.
+ A prospective response debits its account by one.
+ Responses are dropped or truncated
+ while the account is negative.
+ Responses are tracked within a rolling window of time
+ which defaults to 15 seconds, but can be configured with
+ the <command>window</command> option to any value from
+ 1 to 3600 seconds (1 hour).
+ The account cannot become more positive than
+ the per-second limit
+ or more negative than <command>window</command>
+ times the per-second limit.
+ When the specified number of credits for a class of
+ responses is set to 0, those responses are not rate limited.
</para>
- <sect3>
- <title>Name Server Statistics Counters</title>
+ <para>
+ The notions of "identical response" and "DNS client"
+ for rate limiting are not simplistic.
+ All responses to an address block are counted as if to a
+ single client.
+ The prefix lengths of addresses blocks are
+ specified with <command>ipv4-prefix-length</command> (default 24)
+ and <command>ipv6-prefix-length</command> (default 56).
+ </para>
- <informaltable colsep="0" rowsep="0">
- <tgroup cols="3" colsep="0" rowsep="0" tgroupstyle="4Level-table">
- <colspec colname="1" colnum="1" colsep="0" colwidth="1.150in"/>
- <colspec colname="2" colnum="2" colsep="0" colwidth="1.150in"/>
- <colspec colname="3" colnum="3" colsep="0" colwidth="3.350in"/>
- <tbody>
- <row>
- <entry colname="1">
- <para>
- <emphasis>Symbol</emphasis>
- </para>
- </entry>
- <entry colname="2">
- <para>
- <emphasis>BIND8 Symbol</emphasis>
- </para>
- </entry>
- <entry colname="3">
- <para>
- <emphasis>Description</emphasis>
- </para>
- </entry>
- </row>
+ <para>
+ All non-empty responses for a valid domain name (qname)
+ and record type (qtype) are identical and have a limit specified
+ with <command>responses-per-second</command>
+ (default 0 or no limit).
+ All empty (NODATA) responses for a valid domain,
+ regardless of query type, are identical.
+ Responses in the NODATA class are limited by
+ <command>nodata-per-second</command>
+ (default <command>responses-per-second</command>).
+ Requests for any and all undefined subdomains of a given
+ valid domain result in NXDOMAIN errors, and are identical
+ regardless of query type.
+ They are limited by <command>nxdomain-per-second</command>
+ (default <command>responses-per-second</command>).
+ This controls some attacks using random names, but
+ can be relaxed or turned off (set to 0)
+ on servers that expect many legitimate
+ NXDOMAIN responses, such as from anti-spam blacklists.
+ Referrals or delegations to the server of a given
+ domain are identical and are limited by
+ <command>referrals-per-second</command>
+ (default <command>responses-per-second</command>).
+ </para>
- <row rowsep="0">
- <entry colname="1">
- <para><command>Requestv4</command></para>
- </entry>
- <entry colname="2">
- <para><command>RQ</command></para>
- </entry>
- <entry colname="3">
- <para>
- IPv4 requests received.
- Note: this also counts non query requests.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para><command>Requestv6</command></para>
- </entry>
- <entry colname="2">
- <para><command>RQ</command></para>
- </entry>
- <entry colname="3">
- <para>
- IPv6 requests received.
- Note: this also counts non query requests.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para><command>ReqEdns0</command></para>
- </entry>
- <entry colname="2">
- <para><command></command></para>
- </entry>
- <entry colname="3">
- <para>
- Requests with EDNS(0) received.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para><command>ReqBadEDNSVer</command></para>
- </entry>
- <entry colname="2">
- <para><command></command></para>
- </entry>
- <entry colname="3">
- <para>
- Requests with unsupported EDNS version received.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para><command>ReqTSIG</command></para>
- </entry>
- <entry colname="2">
- <para><command></command></para>
- </entry>
- <entry colname="3">
- <para>
- Requests with TSIG received.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para><command>ReqSIG0</command></para>
- </entry>
- <entry colname="2">
- <para><command></command></para>
- </entry>
- <entry colname="3">
- <para>
- Requests with SIG(0) received.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para><command>ReqBadSIG</command></para>
- </entry>
- <entry colname="2">
- <para><command></command></para>
- </entry>
- <entry colname="3">
- <para>
- Requests with invalid (TSIG or SIG(0)) signature.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para><command>ReqTCP</command></para>
- </entry>
- <entry colname="2">
- <para><command>RTCP</command></para>
- </entry>
- <entry colname="3">
- <para>
- TCP requests received.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para><command>AuthQryRej</command></para>
- </entry>
- <entry colname="2">
- <para><command>RUQ</command></para>
- </entry>
- <entry colname="3">
- <para>
- Authoritative (non recursive) queries rejected.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para><command>RecQryRej</command></para>
- </entry>
- <entry colname="2">
- <para><command>RURQ</command></para>
- </entry>
- <entry colname="3">
- <para>
- Recursive queries rejected.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para><command>XfrRej</command></para>
- </entry>
- <entry colname="2">
- <para><command>RUXFR</command></para>
- </entry>
- <entry colname="3">
- <para>
- Zone transfer requests rejected.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para><command>UpdateRej</command></para>
- </entry>
- <entry colname="2">
- <para><command>RUUpd</command></para>
- </entry>
- <entry colname="3">
- <para>
- Dynamic update requests rejected.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para><command>Response</command></para>
- </entry>
- <entry colname="2">
- <para><command>SAns</command></para>
- </entry>
- <entry colname="3">
- <para>
- Responses sent.
- </para>
- </entry>
- </row>
- <row rowsep="0">
- <entry colname="1">
- <para><command>RespTruncated</command></para>
- </entry>
- <entry colname="2">
- <para><command></command></para>
- </entry>
- <entry colname="3">
- <para>
- Truncated responses sent.
- </para>
- </entry>
- </row>
- <row rowsep="0">
+ <para>
+ Responses generated from local wildcards are counted and limited
+ as if they were for the parent domain name.
+ This controls flooding using random.wild.example.com.
+ </para>
+
+ <para>
+ All requests that result in DNS errors other
+ than NXDOMAIN, such as SERVFAIL and FORMERR, are identical
+ regardless of requested name (qname) or record type (qtype).
+ This controls attacks using invalid requests or distant,
+ broken authoritative servers.
+ By default the limit on errors is the same as the
+ <command>responses-per-second</command> value,
+ but it can be set separately with
+ <command>errors-per-second</command>.
+ </para>
+
+ <para>
+ Many attacks using DNS involve UDP requests with forged source
+ addresses.
+ Rate limiting prevents the use of BIND 9 to flood a network
+ with responses to requests with forged source addresses,
+ but could let a third party block responses to legitimate requests.
+ There is a mechanism that can answer some legitimate
+ requests from a client whose address is being forged in a flood.
+ Setting <command>slip</command> to 2 (its default) causes every
+ other UDP request to be answered with a small truncated (TC=1)
+ response.
+ The small size and reduced frequency, and so lack of
+ amplification, of "slipped" responses make them unattractive
+ for reflection DoS attacks.
+ <command>slip</command> must be between 0 and 10.
+ A value of 0 does not "slip":
+ no truncated responses are sent due to rate limiting,
+ all responses are dropped.
+ A value of 1 causes every response to slip;
+ values between 2 and 10 cause every n'th response to slip.
+ Some error responses including REFUSED and SERVFAIL
+ cannot be replaced with truncated responses and are instead
+ leaked at the <command>slip</command> rate.
+ </para>
+
+ <para>
+ (NOTE: Dropped responses from an authoritative server may
+ reduce the difficulty of a third party successfully forging
+ a response to a recursive resolver. The best security
+ against forged responses is for authoritative operators
+ to sign their zones using DNSSEC and for resolver operators
+ to validate the responses. When this is not an option,
+ operators who are more concerned with response integrity
+ than with flood mitigation may consider setting
+ <command>slip</command> to 1, causing all rate-limited
+ responses to be truncated rather than dropped. This reduces
+ the effectiveness of rate-limiting against reflection attacks.)
+ </para>
+
+ <para>
+ When the approximate query per second rate exceeds
+ the <command>qps-scale</command> value,
+ then the <command>responses-per-second</command>,
+ <command>errors-per-second</command>,
+ <command>nxdomains-per-second</command> and
+ <command>all-per-second</command> values are reduced by the
+ ratio of the current rate to the <command>qps-scale</command> value.
+ This feature can tighten defenses during attacks.
+ For example, with
+ <command>qps-scale 250; responses-per-second 20;</command> and
+ a total query rate of 1000 queries/second for all queries from
+ all DNS clients including via TCP,
+ then the effective responses/second limit changes to
+ (250/1000)*20 or 5.
+ Responses sent via TCP are not limited
+ but are counted to compute the query per second rate.
+ </para>
+
+ <para>
+ Communities of DNS clients can be given their own parameters or no
+ rate limiting by putting
+ <command>rate-limit</command> statements in <command>view</command>
+ statements instead of the global <command>option</command>
+ statement.
+ A <command>rate-limit</command> statement in a view replaces,
+ rather than supplementing, a <command>rate-limit</command>
+ statement among the main options.
+ DNS clients within a view can be exempted from rate limits
+ with the <command>exempt-clients</command> clause.
+ </para>
+
+ <para>
+ UDP responses of all kinds can be limited with the
+ <command>all-per-second</command> phrase.
+ This rate limiting is unlike the rate limiting provided by
+ <command>responses-per-second</command>,
+ <command>errors-per-second</command>, and
+ <command>nxdomains-per-second</command> on a DNS server
+ which are often invisible to the victim of a DNS reflection attack.
+ Unless the forged requests of the attack are the same as the
+ legitimate requests of the victim, the victim's requests are
+ not affected.
+ Responses affected by an <command>all-per-second</command> limit
+ are always dropped; the <command>slip</command> value has no
+ effect.
+ An <command>all-per-second</command> limit should be
+ at least 4 times as large as the other limits,
+ because single DNS clients often send bursts of legitimate
+ requests.
+ For example, the receipt of a single mail message can prompt
+ requests from an SMTP server for NS, PTR, A, and AAAA records
+ as the incoming SMTP/TCP/IP connection is considered.
+ The SMTP server can need additional NS, A, AAAA, MX, TXT, and SPF
+ records as it considers the STMP <command>Mail From</command>
+ command.
+ Web browsers often repeatedly resolve the same names that
+ are repeated in HTML <IMG> tags in a page.
+ <command>All-per-second</command> is similar to the
+ rate limiting offered by firewalls but often inferior.
+ Attacks that justify ignoring the
+ contents of DNS responses are likely to be attacks on the
+ DNS server itself.
+ They usually should be discarded before the DNS server
+ spends resources making TCP connections or parsing DNS requests,
+ but that rate limiting must be done before the
+ DNS server sees the requests.
+ </para>
+
+ <para>
+ The maximum size of the table used to track requests and
+ rate limit responses is set with <command>max-table-size</command>.
+ Each entry in the table is between 40 and 80 bytes.
+ The table needs approximately as many entries as the number
+ of requests received per second.
+ The default is 20,000.
+ To reduce the cold start of growing the table,
+ <command>min-table-size</command> (default 500)
+ can set the minimum table size.
+ Enable <command>rate-limit</command> category logging to monitor
+ expansions of the table and inform
+ choices for the initial and maximum table size.
+ </para>
+
+ <para>
+ Use <command>log-only yes</command> to test rate limiting parameters
+ without actually dropping any requests.
+ </para>
+
+ <para>
+ Responses dropped by rate limits are included in the
+ <command>RateDropped</command> and <command>QryDropped</command>
+ statistics.
+ Responses that truncated by rate limits are included in
+ <command>RateSlipped</command> and <command>RespTruncated</command>.
+ </para>
+ </sect3>
+ </sect2>
+
+ <sect2 id="server_statement_grammar">
+ <title><command>server</command> Statement Grammar</title>
+
+<programlisting><command>server</command> <replaceable>ip_addr[/prefixlen]</replaceable> {
+ <optional> bogus <replaceable>yes_or_no</replaceable> ; </optional>
+ <optional> provide-ixfr <replaceable>yes_or_no</replaceable> ; </optional>
+ <optional> request-ixfr <replaceable>yes_or_no</replaceable> ; </optional>
+ <optional> edns <replaceable>yes_or_no</replaceable> ; </optional>
+ <optional> edns-udp-size <replaceable>number</replaceable> ; </optional>
+ <optional> max-udp-size <replaceable>number</replaceable> ; </optional>
+ <optional> transfers <replaceable>number</replaceable> ; </optional>
+ <optional> transfer-format <replaceable>( one-answer | many-answers )</replaceable> ; ]</optional>
+ <optional> keys <replaceable>{ string ; <optional> string ; <optional>...</optional></optional> }</replaceable> ; </optional>
+ <optional> transfer-source (<replaceable>ip4_addr</replaceable> | <constant>*</constant>) <optional>port <replaceable>ip_port</replaceable></optional> <optional>dscp <replaceable>ip_dscp</replaceable></optional> ; </optional>
+ <optional> transfer-source-v6 (<replaceable>ip6_addr</replaceable> | <constant>*</constant>) <optional>port <replaceable>ip_port</replaceable></optional> <optional>dscp <replaceable>ip_dscp</replaceable></optional> ; </optional>
+ <optional> notify-source (<replaceable>ip4_addr</replaceable> | <constant>*</constant>) <optional>port <replaceable>ip_port</replaceable></optional> <optional>dscp <replaceable>ip_dscp</replaceable></optional> ; </optional>
+ <optional> notify-source-v6 (<replaceable>ip6_addr</replaceable> | <constant>*</constant>) <optional>port <replaceable>ip_port</replaceable></optional> <optional>dscp <replaceable>ip_dscp</replaceable></optional> ; </optional>
+ <optional> query-source <optional> address ( <replaceable>ip_addr</replaceable> | <replaceable>*</replaceable> ) </optional>
+ <optional> port ( <replaceable>ip_port</replaceable> | <replaceable>*</replaceable> ) </optional> <optional>dscp <replaceable>ip_dscp</replaceable></optional> ; </optional>
+ <optional> query-source-v6 <optional> address ( <replaceable>ip_addr</replaceable> | <replaceable>*</replaceable> ) </optional>
+ <optional> port ( <replaceable>ip_port</replaceable> | <replaceable>*</replaceable> ) </optional> <optional>dscp <replaceable>ip_dscp</replaceable></optional> ; </optional>
+ <optional> use-queryport-pool <replaceable>yes_or_no</replaceable>; </optional>
+ <optional> queryport-pool-ports <replaceable>number</replaceable>; </optional>
+ <optional> queryport-pool-updateinterval <replaceable>number</replaceable>; </optional>
+};
+</programlisting>
+
+ </sect2>
+
+ <sect2 id="server_statement_definition_and_usage">
+ <title><command>server</command> Statement Definition and
+ Usage</title>
+
+ <para>
+ The <command>server</command> statement defines
+ characteristics
+ to be associated with a remote name server. If a prefix length is
+ specified, then a range of servers is covered. Only the most
+ specific
+ server clause applies regardless of the order in
+ <filename>named.conf</filename>.
+ </para>
+
+ <para>
+ The <command>server</command> statement can occur at
+ the top level of the
+ configuration file or inside a <command>view</command>
+ statement.
+ If a <command>view</command> statement contains
+ one or more <command>server</command> statements, only
+ those
+ apply to the view and any top-level ones are ignored.
+ If a view contains no <command>server</command>
+ statements,
+ any top-level <command>server</command> statements are
+ used as
+ defaults.
+ </para>
+
+ <para>
+ If you discover that a remote server is giving out bad data,
+ marking it as bogus will prevent further queries to it. The
+ default
+ value of <command>bogus</command> is <command>no</command>.
+ </para>
+ <para>
+ The <command>provide-ixfr</command> clause determines
+ whether
+ the local server, acting as master, will respond with an
+ incremental
+ zone transfer when the given remote server, a slave, requests it.
+ If set to <command>yes</command>, incremental transfer
+ will be provided
+ whenever possible. If set to <command>no</command>,
+ all transfers
+ to the remote server will be non-incremental. If not set, the
+ value
+ of the <command>provide-ixfr</command> option in the
+ view or
+ global options block is used as a default.
+ </para>
+
+ <para>
+ The <command>request-ixfr</command> clause determines
+ whether
+ the local server, acting as a slave, will request incremental zone
+ transfers from the given remote server, a master. If not set, the
+ value of the <command>request-ixfr</command> option in
+ the view or global options block is used as a default. It may
+ also be set in the zone block and, if set there, it will
+ override the global or view setting for that zone.
+ </para>
+
+ <para>
+ IXFR requests to servers that do not support IXFR will
+ automatically
+ fall back to AXFR. Therefore, there is no need to manually list
+ which servers support IXFR and which ones do not; the global
+ default
+ of <command>yes</command> should always work.
+ The purpose of the <command>provide-ixfr</command> and
+ <command>request-ixfr</command> clauses is
+ to make it possible to disable the use of IXFR even when both
+ master
+ and slave claim to support it, for example if one of the servers
+ is buggy and crashes or corrupts data when IXFR is used.
+ </para>
+
+ <para>
+ The <command>edns</command> clause determines whether
+ the local server will attempt to use EDNS when communicating
+ with the remote server. The default is <command>yes</command>.
+ </para>
+
+ <para>
+ The <command>edns-udp-size</command> option sets the EDNS UDP size
+ that is advertised by <command>named</command> when querying the remote server.
+ Valid values are 512 to 4096 bytes (values outside this range will be
+ silently adjusted). This option is useful when you wish to
+ advertises a different value to this server than the value you
+ advertise globally, for example, when there is a firewall at the
+ remote site that is blocking large replies.
+ </para>
+
+ <para>
+ The <command>max-udp-size</command> option sets the
+ maximum EDNS UDP message size <command>named</command> will send. Valid
+ values are 512 to 4096 bytes (values outside this range will
+ be silently adjusted). This option is useful when you
+ know that there is a firewall that is blocking large
+ replies from <command>named</command>.
+ </para>
+
+ <para>
+ The server supports two zone transfer methods. The first, <command>one-answer</command>,
+ uses one DNS message per resource record transferred. <command>many-answers</command> packs
+ as many resource records as possible into a message. <command>many-answers</command> is
+ more efficient, but is only known to be understood by <acronym>BIND</acronym> 9, <acronym>BIND</acronym>
+ 8.x, and patched versions of <acronym>BIND</acronym>
+ 4.9.5. You can specify which method
+ to use for a server with the <command>transfer-format</command> option.
+ If <command>transfer-format</command> is not
+ specified, the <command>transfer-format</command>
+ specified
+ by the <command>options</command> statement will be
+ used.
+ </para>
+
+ <para><command>transfers</command>
+ is used to limit the number of concurrent inbound zone
+ transfers from the specified server. If no
+ <command>transfers</command> clause is specified, the
+ limit is set according to the
+ <command>transfers-per-ns</command> option.
+ </para>
+
+ <para>
+ The <command>keys</command> clause identifies a
+ <command>key_id</command> defined by the <command>key</command> statement,
+ to be used for transaction security (TSIG, <xref linkend="tsig"/>)
+ when talking to the remote server.
+ When a request is sent to the remote server, a request signature
+ will be generated using the key specified here and appended to the
+ message. A request originating from the remote server is not
+ required
+ to be signed by this key.
+ </para>
+
+ <para>
+ Although the grammar of the <command>keys</command>
+ clause
+ allows for multiple keys, only a single key per server is
+ currently
+ supported.
+ </para>
+
+ <para>
+ The <command>transfer-source</command> and
+ <command>transfer-source-v6</command> clauses specify
+ the IPv4 and IPv6 source
+ address to be used for zone transfer with the remote server,
+ respectively.
+ For an IPv4 remote server, only <command>transfer-source</command> can
+ be specified.
+ Similarly, for an IPv6 remote server, only
+ <command>transfer-source-v6</command> can be
+ specified.
+ For more details, see the description of
+ <command>transfer-source</command> and
+ <command>transfer-source-v6</command> in
+ <xref linkend="zone_transfers"/>.
+ </para>
+
+ <para>
+ The <command>notify-source</command> and
+ <command>notify-source-v6</command> clauses specify the
+ IPv4 and IPv6 source address to be used for notify
+ messages sent to remote servers, respectively. For an
+ IPv4 remote server, only <command>notify-source</command>
+ can be specified. Similarly, for an IPv6 remote server,
+ only <command>notify-source-v6</command> can be specified.
+ </para>
+
+ <para>
+ The <command>query-source</command> and
+ <command>query-source-v6</command> clauses specify the
+ IPv4 and IPv6 source address to be used for queries
+ sent to remote servers, respectively. For an IPv4
+ remote server, only <command>query-source</command> can
+ be specified. Similarly, for an IPv6 remote server,
+ only <command>query-source-v6</command> can be specified.
+ </para>
+
+ </sect2>
+
+ <sect2 id="statschannels">
+ <title><command>statistics-channels</command> Statement Grammar</title>
+
+<programlisting><command>statistics-channels</command> {
+ [ inet ( ip_addr | * ) [ port ip_port ]
+ [ allow { <replaceable> address_match_list </replaceable> } ]; ]
+ [ inet ...; ]
+};
+</programlisting>
+ </sect2>
+
+ <sect2>
+ <title><command>statistics-channels</command> Statement Definition and
+ Usage</title>
+
+ <para>
+ The <command>statistics-channels</command> statement
+ declares communication channels to be used by system
+ administrators to get access to statistics information of
+ the name server.
+ </para>
+
+ <para>
+ This statement intends to be flexible to support multiple
+ communication protocols in the future, but currently only
+ HTTP access is supported.
+ It requires that BIND 9 be compiled with libxml2 and/or
+ json-c (also known as libjson0); the
+ <command>statistics-channels</command> statement is
+ still accepted even if it is built without the library,
+ but any HTTP access will fail with an error.
+ </para>
+
+ <para>
+ An <command>inet</command> control channel is a TCP socket
+ listening at the specified <command>ip_port</command> on the
+ specified <command>ip_addr</command>, which can be an IPv4 or IPv6
+ address. An <command>ip_addr</command> of <literal>*</literal>
+ (asterisk) is
+ interpreted as the IPv4 wildcard address; connections will be
+ accepted on any of the system's IPv4 addresses.
+ To listen on the IPv6 wildcard address,
+ use an <command>ip_addr</command> of <literal>::</literal>.
+ </para>
+
+ <para>
+ If no port is specified, port 80 is used for HTTP channels.
+ The asterisk "<literal>*</literal>" cannot be used for
+ <command>ip_port</command>.
+ </para>
+
+ <para>
+ The attempt of opening a statistics channel is
+ restricted by the optional <command>allow</command> clause.
+ Connections to the statistics channel are permitted based on the
+ <command>address_match_list</command>.
+ If no <command>allow</command> clause is present,
+ <command>named</command> accepts connection
+ attempts from any address; since the statistics may
+ contain sensitive internal information, it is highly
+ recommended to restrict the source of connection requests
+ appropriately.
+ </para>
+
+ <para>
+ If no <command>statistics-channels</command> statement is present,
+ <command>named</command> will not open any communication channels.
+ </para>
+
+ <para>
+ The statistics are available in various formats and views
+ depending on the URI used to access them. For example, if
+ the statistics channel is configured to listen on 127.0.0.1
+ port 8888, then the statistics are accessible in XML format at
+ <ulink url="http://127.0.0.1:8888/"
+ >http://127.0.0.1:8888/</ulink> or
+ <ulink url="http://127.0.0.1:8888/xml"
+ >http://127.0.0.1:8888/xml</ulink>. A CSS file is
+ included which can format the XML statistics into tables
+ when viewed with a stylesheet-capable browser, and into
+ charts and graphs using the Google Charts API when using a
+ javascript-capable browser.
+ </para>
+
+ <para>
+ Applications that depend on a particular XML schema
+ can request
+ <ulink url="http://127.0.0.1:8888/xml/v2"
+ >http://127.0.0.1:8888/xml/v2</ulink> for version 2
+ of the statistics XML schema or
+ <ulink url="http://127.0.0.1:8888/xml/v3"
+ >http://127.0.0.1:8888/xml/v3</ulink> for version 3.
+ If the requested schema is supported by the server, then
+ it will respond; if not, it will return a "page not found"
+ error.
+ </para>
+
+ <para>
+ Broken-out subsets of the statistics can be viewed at
+ <ulink url="http://127.0.0.1:8888/xml/v3/status"
+ >http://127.0.0.1:8888/xml/v3/status</ulink>
+ (server uptime and last reconfiguration time),
+ <ulink url="http://127.0.0.1:8888/xml/v3/server"
+ >http://127.0.0.1:8888/xml/v3/server</ulink>
+ (server and resolver statistics),
+ <ulink url="http://127.0.0.1:8888/xml/v3/zones"
+ >http://127.0.0.1:8888/xml/v3/zones</ulink>
+ (zone statistics),
+ <ulink url="http://127.0.0.1:8888/xml/v3/net"
+ >http://127.0.0.1:8888/xml/v3/net</ulink>
+ (network status and socket statistics),
+ <ulink url="http://127.0.0.1:8888/xml/v3/mem"
+ >http://127.0.0.1:8888/xml/v3/mem</ulink>
+ (memory manager statistics),
+ <ulink url="http://127.0.0.1:8888/xml/v3/tasks"
+ >http://127.0.0.1:8888/xml/v3/tasks</ulink>
+ (task manager statistics).
+ </para>
+
+ <para>
+ The full set of statistics can also be read in JSON format at
+ <ulink url="http://127.0.0.1:8888/json"
+ >http://127.0.0.1:8888/json</ulink>,
+ with the broken-out subsets at
+ <ulink url="http://127.0.0.1:8888/json/v1/status"
+ >http://127.0.0.1:8888/json/v1/status</ulink>
+ (server uptime and last reconfiguration time),
+ <ulink url="http://127.0.0.1:8888/json/v1/server"
+ >http://127.0.0.1:8888/json/v1/server</ulink>
+ (server and resolver statistics),
+ <ulink url="http://127.0.0.1:8888/json/v1/zones"
+ >http://127.0.0.1:8888/json/v1/zones</ulink>
+ (zone statistics),
+ <ulink url="http://127.0.0.1:8888/json/v1/net"
+ >http://127.0.0.1:8888/json/v1/net</ulink>
+ (network status and socket statistics),
+ <ulink url="http://127.0.0.1:8888/json/v1/mem"
+ >http://127.0.0.1:8888/json/v1/mem</ulink>
+ (memory manager statistics),
+ <ulink url="http://127.0.0.1:8888/json/v1/tasks"
+ >http://127.0.0.1:8888/json/v1/tasks</ulink>
+ (task manager statistics).
+ </para>
+ </sect2>
+
+ <sect2 id="trusted-keys">
+ <title><command>trusted-keys</command> Statement Grammar</title>
+
+<programlisting><command>trusted-keys</command> {
+ <replaceable>string</replaceable> <replaceable>number</replaceable> <replaceable>number</replaceable> <replaceable>number</replaceable> <replaceable>string</replaceable> ;
+ <optional> <replaceable>string</replaceable> <replaceable>number</replaceable> <replaceable>number</replaceable> <replaceable>number</replaceable> <replaceable>string</replaceable> ; <optional>...</optional></optional>
+};
+</programlisting>
+
+ </sect2>
+ <sect2>
+ <title><command>trusted-keys</command> Statement Definition
+ and Usage</title>
+ <para>
+ The <command>trusted-keys</command> statement defines
+ DNSSEC security roots. DNSSEC is described in <xref
+ linkend="DNSSEC"/>. A security root is defined when the
+ public key for a non-authoritative zone is known, but
+ cannot be securely obtained through DNS, either because
+ it is the DNS root zone or because its parent zone is
+ unsigned. Once a key has been configured as a trusted
+ key, it is treated as if it had been validated and
+ proven secure. The resolver attempts DNSSEC validation
+ on all DNS data in subdomains of a security root.
+ </para>
+ <para>
+ All keys (and corresponding zones) listed in
+ <command>trusted-keys</command> are deemed to exist regardless
+ of what parent zones say. Similarly for all keys listed in
+ <command>trusted-keys</command> only those keys are
+ used to validate the DNSKEY RRset. The parent's DS RRset
+ will not be used.
+ </para>
+ <para>
+ The <command>trusted-keys</command> statement can contain
+ multiple key entries, each consisting of the key's
+ domain name, flags, protocol, algorithm, and the Base-64
+ representation of the key data.
+ Spaces, tabs, newlines and carriage returns are ignored
+ in the key data, so the configuration may be split up into
+ multiple lines.
+ </para>
+ <para>
+ <command>trusted-keys</command> may be set at the top level
+ of <filename>named.conf</filename> or within a view. If it is
+ set in both places, they are additive: keys defined at the top
+ level are inherited by all views, but keys defined in a view
+ are only used within that view.
+ </para>
+ </sect2>
+
+ <sect2>
+ <title><command>managed-keys</command> Statement Grammar</title>
+
+<programlisting><command>managed-keys</command> {
+ <replaceable>name</replaceable> <literal>initial-key</literal> <replaceable>flags</replaceable> <replaceable>protocol</replaceable> <replaceable>algorithm</replaceable> <replaceable>key-data</replaceable> ;
+ <optional> <replaceable>name</replaceable> <literal>initial-key</literal> <replaceable>flags</replaceable> <replaceable>protocol</replaceable> <replaceable>algorithm</replaceable> <replaceable>key-data</replaceable> ; <optional>...</optional></optional>
+};
+</programlisting>
+
+ </sect2>
+ <sect2 id="managed-keys">
+ <title><command>managed-keys</command> Statement Definition
+ and Usage</title>
+ <para>
+ The <command>managed-keys</command> statement, like
+ <command>trusted-keys</command>, defines DNSSEC
+ security roots. The difference is that
+ <command>managed-keys</command> can be kept up to date
+ automatically, without intervention from the resolver
+ operator.
+ </para>
+ <para>
+ Suppose, for example, that a zone's key-signing
+ key was compromised, and the zone owner had to revoke and
+ replace the key. A resolver which had the old key in a
+ <command>trusted-keys</command> statement would be
+ unable to validate this zone any longer; it would
+ reply with a SERVFAIL response code. This would
+ continue until the resolver operator had updated the
+ <command>trusted-keys</command> statement with the new key.
+ </para>
+ <para>
+ If, however, the zone were listed in a
+ <command>managed-keys</command> statement instead, then the
+ zone owner could add a "stand-by" key to the zone in advance.
+ <command>named</command> would store the stand-by key, and
+ when the original key was revoked, <command>named</command>
+ would be able to transition smoothly to the new key. It would
+ also recognize that the old key had been revoked, and cease
+ using that key to validate answers, minimizing the damage that
+ the compromised key could do.
+ </para>
+ <para>
+ A <command>managed-keys</command> statement contains a list of
+ the keys to be managed, along with information about how the
+ keys are to be initialized for the first time. The only
+ initialization method currently supported (as of
+ <acronym>BIND</acronym> 9.7.0) is <literal>initial-key</literal>.
+ This means the <command>managed-keys</command> statement must
+ contain a copy of the initializing key. (Future releases may
+ allow keys to be initialized by other methods, eliminating this
+ requirement.)
+ </para>
+ <para>
+ Consequently, a <command>managed-keys</command> statement
+ appears similar to a <command>trusted-keys</command>, differing
+ in the presence of the second field, containing the keyword
+ <literal>initial-key</literal>. The difference is, whereas the
+ keys listed in a <command>trusted-keys</command> continue to be
+ trusted until they are removed from
+ <filename>named.conf</filename>, an initializing key listed
+ in a <command>managed-keys</command> statement is only trusted
+ <emphasis>once</emphasis>: for as long as it takes to load the
+ managed key database and start the RFC 5011 key maintenance
+ process.
+ </para>
+ <para>
+ The first time <command>named</command> runs with a managed key
+ configured in <filename>named.conf</filename>, it fetches the
+ DNSKEY RRset directly from the zone apex, and validates it
+ using the key specified in the <command>managed-keys</command>
+ statement. If the DNSKEY RRset is validly signed, then it is
+ used as the basis for a new managed keys database.
+ </para>
+ <para>
+ From that point on, whenever <command>named</command> runs, it
+ sees the <command>managed-keys</command> statement, checks to
+ make sure RFC 5011 key maintenance has already been initialized
+ for the specified domain, and if so, it simply moves on. The
+ key specified in the <command>managed-keys</command> is not
+ used to validate answers; it has been superseded by the key or
+ keys stored in the managed keys database.
+ </para>
+ <para>
+ The next time <command>named</command> runs after a name
+ has been <emphasis>removed</emphasis> from the
+ <command>managed-keys</command> statement, the corresponding
+ zone will be removed from the managed keys database,
+ and RFC 5011 key maintenance will no longer be used for that
+ domain.
+ </para>
+ <para>
+ <command>named</command> only maintains a single managed keys
+ database; consequently, unlike <command>trusted-keys</command>,
+ <command>managed-keys</command> may only be set at the top
+ level of <filename>named.conf</filename>, not within a view.
+ </para>
+ <para>
+ In the current implementation, the managed keys database is
+ stored as a master-format zone file called
+ <filename>managed-keys.bind</filename>. When the key database
+ is changed, the zone is updated. As with any other dynamic
+ zone, changes will be written into a journal file,
+ <filename>managed-keys.bind.jnl</filename>. They are committed
+ to the master file as soon as possible afterward; in the case
+ of the managed key database, this will usually occur within 30
+ seconds. So, whenever <command>named</command> is using
+ automatic key maintenance, those two files can be expected to
+ exist in the working directory. (For this reason among others,
+ the working directory should be always be writable by
+ <command>named</command>.)
+ </para>
+ <para>
+ If the <command>dnssec-validation</command> option is
+ set to <userinput>auto</userinput>, <command>named</command>
+ will automatically initialize a managed key for the
+ root zone. Similarly, if the <command>dnssec-lookaside</command>
+ option is set to <userinput>auto</userinput>,
+ <command>named</command> will automatically initialize
+ a managed key for the zone <literal>dlv.isc.org</literal>.
+ In both cases, the key that is used to initialize the key
+ maintenance process is built into <command>named</command>,
+ and can be overridden from <command>bindkeys-file</command>.
+ </para>
+ </sect2>
+
+ <sect2 id="view_statement_grammar">
+ <title><command>view</command> Statement Grammar</title>
+
+<programlisting><command>view</command> <replaceable>view_name</replaceable>
+ <optional><replaceable>class</replaceable></optional> {
+ match-clients { <replaceable>address_match_list</replaceable> };
+ match-destinations { <replaceable>address_match_list</replaceable> };
+ match-recursive-only <replaceable>yes_or_no</replaceable> ;
+ <optional> <replaceable>view_option</replaceable>; ...</optional>
+ <optional> <replaceable>zone_statement</replaceable>; ...</optional>
+};
+</programlisting>
+
+ </sect2>
+ <sect2>
+ <title><command>view</command> Statement Definition and Usage</title>
+
+ <para>
+ The <command>view</command> statement is a powerful
+ feature
+ of <acronym>BIND</acronym> 9 that lets a name server
+ answer a DNS query differently
+ depending on who is asking. It is particularly useful for
+ implementing
+ split DNS setups without having to run multiple servers.
+ </para>
+
+ <para>
+ Each <command>view</command> statement defines a view
+ of the
+ DNS namespace that will be seen by a subset of clients. A client
+ matches
+ a view if its source IP address matches the
+ <varname>address_match_list</varname> of the view's
+ <command>match-clients</command> clause and its
+ destination IP address matches
+ the <varname>address_match_list</varname> of the
+ view's
+ <command>match-destinations</command> clause. If not
+ specified, both
+ <command>match-clients</command> and <command>match-destinations</command>
+ default to matching all addresses. In addition to checking IP
+ addresses
+ <command>match-clients</command> and <command>match-destinations</command>
+ can also take <command>keys</command> which provide an
+ mechanism for the
+ client to select the view. A view can also be specified
+ as <command>match-recursive-only</command>, which
+ means that only recursive
+ requests from matching clients will match that view.
+ The order of the <command>view</command> statements is
+ significant —
+ a client request will be resolved in the context of the first
+ <command>view</command> that it matches.
+ </para>
+
+ <para>
+ Zones defined within a <command>view</command>
+ statement will
+ only be accessible to clients that match the <command>view</command>.
+ By defining a zone of the same name in multiple views, different
+ zone data can be given to different clients, for example,
+ "internal"
+ and "external" clients in a split DNS setup.
+ </para>
+
+ <para>
+ Many of the options given in the <command>options</command> statement
+ can also be used within a <command>view</command>
+ statement, and then
+ apply only when resolving queries with that view. When no
+ view-specific
+ value is given, the value in the <command>options</command> statement
+ is used as a default. Also, zone options can have default values
+ specified
+ in the <command>view</command> statement; these
+ view-specific defaults
+ take precedence over those in the <command>options</command> statement.
+ </para>
+
+ <para>
+ Views are class specific. If no class is given, class IN
+ is assumed. Note that all non-IN views must contain a hint zone,
+ since only the IN class has compiled-in default hints.
+ </para>
+
+ <para>
+ If there are no <command>view</command> statements in
+ the config
+ file, a default view that matches any client is automatically
+ created
+ in class IN. Any <command>zone</command> statements
+ specified on
+ the top level of the configuration file are considered to be part
+ of
+ this default view, and the <command>options</command>
+ statement will
+ apply to the default view. If any explicit <command>view</command>
+ statements are present, all <command>zone</command>
+ statements must
+ occur inside <command>view</command> statements.
+ </para>
+
+ <para>
+ Here is an example of a typical split DNS setup implemented
+ using <command>view</command> statements:
+ </para>
+
+<programlisting>view "internal" {
+ // This should match our internal networks.
+ match-clients { 10.0.0.0/8; };
+
+ // Provide recursive service to internal
+ // clients only.
+ recursion yes;
+
+ // Provide a complete view of the example.com
+ // zone including addresses of internal hosts.
+ zone "example.com" {
+ type master;
+ file "example-internal.db";
+ };
+};
+
+view "external" {
+ // Match all clients not matched by the
+ // previous view.
+ match-clients { any; };
+
+ // Refuse recursive service to external clients.
+ recursion no;
+
+ // Provide a restricted view of the example.com
+ // zone containing only publicly accessible hosts.
+ zone "example.com" {
+ type master;
+ file "example-external.db";
+ };
+};
+</programlisting>
+
+ </sect2>
+ <sect2 id="zone_statement_grammar">
+ <title><command>zone</command>
+ Statement Grammar</title>
+
+<programlisting><command>zone</command> <replaceable>zone_name</replaceable> <optional><replaceable>class</replaceable></optional> {
+ type master;
+ <optional> allow-query { <replaceable>address_match_list</replaceable> }; </optional>
+ <optional> allow-query-on { <replaceable>address_match_list</replaceable> }; </optional>
+ <optional> allow-transfer { <replaceable>address_match_list</replaceable> }; </optional>
+ <optional> allow-update { <replaceable>address_match_list</replaceable> }; </optional>
+ <optional> update-check-ksk <replaceable>yes_or_no</replaceable>; </optional>
+ <optional> dnssec-dnskey-kskonly <replaceable>yes_or_no</replaceable>; </optional>
+ <optional> dnssec-loadkeys-interval <replaceable>number</replaceable>; </optional>
+ <optional> update-policy <replaceable>local</replaceable> | { <replaceable>update_policy_rule</replaceable> <optional>...</optional> }; </optional>
+ <optional> also-notify { <replaceable>ip_addr</replaceable> <optional>port <replaceable>ip_port</replaceable></optional> <optional>dscp <replaceable>ip_dscp</replaceable></optional> ;
+ <optional> <replaceable>ip_addr</replaceable> <optional>port <replaceable>ip_port</replaceable></optional> <optional>dscp <replaceable>ip_dscp</replaceable></optional> ; ... </optional> }; </optional>
+ <optional> check-names (<constant>warn</constant>|<constant>fail</constant>|<constant>ignore</constant>) ; </optional>
+ <optional> check-mx (<constant>warn</constant>|<constant>fail</constant>|<constant>ignore</constant>) ; </optional>
+ <optional> check-wildcard <replaceable>yes_or_no</replaceable>; </optional>
+ <optional> check-spf ( <replaceable>warn</replaceable> | <replaceable>fail</replaceable> | <replaceable>ignore</replaceable> ); </optional>
+ <optional> check-integrity <replaceable>yes_or_no</replaceable> ; </optional>
+ <optional> dialup <replaceable>dialup_option</replaceable> ; </optional>
+ <optional> file <replaceable>string</replaceable> ; </optional>
+ <optional> masterfile-format (<constant>text</constant>|<constant>raw</constant>|<constant>map</constant>) ; </optional>
+ <optional> journal <replaceable>string</replaceable> ; </optional>
+ <optional> max-journal-size <replaceable>size_spec</replaceable>; </optional>
+ <optional> forward (<constant>only</constant>|<constant>first</constant>) ; </optional>
+ <optional> forwarders { <optional> <replaceable>ip_addr</replaceable> <optional>port <replaceable>ip_port</replaceable></optional> <optional>dscp <replaceable>ip_dscp</replaceable></optional> ; ... </optional> }; </optional>
+ <optional> ixfr-base <replaceable>string</replaceable> ; </optional>
+ <optional> ixfr-from-differences <replaceable>yes_or_no</replaceable>; </optional>
+ <optional> ixfr-tmp-file <replaceable>string</replaceable> ; </optional>
+ <optional> request-ixfr <replaceable>yes_or_no</replaceable> ; </optional>
+ <optional> maintain-ixfr-base <replaceable>yes_or_no</replaceable> ; </optional>
+ <optional> max-ixfr-log-size <replaceable>number</replaceable> ; </optional>
+ <optional> max-transfer-idle-out <replaceable>number</replaceable> ; </optional>
+ <optional> max-transfer-time-out <replaceable>number</replaceable> ; </optional>
+ <optional> notify <replaceable>yes_or_no</replaceable> | <replaceable>explicit</replaceable> | <replaceable>master-only</replaceable> ; </optional>
+ <optional> notify-delay <replaceable>seconds</replaceable> ; </optional>
+ <optional> notify-to-soa <replaceable>yes_or_no</replaceable>; </optional>
+ <optional> pubkey <replaceable>number</replaceable> <replaceable>number</replaceable> <replaceable>number</replaceable> <replaceable>string</replaceable> ; </optional>
+ <optional> notify-source (<replaceable>ip4_addr</replaceable> | <constant>*</constant>) <optional>port <replaceable>ip_port</replaceable></optional> <optional>dscp <replaceable>ip_dscp</replaceable></optional> ; </optional>
+ <optional> notify-source-v6 (<replaceable>ip6_addr</replaceable> | <constant>*</constant>) <optional>port <replaceable>ip_port</replaceable></optional> <optional>dscp <replaceable>ip_dscp</replaceable></optional> ; </optional>
+ <optional> zone-statistics <replaceable>full</replaceable> | <replaceable>terse</replaceable> | <replaceable>none</replaceable>; </optional>
+ <optional> sig-validity-interval <replaceable>number</replaceable> <optional><replaceable>number</replaceable></optional> ; </optional>
+ <optional> sig-signing-nodes <replaceable>number</replaceable> ; </optional>
+ <optional> sig-signing-signatures <replaceable>number</replaceable> ; </optional>
+ <optional> sig-signing-type <replaceable>number</replaceable> ; </optional>
+ <optional> database <replaceable>string</replaceable> ; </optional>
+ <optional> min-refresh-time <replaceable>number</replaceable> ; </optional>
+ <optional> max-refresh-time <replaceable>number</replaceable> ; </optional>
+ <optional> min-retry-time <replaceable>number</replaceable> ; </optional>
+ <optional> max-retry-time <replaceable>number</replaceable> ; </optional>
+ <optional> key-directory <replaceable>path_name</replaceable>; </optional>
+ <optional> auto-dnssec <constant>allow</constant>|<constant>maintain</constant>|<constant>off</constant>; </optional>
+ <optional> inline-signing <replaceable>yes_or_no</replaceable>; </optional>
+ <optional> zero-no-soa-ttl <replaceable>yes_or_no</replaceable> ; </optional>
+ <optional> serial-update-method <constant>increment</constant>|<constant>unixtime</constant>; </optional>
+};
+
+zone <replaceable>zone_name</replaceable> <optional><replaceable>class</replaceable></optional> {
+ type slave;
+ <optional> allow-notify { <replaceable>address_match_list</replaceable> }; </optional>
+ <optional> allow-query { <replaceable>address_match_list</replaceable> }; </optional>
+ <optional> allow-query-on { <replaceable>address_match_list</replaceable> }; </optional>
+ <optional> allow-transfer { <replaceable>address_match_list</replaceable> }; </optional>
+ <optional> allow-update-forwarding { <replaceable>address_match_list</replaceable> }; </optional>
+ <optional> dnssec-update-mode ( <replaceable>maintain</replaceable> | <replaceable>no-resign</replaceable> ); </optional>
+ <optional> update-check-ksk <replaceable>yes_or_no</replaceable>; </optional>
+ <optional> dnssec-dnskey-kskonly <replaceable>yes_or_no</replaceable>; </optional>
+ <optional> dnssec-loadkeys-interval <replaceable>number</replaceable>; </optional>
+ <optional> dnssec-secure-to-insecure <replaceable>yes_or_no</replaceable> ; </optional>
+ <optional> try-tcp-refresh <replaceable>yes_or_no</replaceable>; </optional>
+ <optional> also-notify <optional>port <replaceable>ip_port</replaceable></optional> <optional>dscp <replaceable>ip_dscp</replaceable></optional> { ( <replaceable>masters_list</replaceable> | <replaceable>ip_addr</replaceable>
+ <optional>port <replaceable>ip_port</replaceable></optional>
+ <optional>dscp <replaceable>ip_dscp</replaceable></optional>
+ <optional>key <replaceable>key</replaceable></optional> ) ; <optional>...</optional> }; </optional>
+ <optional> check-names (<constant>warn</constant>|<constant>fail</constant>|<constant>ignore</constant>) ; </optional>
+ <optional> dialup <replaceable>dialup_option</replaceable> ; </optional>
+ <optional> file <replaceable>string</replaceable> ; </optional>
+ <optional> masterfile-format (<constant>text</constant>|<constant>raw</constant>|<constant>map</constant>) ; </optional>
+ <optional> journal <replaceable>string</replaceable> ; </optional>
+ <optional> max-journal-size <replaceable>size_spec</replaceable>; </optional>
+ <optional> forward (<constant>only</constant>|<constant>first</constant>) ; </optional>
+ <optional> forwarders { <optional> <replaceable>ip_addr</replaceable> <optional>port <replaceable>ip_port</replaceable></optional> <optional>dscp <replaceable>ip_dscp</replaceable></optional> ; ... </optional> }; </optional>
+ <optional> ixfr-base <replaceable>string</replaceable> ; </optional>
+ <optional> ixfr-from-differences <replaceable>yes_or_no</replaceable>; </optional>
+ <optional> ixfr-tmp-file <replaceable>string</replaceable> ; </optional>
+ <optional> maintain-ixfr-base <replaceable>yes_or_no</replaceable> ; </optional>
+ <optional> masters <optional>port <replaceable>ip_port</replaceable></optional> <optional>dscp <replaceable>ip_dscp</replaceable></optional> { ( <replaceable>masters_list</replaceable> | <replaceable>ip_addr</replaceable>
+ <optional>port <replaceable>ip_port</replaceable></optional>
+ <optional>dscp <replaceable>ip_dscp</replaceable></optional>
+ <optional>key <replaceable>key</replaceable></optional> ) ; <optional>...</optional> }; </optional>
+ <optional> max-ixfr-log-size <replaceable>number</replaceable> ; </optional>
+ <optional> max-transfer-idle-in <replaceable>number</replaceable> ; </optional>
+ <optional> max-transfer-idle-out <replaceable>number</replaceable> ; </optional>
+ <optional> max-transfer-time-in <replaceable>number</replaceable> ; </optional>
+ <optional> max-transfer-time-out <replaceable>number</replaceable> ; </optional>
+ <optional> notify <replaceable>yes_or_no</replaceable> | <replaceable>explicit</replaceable> | <replaceable>master-only</replaceable> ; </optional>
+ <optional> notify-delay <replaceable>seconds</replaceable> ; </optional>
+ <optional> notify-to-soa <replaceable>yes_or_no</replaceable>; </optional>
+ <optional> pubkey <replaceable>number</replaceable> <replaceable>number</replaceable> <replaceable>number</replaceable> <replaceable>string</replaceable> ; </optional>
+ <optional> transfer-source (<replaceable>ip4_addr</replaceable> | <constant>*</constant>) <optional>port <replaceable>ip_port</replaceable></optional> <optional>dscp <replaceable>ip_dscp</replaceable></optional> ; </optional>
+ <optional> transfer-source-v6 (<replaceable>ip6_addr</replaceable> | <constant>*</constant>) <optional>port <replaceable>ip_port</replaceable></optional> <optional>dscp <replaceable>ip_dscp</replaceable></optional> ; </optional>
+ <optional> alt-transfer-source (<replaceable>ip4_addr</replaceable> | <constant>*</constant>) <optional>port <replaceable>ip_port</replaceable></optional> <optional>dscp <replaceable>ip_dscp</replaceable></optional> ; </optional>
+ <optional> alt-transfer-source-v6 (<replaceable>ip6_addr</replaceable> | <constant>*</constant>)
+ <optional>port <replaceable>ip_port</replaceable></optional>
+ <optional>dscp <replaceable>ip_dscp</replaceable></optional> ; </optional>
+ <optional> use-alt-transfer-source <replaceable>yes_or_no</replaceable>; </optional>
+ <optional> notify-source (<replaceable>ip4_addr</replaceable> | <constant>*</constant>) <optional>port <replaceable>ip_port</replaceable></optional> <optional>dscp <replaceable>ip_dscp</replaceable></optional> ; </optional>
+ <optional> notify-source-v6 (<replaceable>ip6_addr</replaceable> | <constant>*</constant>) <optional>port <replaceable>ip_port</replaceable></optional> <optional>dscp <replaceable>ip_dscp</replaceable></optional> ; </optional>
+ <optional> zone-statistics <replaceable>full</replaceable> | <replaceable>terse</replaceable> | <replaceable>none</replaceable>; </optional>
+ <optional> sig-validity-interval <replaceable>number</replaceable> <optional><replaceable>number</replaceable></optional> ; </optional>
+ <optional> sig-signing-nodes <replaceable>number</replaceable> ; </optional>
+ <optional> sig-signing-signatures <replaceable>number</replaceable> ; </optional>
+ <optional> sig-signing-type <replaceable>number</replaceable> ; </optional>
+ <optional> database <replaceable>string</replaceable> ; </optional>
+ <optional> min-refresh-time <replaceable>number</replaceable> ; </optional>
+ <optional> max-refresh-time <replaceable>number</replaceable> ; </optional>
+ <optional> min-retry-time <replaceable>number</replaceable> ; </optional>
+ <optional> max-retry-time <replaceable>number</replaceable> ; </optional>
+ <optional> key-directory <replaceable>path_name</replaceable>; </optional>
+ <optional> auto-dnssec <constant>allow</constant>|<constant>maintain</constant>|<constant>off</constant>; </optional>
+ <optional> inline-signing <replaceable>yes_or_no</replaceable>; </optional>
+ <optional> multi-master <replaceable>yes_or_no</replaceable> ; </optional>
+ <optional> zero-no-soa-ttl <replaceable>yes_or_no</replaceable> ; </optional>
+};
+
+zone <replaceable>zone_name</replaceable> <optional><replaceable>class</replaceable></optional> {
+ type hint;
+ file <replaceable>string</replaceable> ;
+ <optional> delegation-only <replaceable>yes_or_no</replaceable> ; </optional>
+ <optional> check-names (<constant>warn</constant>|<constant>fail</constant>|<constant>ignore</constant>) ; </optional> // Not Implemented.
+};
+
+zone <replaceable>zone_name</replaceable> <optional><replaceable>class</replaceable></optional> {
+ type stub;
+ <optional> allow-query { <replaceable>address_match_list</replaceable> }; </optional>
+ <optional> allow-query-on { <replaceable>address_match_list</replaceable> }; </optional>
+ <optional> check-names (<constant>warn</constant>|<constant>fail</constant>|<constant>ignore</constant>) ; </optional>
+ <optional> dialup <replaceable>dialup_option</replaceable> ; </optional>
+ <optional> delegation-only <replaceable>yes_or_no</replaceable> ; </optional>
+ <optional> file <replaceable>string</replaceable> ; </optional>
+ <optional> masterfile-format (<constant>text</constant>|<constant>raw</constant>|<constant>map</constant>) ; </optional>
+ <optional> forward (<constant>only</constant>|<constant>first</constant>) ; </optional>
+ <optional> forwarders { <optional> <replaceable>ip_addr</replaceable> <optional>port <replaceable>ip_port</replaceable></optional> <optional>dscp <replaceable>ip_dscp</replaceable></optional> ; ... </optional> }; </optional>
+ <optional> masters <optional>port <replaceable>ip_port</replaceable></optional> <optional>dscp <replaceable>ip_dscp</replaceable></optional> { ( <replaceable>masters_list</replaceable> | <replaceable>ip_addr</replaceable>
+ <optional>port <replaceable>ip_port</replaceable></optional>
+ <optional>dscp <replaceable>ip_dscp</replaceable></optional>
+ <optional>key <replaceable>key</replaceable></optional> ) ; <optional>...</optional> }; </optional>
+ <optional> max-transfer-idle-in <replaceable>number</replaceable> ; </optional>
+ <optional> max-transfer-time-in <replaceable>number</replaceable> ; </optional>
+ <optional> pubkey <replaceable>number</replaceable> <replaceable>number</replaceable> <replaceable>number</replaceable> <replaceable>string</replaceable> ; </optional>
+ <optional> transfer-source (<replaceable>ip4_addr</replaceable> | <constant>*</constant>) <optional>port <replaceable>ip_port</replaceable></optional> <optional>dscp <replaceable>ip_dscp</replaceable></optional> ; </optional>
+ <optional> transfer-source-v6 (<replaceable>ip6_addr</replaceable> | <constant>*</constant>)
+ <optional>port <replaceable>ip_port</replaceable></optional> <optional>dscp <replaceable>ip_dscp</replaceable></optional> ; </optional>
+ <optional> alt-transfer-source (<replaceable>ip4_addr</replaceable> | <constant>*</constant>) <optional>port <replaceable>ip_port</replaceable></optional> <optional>dscp <replaceable>ip_dscp</replaceable></optional> ; </optional>
+ <optional> alt-transfer-source-v6 (<replaceable>ip6_addr</replaceable> | <constant>*</constant>)
+ <optional>port <replaceable>ip_port</replaceable></optional> <optional>dscp <replaceable>ip_dscp</replaceable></optional> ; </optional>
+ <optional> use-alt-transfer-source <replaceable>yes_or_no</replaceable>; </optional>
+ <optional> zone-statistics <replaceable>yes_or_no</replaceable> ; </optional>
+ <optional> database <replaceable>string</replaceable> ; </optional>
+ <optional> min-refresh-time <replaceable>number</replaceable> ; </optional>
+ <optional> max-refresh-time <replaceable>number</replaceable> ; </optional>
+ <optional> min-retry-time <replaceable>number</replaceable> ; </optional>
+ <optional> max-retry-time <replaceable>number</replaceable> ; </optional>
+ <optional> multi-master <replaceable>yes_or_no</replaceable> ; </optional>
+};
+
+zone <replaceable>zone_name</replaceable> <optional><replaceable>class</replaceable></optional> {
+ type static-stub;
+ <optional> allow-query { <replaceable>address_match_list</replaceable> }; </optional>
+ <optional> server-addresses { <optional> <replaceable>ip_addr</replaceable> ; ... </optional> }; </optional>
+ <optional> server-names { <optional> <replaceable>namelist</replaceable> </optional> }; </optional>
+ <optional> zone-statistics <replaceable>yes_or_no</replaceable> ; </optional>
+};
+
+zone <replaceable>zone_name</replaceable> <optional><replaceable>class</replaceable></optional> {
+ type forward;
+ <optional> forward (<constant>only</constant>|<constant>first</constant>) ; </optional>
+ <optional> forwarders { <optional> <replaceable>ip_addr</replaceable> <optional>port <replaceable>ip_port</replaceable></optional> <optional>dscp <replaceable>ip_dscp</replaceable></optional> ; ... </optional> }; </optional>
+ <optional> delegation-only <replaceable>yes_or_no</replaceable> ; </optional>
+};
+
+zone <replaceable>"."</replaceable> <optional><replaceable>class</replaceable></optional> {
+ type redirect;
+ file <replaceable>string</replaceable> ;
+ <optional> masterfile-format (<constant>text</constant>|<constant>raw</constant>|<constant>map</constant>) ; </optional>
+ <optional> allow-query { <replaceable>address_match_list</replaceable> }; </optional>
+};
+
+zone <replaceable>zone_name</replaceable> <optional><replaceable>class</replaceable></optional> {
+ type delegation-only;
+};
+
+zone <replaceable>zone_name</replaceable> <optional><replaceable>class</replaceable></optional> {
+ <optional> in-view <replaceable>string</replaceable> ; </optional>
+};
+
+</programlisting>
+
+ </sect2>
+ <sect2>
+ <title><command>zone</command> Statement Definition and Usage</title>
+ <sect3>
+ <title>Zone Types</title>
+ <informaltable colsep="0" rowsep="0">
+ <tgroup cols="2" colsep="0" rowsep="0" tgroupstyle="3Level-table">
+ <!--colspec colname="1" colnum="1" colsep="0" colwidth="1.108in"/-->
+ <!--colspec colname="2" colnum="2" colsep="0" colwidth="4.017in"/-->
+ <colspec colname="1" colnum="1" colsep="0"/>
+ <colspec colname="2" colnum="2" colsep="0" colwidth="4.017in"/>
+ <tbody>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ <varname>master</varname>
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ The server has a master copy of the data
+ for the zone and will be able to provide authoritative
+ answers for
+ it.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ <varname>slave</varname>
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ A slave zone is a replica of a master
+ zone. The <command>masters</command> list
+ specifies one or more IP addresses
+ of master servers that the slave contacts to update
+ its copy of the zone.
+ Masters list elements can also be names of other
+ masters lists.
+ By default, transfers are made from port 53 on the
+ servers; this can
+ be changed for all servers by specifying a port number
+ before the
+ list of IP addresses, or on a per-server basis after
+ the IP address.
+ Authentication to the master can also be done with
+ per-server TSIG keys.
+ If a file is specified, then the
+ replica will be written to this file whenever the zone
+ is changed,
+ and reloaded from this file on a server restart. Use
+ of a file is
+ recommended, since it often speeds server startup and
+ eliminates
+ a needless waste of bandwidth. Note that for large
+ numbers (in the
+ tens or hundreds of thousands) of zones per server, it
+ is best to
+ use a two-level naming scheme for zone filenames. For
+ example,
+ a slave server for the zone <literal>example.com</literal> might place
+ the zone contents into a file called
+ <filename>ex/example.com</filename> where <filename>ex/</filename> is
+ just the first two letters of the zone name. (Most
+ operating systems
+ behave very slowly if you put 100000 files into
+ a single directory.)
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ <varname>stub</varname>
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ A stub zone is similar to a slave zone,
+ except that it replicates only the NS records of a
+ master zone instead
+ of the entire zone. Stub zones are not a standard part
+ of the DNS;
+ they are a feature specific to the <acronym>BIND</acronym> implementation.
+ </para>
+
+ <para>
+ Stub zones can be used to eliminate the need for glue
+ NS record
+ in a parent zone at the expense of maintaining a stub
+ zone entry and
+ a set of name server addresses in <filename>named.conf</filename>.
+ This usage is not recommended for new configurations,
+ and BIND 9
+ supports it only in a limited way.
+ In <acronym>BIND</acronym> 4/8, zone
+ transfers of a parent zone
+ included the NS records from stub children of that
+ zone. This meant
+ that, in some cases, users could get away with
+ configuring child stubs
+ only in the master server for the parent zone. <acronym>BIND</acronym>
+ 9 never mixes together zone data from different zones
+ in this
+ way. Therefore, if a <acronym>BIND</acronym> 9 master serving a parent
+ zone has child stub zones configured, all the slave
+ servers for the
+ parent zone also need to have the same child stub
+ zones
+ configured.
+ </para>
+
+ <para>
+ Stub zones can also be used as a way of forcing the
+ resolution
+ of a given domain to use a particular set of
+ authoritative servers.
+ For example, the caching name servers on a private
+ network using
+ RFC1918 addressing may be configured with stub zones
+ for
+ <literal>10.in-addr.arpa</literal>
+ to use a set of internal name servers as the
+ authoritative
+ servers for that domain.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ <varname>static-stub</varname>
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ A static-stub zone is similar to a stub zone
+ with the following exceptions:
+ the zone data is statically configured, rather
+ than transferred from a master server;
+ when recursion is necessary for a query that
+ matches a static-stub zone, the locally
+ configured data (nameserver names and glue addresses)
+ is always used even if different authoritative
+ information is cached.
+ </para>
+ <para>
+ Zone data is configured via the
+ <command>server-addresses</command> and
+ <command>server-names</command> zone options.
+ </para>
+ <para>
+ The zone data is maintained in the form of NS
+ and (if necessary) glue A or AAAA RRs
+ internally, which can be seen by dumping zone
+ databases by <command>rndc dumpdb -all</command>.
+ The configured RRs are considered local configuration
+ parameters rather than public data.
+ Non recursive queries (i.e., those with the RD
+ bit off) to a static-stub zone are therefore
+ prohibited and will be responded with REFUSED.
+ </para>
+ <para>
+ Since the data is statically configured, no
+ zone maintenance action takes place for a static-stub
+ zone.
+ For example, there is no periodic refresh
+ attempt, and an incoming notify message
+ will be rejected with an rcode of NOTAUTH.
+ </para>
+ <para>
+ Each static-stub zone is configured with
+ internally generated NS and (if necessary)
+ glue A or AAAA RRs
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ <varname>forward</varname>
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ A "forward zone" is a way to configure
+ forwarding on a per-domain basis. A <command>zone</command> statement
+ of type <command>forward</command> can
+ contain a <command>forward</command>
+ and/or <command>forwarders</command>
+ statement,
+ which will apply to queries within the domain given by
+ the zone
+ name. If no <command>forwarders</command>
+ statement is present or
+ an empty list for <command>forwarders</command> is given, then no
+ forwarding will be done for the domain, canceling the
+ effects of
+ any forwarders in the <command>options</command> statement. Thus
+ if you want to use this type of zone to change the
+ behavior of the
+ global <command>forward</command> option
+ (that is, "forward first"
+ to, then "forward only", or vice versa, but want to
+ use the same
+ servers as set globally) you need to re-specify the
+ global forwarders.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ <varname>hint</varname>
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ The initial set of root name servers is
+ specified using a "hint zone". When the server starts
+ up, it uses
+ the root hints to find a root name server and get the
+ most recent
+ list of root name servers. If no hint zone is
+ specified for class
+ IN, the server uses a compiled-in default set of root
+ servers hints.
+ Classes other than IN have no built-in defaults hints.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ <varname>redirect</varname>
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ Redirect zones are used to provide answers to
+ queries when normal resolution would result in
+ NXDOMAIN being returned.
+ Only one redirect zone is supported
+ per view. <command>allow-query</command> can be
+ used to restrict which clients see these answers.
+ </para>
+ <para>
+ If the client has requested DNSSEC records (DO=1) and
+ the NXDOMAIN response is signed then no substitution
+ will occur.
+ </para>
+ <para>
+ To redirect all NXDOMAIN responses to
+ 100.100.100.2 and
+ 2001:ffff:ffff::100.100.100.2, one would
+ configure a type redirect zone named ".",
+ with the zone file containing wildcard records
+ that point to the desired addresses:
+ <literal>"*. IN A 100.100.100.2"</literal>
+ and
+ <literal>"*. IN AAAA 2001:ffff:ffff::100.100.100.2"</literal>.
+ </para>
+ <para>
+ To redirect all Spanish names (under .ES) one
+ would use similar entries but with the names
+ "*.ES." instead of "*.". To redirect all
+ commercial Spanish names (under COM.ES) one
+ would use wildcard entries called "*.COM.ES.".
+ </para>
+ <para>
+ Note that the redirect zone supports all
+ possible types; it is not limited to A and
+ AAAA records.
+ </para>
+ <para>
+ Because redirect zones are not referenced
+ directly by name, they are not kept in the
+ zone lookup table with normal master and slave
+ zones. Consequently, it is not currently possible
+ to use
+ <command>rndc reload
+ <replaceable>zonename</replaceable></command>
+ to reload a redirect zone. However, when using
+ <command>rndc reload</command> without specifying
+ a zone name, redirect zones will be reloaded along
+ with other zones.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ <varname>delegation-only</varname>
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ This is used to enforce the delegation-only
+ status of infrastructure zones (e.g. COM,
+ NET, ORG). Any answer that is received
+ without an explicit or implicit delegation
+ in the authority section will be treated
+ as NXDOMAIN. This does not apply to the
+ zone apex. This should not be applied to
+ leaf zones.
+ </para>
+ <para>
+ <varname>delegation-only</varname> has no
+ effect on answers received from forwarders.
+ </para>
+ <para>
+ See caveats in <xref linkend="root_delegation_only"/>.
+ </para>
+ </entry>
+ </row>
+ </tbody>
+ </tgroup>
+ </informaltable>
+ </sect3>
+
+ <sect3>
+ <title>Class</title>
+ <para>
+ The zone's name may optionally be followed by a class. If
+ a class is not specified, class <literal>IN</literal> (for <varname>Internet</varname>),
+ is assumed. This is correct for the vast majority of cases.
+ </para>
+ <para>
+ The <literal>hesiod</literal> class is
+ named for an information service from MIT's Project Athena. It
+ is
+ used to share information about various systems databases, such
+ as users, groups, printers and so on. The keyword
+ <literal>HS</literal> is
+ a synonym for hesiod.
+ </para>
+ <para>
+ Another MIT development is Chaosnet, a LAN protocol created
+ in the mid-1970s. Zone data for it can be specified with the <literal>CHAOS</literal> class.
+ </para>
+ </sect3>
+
+ <sect3>
+ <title>Zone Options</title>
+
+ <variablelist>
+
+ <varlistentry>
+ <term><command>allow-notify</command></term>
+ <listitem>
+ <para>
+ See the description of
+ <command>allow-notify</command> in <xref linkend="access_control"/>.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>allow-query</command></term>
+ <listitem>
+ <para>
+ See the description of
+ <command>allow-query</command> in <xref linkend="access_control"/>.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>allow-query-on</command></term>
+ <listitem>
+ <para>
+ See the description of
+ <command>allow-query-on</command> in <xref linkend="access_control"/>.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>allow-transfer</command></term>
+ <listitem>
+ <para>
+ See the description of <command>allow-transfer</command>
+ in <xref linkend="access_control"/>.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>allow-update</command></term>
+ <listitem>
+ <para>
+ See the description of <command>allow-update</command>
+ in <xref linkend="access_control"/>.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>update-policy</command></term>
+ <listitem>
+ <para>
+ Specifies a "Simple Secure Update" policy. See
+ <xref linkend="dynamic_update_policies"/>.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>allow-update-forwarding</command></term>
+ <listitem>
+ <para>
+ See the description of <command>allow-update-forwarding</command>
+ in <xref linkend="access_control"/>.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>also-notify</command></term>
+ <listitem>
+ <para>
+ Only meaningful if <command>notify</command>
+ is
+ active for this zone. The set of machines that will
+ receive a
+ <literal>DNS NOTIFY</literal> message
+ for this zone is made up of all the listed name servers
+ (other than
+ the primary master) for the zone plus any IP addresses
+ specified
+ with <command>also-notify</command>. A port
+ may be specified
+ with each <command>also-notify</command>
+ address to send the notify
+ messages to a port other than the default of 53.
+ A TSIG key may also be specified to cause the
+ <literal>NOTIFY</literal> to be signed by the
+ given key.
+ <command>also-notify</command> is not
+ meaningful for stub zones.
+ The default is the empty list.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>check-names</command></term>
+ <listitem>
+ <para>
+ This option is used to restrict the character set and
+ syntax of
+ certain domain names in master files and/or DNS responses
+ received from the
+ network. The default varies according to zone type. For <command>master</command> zones the default is <command>fail</command>. For <command>slave</command>
+ zones the default is <command>warn</command>.
+ It is not implemented for <command>hint</command> zones.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>check-mx</command></term>
+ <listitem>
+ <para>
+ See the description of
+ <command>check-mx</command> in <xref linkend="boolean_options"/>.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>check-spf</command></term>
+ <listitem>
+ <para>
+ See the description of
+ <command>check-spf</command> in <xref linkend="boolean_options"/>.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>check-wildcard</command></term>
+ <listitem>
+ <para>
+ See the description of
+ <command>check-wildcard</command> in <xref linkend="boolean_options"/>.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>check-integrity</command></term>
+ <listitem>
+ <para>
+ See the description of
+ <command>check-integrity</command> in <xref linkend="boolean_options"/>.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>check-sibling</command></term>
+ <listitem>
+ <para>
+ See the description of
+ <command>check-sibling</command> in <xref linkend="boolean_options"/>.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>zero-no-soa-ttl</command></term>
+ <listitem>
+ <para>
+ See the description of
+ <command>zero-no-soa-ttl</command> in <xref linkend="boolean_options"/>.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>update-check-ksk</command></term>
+ <listitem>
+ <para>
+ See the description of
+ <command>update-check-ksk</command> in <xref linkend="boolean_options"/>.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>dnssec-update-mode</command></term>
+ <listitem>
+ <para>
+ See the description of
+ <command>dnssec-update-mode</command> in <xref linkend="options"/>.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>dnssec-dnskey-kskonly</command></term>
+ <listitem>
+ <para>
+ See the description of
+ <command>dnssec-dnskey-kskonly</command> in <xref linkend="boolean_options"/>.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>try-tcp-refresh</command></term>
+ <listitem>
+ <para>
+ See the description of
+ <command>try-tcp-refresh</command> in <xref linkend="boolean_options"/>.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>database</command></term>
+ <listitem>
+ <para>
+ Specify the type of database to be used for storing the
+ zone data. The string following the <command>database</command> keyword
+ is interpreted as a list of whitespace-delimited words.
+ The first word
+ identifies the database type, and any subsequent words are
+ passed
+ as arguments to the database to be interpreted in a way
+ specific
+ to the database type.
+ </para>
+ <para>
+ The default is <userinput>"rbt"</userinput>, BIND 9's
+ native in-memory
+ red-black-tree database. This database does not take
+ arguments.
+ </para>
+ <para>
+ Other values are possible if additional database drivers
+ have been linked into the server. Some sample drivers are
+ included
+ with the distribution but none are linked in by default.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>dialup</command></term>
+ <listitem>
+ <para>
+ See the description of
+ <command>dialup</command> in <xref linkend="boolean_options"/>.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>delegation-only</command></term>
+ <listitem>
+ <para>
+ The flag only applies to hint and stub zones. If set
+ to <userinput>yes</userinput>, then the zone will also be
+ treated as if it is also a delegation-only type zone.
+ </para>
+ <para>
+ See caveats in <xref linkend="root_delegation_only"/>.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>forward</command></term>
+ <listitem>
+ <para>
+ Only meaningful if the zone has a forwarders
+ list. The <command>only</command> value causes
+ the lookup to fail
+ after trying the forwarders and getting no answer, while <command>first</command> would
+ allow a normal lookup to be tried.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>forwarders</command></term>
+ <listitem>
+ <para>
+ Used to override the list of global forwarders.
+ If it is not specified in a zone of type <command>forward</command>,
+ no forwarding is done for the zone and the global options are
+ not used.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>ixfr-base</command></term>
+ <listitem>
+ <para>
+ Was used in <acronym>BIND</acronym> 8 to
+ specify the name
+ of the transaction log (journal) file for dynamic update
+ and IXFR.
+ <acronym>BIND</acronym> 9 ignores the option
+ and constructs the name of the journal
+ file by appending "<filename>.jnl</filename>"
+ to the name of the
+ zone file.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>ixfr-tmp-file</command></term>
+ <listitem>
+ <para>
+ Was an undocumented option in <acronym>BIND</acronym> 8.
+ Ignored in <acronym>BIND</acronym> 9.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>journal</command></term>
+ <listitem>
+ <para>
+ Allow the default journal's filename to be overridden.
+ The default is the zone's filename with "<filename>.jnl</filename>" appended.
+ This is applicable to <command>master</command> and <command>slave</command> zones.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>max-journal-size</command></term>
+ <listitem>
+ <para>
+ See the description of
+ <command>max-journal-size</command> in <xref linkend="server_resource_limits"/>.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>max-transfer-time-in</command></term>
+ <listitem>
+ <para>
+ See the description of
+ <command>max-transfer-time-in</command> in <xref linkend="zone_transfers"/>.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>max-transfer-idle-in</command></term>
+ <listitem>
+ <para>
+ See the description of
+ <command>max-transfer-idle-in</command> in <xref linkend="zone_transfers"/>.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>max-transfer-time-out</command></term>
+ <listitem>
+ <para>
+ See the description of
+ <command>max-transfer-time-out</command> in <xref linkend="zone_transfers"/>.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>max-transfer-idle-out</command></term>
+ <listitem>
+ <para>
+ See the description of
+ <command>max-transfer-idle-out</command> in <xref linkend="zone_transfers"/>.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>notify</command></term>
+ <listitem>
+ <para>
+ See the description of
+ <command>notify</command> in <xref linkend="boolean_options"/>.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>notify-delay</command></term>
+ <listitem>
+ <para>
+ See the description of
+ <command>notify-delay</command> in <xref linkend="tuning"/>.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>notify-to-soa</command></term>
+ <listitem>
+ <para>
+ See the description of
+ <command>notify-to-soa</command> in
+ <xref linkend="boolean_options"/>.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>pubkey</command></term>
+ <listitem>
+ <para>
+ In <acronym>BIND</acronym> 8, this option was
+ intended for specifying
+ a public zone key for verification of signatures in DNSSEC
+ signed
+ zones when they are loaded from disk. <acronym>BIND</acronym> 9 does not verify signatures
+ on load and ignores the option.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>zone-statistics</command></term>
+ <listitem>
+ <para>
+ If <userinput>yes</userinput>, the server will keep
+ statistical
+ information for this zone, which can be dumped to the
+ <command>statistics-file</command> defined in
+ the server options.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>server-addresses</command></term>
+ <listitem>
+ <para>
+ Only meaningful for static-stub zones.
+ This is a list of IP addresses to which queries
+ should be sent in recursive resolution for the
+ zone.
+ A non empty list for this option will internally
+ configure the apex NS RR with associated glue A or
+ AAAA RRs.
+ </para>
+ <para>
+ For example, if "example.com" is configured as a
+ static-stub zone with 192.0.2.1 and 2001:db8::1234
+ in a <command>server-addresses</command> option,
+ the following RRs will be internally configured.
+ </para>
+<programlisting>example.com. NS example.com.
+example.com. A 192.0.2.1
+example.com. AAAA 2001:db8::1234</programlisting>
+ <para>
+ These records are internally used to resolve
+ names under the static-stub zone.
+ For instance, if the server receives a query for
+ "www.example.com" with the RD bit on, the server
+ will initiate recursive resolution and send
+ queries to 192.0.2.1 and/or 2001:db8::1234.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>server-names</command></term>
+ <listitem>
+ <para>
+ Only meaningful for static-stub zones.
+ This is a list of domain names of nameservers that
+ act as authoritative servers of the static-stub
+ zone.
+ These names will be resolved to IP addresses when
+ <command>named</command> needs to send queries to
+ these servers.
+ To make this supplemental resolution successful,
+ these names must not be a subdomain of the origin
+ name of static-stub zone.
+ That is, when "example.net" is the origin of a
+ static-stub zone, "ns.example" and
+ "master.example.com" can be specified in the
+ <command>server-names</command> option, but
+ "ns.example.net" cannot, and will be rejected by
+ the configuration parser.
+ </para>
+ <para>
+ A non empty list for this option will internally
+ configure the apex NS RR with the specified names.
+ For example, if "example.com" is configured as a
+ static-stub zone with "ns1.example.net" and
+ "ns2.example.net"
+ in a <command>server-names</command> option,
+ the following RRs will be internally configured.
+ </para>
+<programlisting>example.com. NS ns1.example.net.
+example.com. NS ns2.example.net.
+</programlisting>
+ <para>
+ These records are internally used to resolve
+ names under the static-stub zone.
+ For instance, if the server receives a query for
+ "www.example.com" with the RD bit on, the server
+ initiate recursive resolution,
+ resolve "ns1.example.net" and/or
+ "ns2.example.net" to IP addresses, and then send
+ queries to (one or more of) these addresses.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>sig-validity-interval</command></term>
+ <listitem>
+ <para>
+ See the description of
+ <command>sig-validity-interval</command> in <xref linkend="tuning"/>.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>sig-signing-nodes</command></term>
+ <listitem>
+ <para>
+ See the description of
+ <command>sig-signing-nodes</command> in <xref linkend="tuning"/>.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>sig-signing-signatures</command></term>
+ <listitem>
+ <para>
+ See the description of
+ <command>sig-signing-signatures</command> in <xref linkend="tuning"/>.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>sig-signing-type</command></term>
+ <listitem>
+ <para>
+ See the description of
+ <command>sig-signing-type</command> in <xref linkend="tuning"/>.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>transfer-source</command></term>
+ <listitem>
+ <para>
+ See the description of
+ <command>transfer-source</command> in <xref linkend="zone_transfers"/>.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>transfer-source-v6</command></term>
+ <listitem>
+ <para>
+ See the description of
+ <command>transfer-source-v6</command> in <xref linkend="zone_transfers"/>.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>alt-transfer-source</command></term>
+ <listitem>
+ <para>
+ See the description of
+ <command>alt-transfer-source</command> in <xref linkend="zone_transfers"/>.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>alt-transfer-source-v6</command></term>
+ <listitem>
+ <para>
+ See the description of
+ <command>alt-transfer-source-v6</command> in <xref linkend="zone_transfers"/>.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>use-alt-transfer-source</command></term>
+ <listitem>
+ <para>
+ See the description of
+ <command>use-alt-transfer-source</command> in <xref linkend="zone_transfers"/>.
+ </para>
+ </listitem>
+ </varlistentry>
+
+
+ <varlistentry>
+ <term><command>notify-source</command></term>
+ <listitem>
+ <para>
+ See the description of
+ <command>notify-source</command> in <xref linkend="zone_transfers"/>.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>notify-source-v6</command></term>
+ <listitem>
+ <para>
+ See the description of
+ <command>notify-source-v6</command> in <xref linkend="zone_transfers"/>.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>min-refresh-time</command></term>
+ <term><command>max-refresh-time</command></term>
+ <term><command>min-retry-time</command></term>
+ <term><command>max-retry-time</command></term>
+ <listitem>
+ <para>
+ See the description in <xref linkend="tuning"/>.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>ixfr-from-differences</command></term>
+ <listitem>
+ <para>
+ See the description of
+ <command>ixfr-from-differences</command> in <xref linkend="boolean_options"/>.
+ (Note that the <command>ixfr-from-differences</command>
+ <userinput>master</userinput> and
+ <userinput>slave</userinput> choices are not
+ available at the zone level.)
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>key-directory</command></term>
+ <listitem>
+ <para>
+ See the description of
+ <command>key-directory</command> in <xref linkend="options"/>.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>auto-dnssec</command></term>
+ <listitem>
+ <para>
+ Zones configured for dynamic DNS may also use this
+ option to allow varying levels of automatic DNSSEC key
+ management. There are three possible settings:
+ </para>
+ <para>
+ <command>auto-dnssec allow;</command> permits
+ keys to be updated and the zone fully re-signed
+ whenever the user issues the command <command>rndc sign
+ <replaceable>zonename</replaceable></command>.
+ </para>
+ <para>
+ <command>auto-dnssec maintain;</command> includes the
+ above, but also automatically adjusts the zone's DNSSEC
+ keys on schedule, according to the keys' timing metadata
+ (see <xref linkend="man.dnssec-keygen"/> and
+ <xref linkend="man.dnssec-settime"/>). The command
+ <command>rndc sign
+ <replaceable>zonename</replaceable></command> causes
+ <command>named</command> to load keys from the key
+ repository and sign the zone with all keys that are
+ active.
+ <command>rndc loadkeys
+ <replaceable>zonename</replaceable></command> causes
+ <command>named</command> to load keys from the key
+ repository and schedule key maintenance events to occur
+ in the future, but it does not sign the full zone
+ immediately. Note: once keys have been loaded for a
+ zone the first time, the repository will be searched
+ for changes periodically, regardless of whether
+ <command>rndc loadkeys</command> is used. The recheck
+ interval is defined by
+ <command>dnssec-loadkeys-interval</command>.)
+ </para>
+ <para>
+ The default setting is <command>auto-dnssec off</command>.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>serial-update-method</command></term>
+ <listitem>
+ <para>
+ Zones configured for dynamic DNS may use this
+ option to set the update method that will be used for
+ the zone serial number in the SOA record.
+ </para>
+ <para>
+ With the default setting of
+ <command>serial-update-method increment;</command>, the
+ SOA serial number will be incremented by one each time
+ the zone is updated.
+ </para>
+ <para>
+ When set to
+ <command>serial-update-method unixtime;</command>, the
+ SOA serial number will be set to the number of seconds
+ since the UNIX epoch, unless the serial number is
+ already greater than or equal to that value, in which
+ case it is simply incremented by one.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>inline-signing</command></term>
+ <listitem>
+ <para>
+ If <literal>yes</literal>, this enables
+ "bump in the wire" signing of a zone, where a
+ unsigned zone is transferred in or loaded from
+ disk and a signed version of the zone is served,
+ with possibly, a different serial number. This
+ behaviour is disabled by default.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>multi-master</command></term>
+ <listitem>
+ <para>
+ See the description of <command>multi-master</command> in
+ <xref linkend="boolean_options"/>.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>masterfile-format</command></term>
+ <listitem>
+ <para>
+ See the description of <command>masterfile-format</command>
+ in <xref linkend="tuning"/>.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>dnssec-secure-to-insecure</command></term>
+ <listitem>
+ <para>
+ See the description of
+ <command>dnssec-secure-to-insecure</command> in <xref linkend="boolean_options"/>.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ </variablelist>
+
+ </sect3>
+ <sect3 id="dynamic_update_policies">
+ <title>Dynamic Update Policies</title>
+ <para><acronym>BIND</acronym> 9 supports two alternative
+ methods of granting clients the right to perform
+ dynamic updates to a zone, configured by the
+ <command>allow-update</command> and
+ <command>update-policy</command> option, respectively.
+ </para>
+ <para>
+ The <command>allow-update</command> clause works the
+ same way as in previous versions of <acronym>BIND</acronym>.
+ It grants given clients the permission to update any
+ record of any name in the zone.
+ </para>
+ <para>
+ The <command>update-policy</command> clause
+ allows more fine-grained control over what updates are
+ allowed. A set of rules is specified, where each rule
+ either grants or denies permissions for one or more
+ names to be updated by one or more identities. If
+ the dynamic update request message is signed (that is,
+ it includes either a TSIG or SIG(0) record), the
+ identity of the signer can be determined.
+ </para>
+ <para>
+ Rules are specified in the <command>update-policy</command>
+ zone option, and are only meaningful for master zones.
+ When the <command>update-policy</command> statement
+ is present, it is a configuration error for the
+ <command>allow-update</command> statement to be
+ present. The <command>update-policy</command> statement
+ only examines the signer of a message; the source
+ address is not relevant.
+ </para>
+ <para>
+ There is a pre-defined <command>update-policy</command>
+ rule which can be switched on with the command
+ <command>update-policy local;</command>.
+ Switching on this rule in a zone causes
+ <command>named</command> to generate a TSIG session
+ key and place it in a file, and to allow that key
+ to update the zone. (By default, the file is
+ <filename>/var/run/named/session.key</filename>, the key
+ name is "local-ddns" and the key algorithm is HMAC-SHA256,
+ but these values are configurable with the
+ <command>session-keyfile</command>,
+ <command>session-keyname</command> and
+ <command>session-keyalg</command> options, respectively).
+ </para>
+ <para>
+ A client running on the local system, and with appropriate
+ permissions, may read that file and use the key to sign update
+ requests. The zone's update policy will be set to allow that
+ key to change any record within the zone. Assuming the
+ key name is "local-ddns", this policy is equivalent to:
+ </para>
+
+ <programlisting>update-policy { grant local-ddns zonesub any; };
+ </programlisting>
+
+ <para>
+ The command <command>nsupdate -l</command> sends update
+ requests to localhost, and signs them using the session key.
+ </para>
+
+ <para>
+ Other rule definitions look like this:
+ </para>
+
+<programlisting>
+( <command>grant</command> | <command>deny</command> ) <replaceable>identity</replaceable> <replaceable>nametype</replaceable> <optional> <replaceable>name</replaceable> </optional> <optional> <replaceable>types</replaceable> </optional>
+</programlisting>
+
+ <para>
+ Each rule grants or denies privileges. Once a message has
+ successfully matched a rule, the operation is immediately
+ granted or denied and no further rules are examined. A rule
+ is matched when the signer matches the identity field, the
+ name matches the name field in accordance with the nametype
+ field, and the type matches the types specified in the type
+ field.
+ </para>
+ <para>
+ No signer is required for <replaceable>tcp-self</replaceable>
+ or <replaceable>6to4-self</replaceable> however the standard
+ reverse mapping / prefix conversion must match the identity
+ field.
+ </para>
+ <para>
+ The identity field specifies a name or a wildcard
+ name. Normally, this is the name of the TSIG or
+ SIG(0) key used to sign the update request. When a
+ TKEY exchange has been used to create a shared secret,
+ the identity of the shared secret is the same as the
+ identity of the key used to authenticate the TKEY
+ exchange. TKEY is also the negotiation method used
+ by GSS-TSIG, which establishes an identity that is
+ the Kerberos principal of the client, such as
+ <userinput>"user@host.domain"</userinput>. When the
+ <replaceable>identity</replaceable> field specifies
+ a wildcard name, it is subject to DNS wildcard
+ expansion, so the rule will apply to multiple identities.
+ The <replaceable>identity</replaceable> field must
+ contain a fully-qualified domain name.
+ </para>
+ <para>
+ For nametypes <varname>krb5-self</varname>,
+ <varname>ms-self</varname>, <varname>krb5-subdomain</varname>,
+ and <varname>ms-subdomain</varname> the
+ <replaceable>identity</replaceable> field specifies
+ the Windows or Kerberos realm of the machine belongs to.
+ </para>
+ <para>
+ The <replaceable>nametype</replaceable> field has 13
+ values:
+ <varname>name</varname>, <varname>subdomain</varname>,
+ <varname>wildcard</varname>, <varname>self</varname>,
+ <varname>selfsub</varname>, <varname>selfwild</varname>,
+ <varname>krb5-self</varname>, <varname>ms-self</varname>,
+ <varname>krb5-subdomain</varname>,
+ <varname>ms-subdomain</varname>,
+ <varname>tcp-self</varname>, <varname>6to4-self</varname>,
+ <varname>zonesub</varname>, and <varname>external</varname>.
+ </para>
+ <informaltable>
+ <tgroup cols="2" colsep="0" rowsep="0" tgroupstyle="4Level-table">
+ <colspec colname="1" colnum="1" colsep="0" colwidth="0.819in"/>
+ <colspec colname="2" colnum="2" colsep="0" colwidth="3.681in"/>
+ <tbody>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ <varname>name</varname>
+ </para>
+ </entry> <entry colname="2">
+ <para>
+ Exact-match semantics. This rule matches
+ when the name being updated is identical
+ to the contents of the
+ <replaceable>name</replaceable> field.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ <varname>subdomain</varname>
+ </para>
+ </entry> <entry colname="2">
+ <para>
+ This rule matches when the name being updated
+ is a subdomain of, or identical to, the
+ contents of the <replaceable>name</replaceable>
+ field.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ <varname>zonesub</varname>
+ </para>
+ </entry> <entry colname="2">
+ <para>
+ This rule is similar to subdomain, except that
+ it matches when the name being updated is a
+ subdomain of the zone in which the
+ <command>update-policy</command> statement
+ appears. This obviates the need to type the zone
+ name twice, and enables the use of a standard
+ <command>update-policy</command> statement in
+ multiple zones without modification.
+ </para>
+ <para>
+ When this rule is used, the
+ <replaceable>name</replaceable> field is omitted.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ <varname>wildcard</varname>
+ </para>
+ </entry> <entry colname="2">
+ <para>
+ The <replaceable>name</replaceable> field
+ is subject to DNS wildcard expansion, and
+ this rule matches when the name being updated
+ name is a valid expansion of the wildcard.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ <varname>self</varname>
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ This rule matches when the name being updated
+ matches the contents of the
+ <replaceable>identity</replaceable> field.
+ The <replaceable>name</replaceable> field
+ is ignored, but should be the same as the
+ <replaceable>identity</replaceable> field.
+ The <varname>self</varname> nametype is
+ most useful when allowing using one key per
+ name to update, where the key has the same
+ name as the name to be updated. The
+ <replaceable>identity</replaceable> would
+ be specified as <constant>*</constant> (an asterisk) in
+ this case.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ <varname>selfsub</varname>
+ </para>
+ </entry> <entry colname="2">
+ <para>
+ This rule is similar to <varname>self</varname>
+ except that subdomains of <varname>self</varname>
+ can also be updated.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ <varname>selfwild</varname>
+ </para>
+ </entry> <entry colname="2">
+ <para>
+ This rule is similar to <varname>self</varname>
+ except that only subdomains of
+ <varname>self</varname> can be updated.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ <varname>ms-self</varname>
+ </para>
+ </entry> <entry colname="2">
+ <para>
+ This rule takes a Windows machine principal
+ (machine$@REALM) for machine in REALM and
+ and converts it machine.realm allowing the machine
+ to update machine.realm. The REALM to be matched
+ is specified in the <replaceable>identity</replaceable>
+ field.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ <varname>ms-subdomain</varname>
+ </para>
+ </entry> <entry colname="2">
+ <para>
+ This rule takes a Windows machine principal
+ (machine$@REALM) for machine in REALM and
+ converts it to machine.realm allowing the machine
+ to update subdomains of machine.realm. The REALM
+ to be matched is specified in the
+ <replaceable>identity</replaceable> field.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ <varname>krb5-self</varname>
+ </para>
+ </entry> <entry colname="2">
+ <para>
+ This rule takes a Kerberos machine principal
+ (host/machine@REALM) for machine in REALM and
+ and converts it machine.realm allowing the machine
+ to update machine.realm. The REALM to be matched
+ is specified in the <replaceable>identity</replaceable>
+ field.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ <varname>krb5-subdomain</varname>
+ </para>
+ </entry> <entry colname="2">
+ <para>
+ This rule takes a Kerberos machine principal
+ (host/machine@REALM) for machine in REALM and
+ converts it to machine.realm allowing the machine
+ to update subdomains of machine.realm. The REALM
+ to be matched is specified in the
+ <replaceable>identity</replaceable> field.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ <varname>tcp-self</varname>
+ </para>
+ </entry> <entry colname="2">
+ <para>
+ Allow updates that have been sent via TCP and
+ for which the standard mapping from the initiating
+ IP address into the IN-ADDR.ARPA and IP6.ARPA
+ namespaces match the name to be updated.
+ </para>
+ <note>
+ It is theoretically possible to spoof these TCP
+ sessions.
+ </note>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ <varname>6to4-self</varname>
+ </para>
+ </entry> <entry colname="2">
+ <para>
+ Allow the 6to4 prefix to be update by any TCP
+ connection from the 6to4 network or from the
+ corresponding IPv4 address. This is intended
+ to allow NS or DNAME RRsets to be added to the
+ reverse tree.
+ </para>
+ <note>
+ It is theoretically possible to spoof these TCP
+ sessions.
+ </note>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ <varname>external</varname>
+ </para>
+ </entry> <entry colname="2">
+ <para>
+ This rule allows <command>named</command>
+ to defer the decision of whether to allow a
+ given update to an external daemon.
+ </para>
+ <para>
+ The method of communicating with the daemon is
+ specified in the <replaceable>identity</replaceable>
+ field, the format of which is
+ "<constant>local:</constant><replaceable>path</replaceable>",
+ where <replaceable>path</replaceable> is the location
+ of a UNIX-domain socket. (Currently, "local" is the
+ only supported mechanism.)
+ </para>
+ <para>
+ Requests to the external daemon are sent over the
+ UNIX-domain socket as datagrams with the following
+ format:
+ </para>
+ <programlisting>
+ Protocol version number (4 bytes, network byte order, currently 1)
+ Request length (4 bytes, network byte order)
+ Signer (null-terminated string)
+ Name (null-terminated string)
+ TCP source address (null-terminated string)
+ Rdata type (null-terminated string)
+ Key (null-terminated string)
+ TKEY token length (4 bytes, network byte order)
+ TKEY token (remainder of packet)</programlisting>
+ <para>
+ The daemon replies with a four-byte value in
+ network byte order, containing either 0 or 1; 0
+ indicates that the specified update is not
+ permitted, and 1 indicates that it is.
+ </para>
+ </entry>
+ </row>
+ </tbody>
+ </tgroup>
+ </informaltable>
+
+ <para>
+ In all cases, the <replaceable>name</replaceable>
+ field must specify a fully-qualified domain name.
+ </para>
+
+ <para>
+ If no types are explicitly specified, this rule matches
+ all types except RRSIG, NS, SOA, NSEC and NSEC3. Types
+ may be specified by name, including "ANY" (ANY matches
+ all types except NSEC and NSEC3, which can never be
+ updated). Note that when an attempt is made to delete
+ all records associated with a name, the rules are
+ checked for each existing record type.
+ </para>
+ </sect3>
+
+ <sect3>
+ <title>Multiple views</title>
+ <para>
+ When multiple views are in use, a zone may be
+ referenced by more than one of them. Often, the views
+ will contain different zones with the same name, allowing
+ different clients to receive different answers for the same
+ queries. At times, however, it is desirable for multiple
+ views to contain identical zones. The
+ <command>in-view</command> zone option provides an efficient
+ way to do this: it allows a view to reference a zone that
+ was defined in a previously configured view. Example:
+ </para>
+ <programlisting>
+view internal {
+ match-clients { 10/8; };
+
+ zone example.com {
+ type master;
+ file "example-external.db";
+ };
+};
+
+view external {
+ match-clients { any; };
+
+ zone example.com {
+ in-view internal;
+ };
+};
+ </programlisting>
+ <para>
+ An <command>in-view</command> option cannot refer to a view
+ that is configured later in the configuration file.
+ </para>
+ <para>
+ A <command>zone</command> statement which uses the
+ <command>in-view</command> option may not use any other
+ options with the exception of <command>forward</command>
+ and <command>forwarders</command>. (These options control
+ the behavior of the containing view, rather than changing
+ the zone object itself.)
+ </para>
+ </sect3>
+
+ </sect2>
+ </sect1>
+ <sect1>
+ <title>Zone File</title>
+ <sect2 id="types_of_resource_records_and_when_to_use_them">
+ <title>Types of Resource Records and When to Use Them</title>
+ <para>
+ This section, largely borrowed from RFC 1034, describes the
+ concept of a Resource Record (RR) and explains when each is used.
+ Since the publication of RFC 1034, several new RRs have been
+ identified
+ and implemented in the DNS. These are also included.
+ </para>
+ <sect3>
+ <title>Resource Records</title>
+
+ <para>
+ A domain name identifies a node. Each node has a set of
+ resource information, which may be empty. The set of resource
+ information associated with a particular name is composed of
+ separate RRs. The order of RRs in a set is not significant and
+ need not be preserved by name servers, resolvers, or other
+ parts of the DNS. However, sorting of multiple RRs is
+ permitted for optimization purposes, for example, to specify
+ that a particular nearby server be tried first. See <xref linkend="the_sortlist_statement"/> and <xref linkend="rrset_ordering"/>.
+ </para>
+
+ <para>
+ The components of a Resource Record are:
+ </para>
+ <informaltable colsep="0" rowsep="0">
+ <tgroup cols="2" colsep="0" rowsep="0" tgroupstyle="4Level-table">
+ <colspec colname="1" colnum="1" colsep="0" colwidth="1.000in"/>
+ <colspec colname="2" colnum="2" colsep="0" colwidth="3.500in"/>
+ <tbody>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ owner name
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ The domain name where the RR is found.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ type
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ An encoded 16-bit value that specifies
+ the type of the resource record.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ TTL
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ The time-to-live of the RR. This field
+ is a 32-bit integer in units of seconds, and is
+ primarily used by
+ resolvers when they cache RRs. The TTL describes how
+ long a RR can
+ be cached before it should be discarded.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ class
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ An encoded 16-bit value that identifies
+ a protocol family or instance of a protocol.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ RDATA
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ The resource data. The format of the
+ data is type (and sometimes class) specific.
+ </para>
+ </entry>
+ </row>
+ </tbody>
+ </tgroup>
+ </informaltable>
+ <para>
+ The following are <emphasis>types</emphasis> of valid RRs:
+ </para>
+ <informaltable colsep="0" rowsep="0">
+ <tgroup cols="2" colsep="0" rowsep="0" tgroupstyle="4Level-table">
+ <colspec colname="1" colnum="1" colsep="0" colwidth="0.875in"/>
+ <colspec colname="2" colnum="2" colsep="0" colwidth="3.625in"/>
+ <tbody>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ A
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ A host address. In the IN class, this is a
+ 32-bit IP address. Described in RFC 1035.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ AAAA
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ IPv6 address. Described in RFC 1886.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ A6
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ IPv6 address. This can be a partial
+ address (a suffix) and an indirection to the name
+ where the rest of the
+ address (the prefix) can be found. Experimental.
+ Described in RFC 2874.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ AFSDB
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ Location of AFS database servers.
+ Experimental. Described in RFC 1183.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ APL
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ Address prefix list. Experimental.
+ Described in RFC 3123.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ CERT
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ Holds a digital certificate.
+ Described in RFC 2538.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ CNAME
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ Identifies the canonical name of an alias.
+ Described in RFC 1035.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ DHCID
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ Is used for identifying which DHCP client is
+ associated with this name. Described in RFC 4701.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ DNAME
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ Replaces the domain name specified with
+ another name to be looked up, effectively aliasing an
+ entire
+ subtree of the domain name space rather than a single
+ record
+ as in the case of the CNAME RR.
+ Described in RFC 2672.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ DNSKEY
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ Stores a public key associated with a signed
+ DNS zone. Described in RFC 4034.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ DS
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ Stores the hash of a public key associated with a
+ signed DNS zone. Described in RFC 4034.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ GPOS
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ Specifies the global position. Superseded by LOC.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ HINFO
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ Identifies the CPU and OS used by a host.
+ Described in RFC 1035.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ IPSECKEY
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ Provides a method for storing IPsec keying material in
+ DNS. Described in RFC 4025.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ ISDN
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ Representation of ISDN addresses.
+ Experimental. Described in RFC 1183.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ KEY
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ Stores a public key associated with a
+ DNS name. Used in original DNSSEC; replaced
+ by DNSKEY in DNSSECbis, but still used with
+ SIG(0). Described in RFCs 2535 and 2931.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ KX
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ Identifies a key exchanger for this
+ DNS name. Described in RFC 2230.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ LOC
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ For storing GPS info. Described in RFC 1876.
+ Experimental.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ MX
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ Identifies a mail exchange for the domain with
+ a 16-bit preference value (lower is better)
+ followed by the host name of the mail exchange.
+ Described in RFC 974, RFC 1035.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ NAPTR
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ Name authority pointer. Described in RFC 2915.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ NSAP
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ A network service access point.
+ Described in RFC 1706.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ NS
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ The authoritative name server for the
+ domain. Described in RFC 1035.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ NSEC
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ Used in DNSSECbis to securely indicate that
+ RRs with an owner name in a certain name interval do
+ not exist in
+ a zone and indicate what RR types are present for an
+ existing name.
+ Described in RFC 4034.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ NSEC3
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ Used in DNSSECbis to securely indicate that
+ RRs with an owner name in a certain name
+ interval do not exist in a zone and indicate
+ what RR types are present for an existing
+ name. NSEC3 differs from NSEC in that it
+ prevents zone enumeration but is more
+ computationally expensive on both the server
+ and the client than NSEC. Described in RFC
+ 5155.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ NSEC3PARAM
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ Used in DNSSECbis to tell the authoritative
+ server which NSEC3 chains are available to use.
+ Described in RFC 5155.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ NXT
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ Used in DNSSEC to securely indicate that
+ RRs with an owner name in a certain name interval do
+ not exist in
+ a zone and indicate what RR types are present for an
+ existing name.
+ Used in original DNSSEC; replaced by NSEC in
+ DNSSECbis.
+ Described in RFC 2535.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ PTR
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ A pointer to another part of the domain
+ name space. Described in RFC 1035.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ PX
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ Provides mappings between RFC 822 and X.400
+ addresses. Described in RFC 2163.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ RP
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ Information on persons responsible
+ for the domain. Experimental. Described in RFC 1183.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ RRSIG
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ Contains DNSSECbis signature data. Described
+ in RFC 4034.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ RT
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ Route-through binding for hosts that
+ do not have their own direct wide area network
+ addresses.
+ Experimental. Described in RFC 1183.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ SIG
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ Contains DNSSEC signature data. Used in
+ original DNSSEC; replaced by RRSIG in
+ DNSSECbis, but still used for SIG(0).
+ Described in RFCs 2535 and 2931.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ SOA
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ Identifies the start of a zone of authority.
+ Described in RFC 1035.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ SPF
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ Contains the Sender Policy Framework information
+ for a given email domain. Described in RFC 4408.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ SRV
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ Information about well known network
+ services (replaces WKS). Described in RFC 2782.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ SSHFP
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ Provides a way to securely publish a secure shell key's
+ fingerprint. Described in RFC 4255.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ TXT
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ Text records. Described in RFC 1035.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ WKS
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ Information about which well known
+ network services, such as SMTP, that a domain
+ supports. Historical.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ X25
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ Representation of X.25 network addresses.
+ Experimental. Described in RFC 1183.
+ </para>
+ </entry>
+ </row>
+ </tbody>
+ </tgroup>
+ </informaltable>
+ <para>
+ The following <emphasis>classes</emphasis> of resource records
+ are currently valid in the DNS:
+ </para>
+ <informaltable colsep="0" rowsep="0"><tgroup cols="2" colsep="0" rowsep="0" tgroupstyle="4Level-table">
+ <colspec colname="1" colnum="1" colsep="0" colwidth="0.875in"/>
+ <colspec colname="2" colnum="2" colsep="0" colwidth="3.625in"/>
+ <tbody>
+
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ IN
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ The Internet.
+ </para>
+ </entry>
+ </row>
+
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ CH
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ Chaosnet, a LAN protocol created at MIT in the
+ mid-1970s.
+ Rarely used for its historical purpose, but reused for
+ BIND's
+ built-in server information zones, e.g.,
+ <literal>version.bind</literal>.
+ </para>
+ </entry>
+ </row>
+
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ HS
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ Hesiod, an information service
+ developed by MIT's Project Athena. It is used to share
+ information
+ about various systems databases, such as users,
+ groups, printers
+ and so on.
+ </para>
+ </entry>
+ </row>
+
+ </tbody>
+ </tgroup>
+ </informaltable>
+
+ <para>
+ The owner name is often implicit, rather than forming an
+ integral
+ part of the RR. For example, many name servers internally form
+ tree
+ or hash structures for the name space, and chain RRs off nodes.
+ The remaining RR parts are the fixed header (type, class, TTL)
+ which is consistent for all RRs, and a variable part (RDATA)
+ that
+ fits the needs of the resource being described.
+ </para>
+ <para>
+ The meaning of the TTL field is a time limit on how long an
+ RR can be kept in a cache. This limit does not apply to
+ authoritative
+ data in zones; it is also timed out, but by the refreshing
+ policies
+ for the zone. The TTL is assigned by the administrator for the
+ zone where the data originates. While short TTLs can be used to
+ minimize caching, and a zero TTL prohibits caching, the
+ realities
+ of Internet performance suggest that these times should be on
+ the
+ order of days for the typical host. If a change can be
+ anticipated,
+ the TTL can be reduced prior to the change to minimize
+ inconsistency
+ during the change, and then increased back to its former value
+ following
+ the change.
+ </para>
+ <para>
+ The data in the RDATA section of RRs is carried as a combination
+ of binary strings and domain names. The domain names are
+ frequently
+ used as "pointers" to other data in the DNS.
+ </para>
+ </sect3>
+ <sect3>
+ <title>Textual expression of RRs</title>
+ <para>
+ RRs are represented in binary form in the packets of the DNS
+ protocol, and are usually represented in highly encoded form
+ when
+ stored in a name server or resolver. In the examples provided
+ in
+ RFC 1034, a style similar to that used in master files was
+ employed
+ in order to show the contents of RRs. In this format, most RRs
+ are shown on a single line, although continuation lines are
+ possible
+ using parentheses.
+ </para>
+ <para>
+ The start of the line gives the owner of the RR. If a line
+ begins with a blank, then the owner is assumed to be the same as
+ that of the previous RR. Blank lines are often included for
+ readability.
+ </para>
+ <para>
+ Following the owner, we list the TTL, type, and class of the
+ RR. Class and type use the mnemonics defined above, and TTL is
+ an integer before the type field. In order to avoid ambiguity
+ in
+ parsing, type and class mnemonics are disjoint, TTLs are
+ integers,
+ and the type mnemonic is always last. The IN class and TTL
+ values
+ are often omitted from examples in the interests of clarity.
+ </para>
+ <para>
+ The resource data or RDATA section of the RR are given using
+ knowledge of the typical representation for the data.
+ </para>
+ <para>
+ For example, we might show the RRs carried in a message as:
+ </para>
+ <informaltable colsep="0" rowsep="0"><tgroup cols="3" colsep="0" rowsep="0" tgroupstyle="4Level-table">
+ <colspec colname="1" colnum="1" colsep="0" colwidth="1.381in"/>
+ <colspec colname="2" colnum="2" colsep="0" colwidth="1.020in"/>
+ <colspec colname="3" colnum="3" colsep="0" colwidth="2.099in"/>
+ <tbody>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ <literal>ISI.EDU.</literal>
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ <literal>MX</literal>
+ </para>
+ </entry>
+ <entry colname="3">
+ <para>
+ <literal>10 VENERA.ISI.EDU.</literal>
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para/>
+ </entry>
+ <entry colname="2">
+ <para>
+ <literal>MX</literal>
+ </para>
+ </entry>
+ <entry colname="3">
+ <para>
+ <literal>10 VAXA.ISI.EDU</literal>
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ <literal>VENERA.ISI.EDU</literal>
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ <literal>A</literal>
+ </para>
+ </entry>
+ <entry colname="3">
+ <para>
+ <literal>128.9.0.32</literal>
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para/>
+ </entry>
+ <entry colname="2">
+ <para>
+ <literal>A</literal>
+ </para>
+ </entry>
+ <entry colname="3">
+ <para>
+ <literal>10.1.0.52</literal>
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ <literal>VAXA.ISI.EDU</literal>
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ <literal>A</literal>
+ </para>
+ </entry>
+ <entry colname="3">
+ <para>
+ <literal>10.2.0.27</literal>
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para/>
+ </entry>
+ <entry colname="2">
+ <para>
+ <literal>A</literal>
+ </para>
+ </entry>
+ <entry colname="3">
+ <para>
+ <literal>128.9.0.33</literal>
+ </para>
+ </entry>
+ </row>
+ </tbody>
+ </tgroup>
+ </informaltable>
+ <para>
+ The MX RRs have an RDATA section which consists of a 16-bit
+ number followed by a domain name. The address RRs use a
+ standard
+ IP address format to contain a 32-bit internet address.
+ </para>
+ <para>
+ The above example shows six RRs, with two RRs at each of three
+ domain names.
+ </para>
+ <para>
+ Similarly we might see:
+ </para>
+ <informaltable colsep="0" rowsep="0"><tgroup cols="3" colsep="0" rowsep="0" tgroupstyle="4Level-table">
+ <colspec colname="1" colnum="1" colsep="0" colwidth="1.491in"/>
+ <colspec colname="2" colnum="2" colsep="0" colwidth="1.067in"/>
+ <colspec colname="3" colnum="3" colsep="0" colwidth="2.067in"/>
+ <tbody>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ <literal>XX.LCS.MIT.EDU.</literal>
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ <literal>IN A</literal>
+ </para>
+ </entry>
+ <entry colname="3">
+ <para>
+ <literal>10.0.0.44</literal>
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1"/>
+ <entry colname="2">
+ <para>
+ <literal>CH A</literal>
+ </para>
+ </entry>
+ <entry colname="3">
+ <para>
+ <literal>MIT.EDU. 2420</literal>
+ </para>
+ </entry>
+ </row>
+ </tbody>
+ </tgroup>
+ </informaltable>
+ <para>
+ This example shows two addresses for
+ <literal>XX.LCS.MIT.EDU</literal>, each of a different class.
+ </para>
+ </sect3>
+ </sect2>
+
+ <sect2>
+ <title>Discussion of MX Records</title>
+
+ <para>
+ As described above, domain servers store information as a
+ series of resource records, each of which contains a particular
+ piece of information about a given domain name (which is usually,
+ but not always, a host). The simplest way to think of a RR is as
+ a typed pair of data, a domain name matched with a relevant datum,
+ and stored with some additional type information to help systems
+ determine when the RR is relevant.
+ </para>
+
+ <para>
+ MX records are used to control delivery of email. The data
+ specified in the record is a priority and a domain name. The
+ priority
+ controls the order in which email delivery is attempted, with the
+ lowest number first. If two priorities are the same, a server is
+ chosen randomly. If no servers at a given priority are responding,
+ the mail transport agent will fall back to the next largest
+ priority.
+ Priority numbers do not have any absolute meaning — they are
+ relevant
+ only respective to other MX records for that domain name. The
+ domain
+ name given is the machine to which the mail will be delivered.
+ It <emphasis>must</emphasis> have an associated address record
+ (A or AAAA) — CNAME is not sufficient.
+ </para>
+ <para>
+ For a given domain, if there is both a CNAME record and an
+ MX record, the MX record is in error, and will be ignored.
+ Instead,
+ the mail will be delivered to the server specified in the MX
+ record
+ pointed to by the CNAME.
+ For example:
+ </para>
+ <informaltable colsep="0" rowsep="0">
+ <tgroup cols="5" colsep="0" rowsep="0" tgroupstyle="3Level-table">
+ <colspec colname="1" colnum="1" colsep="0" colwidth="1.708in"/>
+ <colspec colname="2" colnum="2" colsep="0" colwidth="0.444in"/>
+ <colspec colname="3" colnum="3" colsep="0" colwidth="0.444in"/>
+ <colspec colname="4" colnum="4" colsep="0" colwidth="0.976in"/>
+ <colspec colname="5" colnum="5" colsep="0" colwidth="1.553in"/>
+ <tbody>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ <literal>example.com.</literal>
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ <literal>IN</literal>
+ </para>
+ </entry>
+ <entry colname="3">
+ <para>
+ <literal>MX</literal>
+ </para>
+ </entry>
+ <entry colname="4">
+ <para>
+ <literal>10</literal>
+ </para>
+ </entry>
+ <entry colname="5">
+ <para>
+ <literal>mail.example.com.</literal>
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para/>
+ </entry>
+ <entry colname="2">
+ <para>
+ <literal>IN</literal>
+ </para>
+ </entry>
+ <entry colname="3">
+ <para>
+ <literal>MX</literal>
+ </para>
+ </entry>
+ <entry colname="4">
+ <para>
+ <literal>10</literal>
+ </para>
+ </entry>
+ <entry colname="5">
+ <para>
+ <literal>mail2.example.com.</literal>
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para/>
+ </entry>
+ <entry colname="2">
+ <para>
+ <literal>IN</literal>
+ </para>
+ </entry>
+ <entry colname="3">
+ <para>
+ <literal>MX</literal>
+ </para>
+ </entry>
+ <entry colname="4">
+ <para>
+ <literal>20</literal>
+ </para>
+ </entry>
+ <entry colname="5">
+ <para>
+ <literal>mail.backup.org.</literal>
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ <literal>mail.example.com.</literal>
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ <literal>IN</literal>
+ </para>
+ </entry>
+ <entry colname="3">
+ <para>
+ <literal>A</literal>
+ </para>
+ </entry>
+ <entry colname="4">
+ <para>
+ <literal>10.0.0.1</literal>
+ </para>
+ </entry>
+ <entry colname="5">
+ <para/>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ <literal>mail2.example.com.</literal>
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ <literal>IN</literal>
+ </para>
+ </entry>
+ <entry colname="3">
+ <para>
+ <literal>A</literal>
+ </para>
+ </entry>
+ <entry colname="4">
+ <para>
+ <literal>10.0.0.2</literal>
+ </para>
+ </entry>
+ <entry colname="5">
+ <para/>
+ </entry>
+ </row>
+ </tbody>
+ </tgroup>
+ </informaltable><para>
+ Mail delivery will be attempted to <literal>mail.example.com</literal> and
+ <literal>mail2.example.com</literal> (in
+ any order), and if neither of those succeed, delivery to <literal>mail.backup.org</literal> will
+ be attempted.
+ </para>
+ </sect2>
+ <sect2 id="Setting_TTLs">
+ <title>Setting TTLs</title>
+ <para>
+ The time-to-live of the RR field is a 32-bit integer represented
+ in units of seconds, and is primarily used by resolvers when they
+ cache RRs. The TTL describes how long a RR can be cached before it
+ should be discarded. The following three types of TTL are
+ currently
+ used in a zone file.
+ </para>
+ <informaltable colsep="0" rowsep="0">
+ <tgroup cols="2" colsep="0" rowsep="0" tgroupstyle="3Level-table">
+ <colspec colname="1" colnum="1" colsep="0" colwidth="0.750in"/>
+ <colspec colname="2" colnum="2" colsep="0" colwidth="4.375in"/>
+ <tbody>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ SOA
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ The last field in the SOA is the negative
+ caching TTL. This controls how long other servers will
+ cache no-such-domain
+ (NXDOMAIN) responses from you.
+ </para>
+ <para>
+ The maximum time for
+ negative caching is 3 hours (3h).
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ $TTL
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ The $TTL directive at the top of the
+ zone file (before the SOA) gives a default TTL for every
+ RR without
+ a specific TTL set.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ RR TTLs
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ Each RR can have a TTL as the second
+ field in the RR, which will control how long other
+ servers can cache
+ the it.
+ </para>
+ </entry>
+ </row>
+ </tbody>
+ </tgroup>
+ </informaltable>
+ <para>
+ All of these TTLs default to units of seconds, though units
+ can be explicitly specified, for example, <literal>1h30m</literal>.
+ </para>
+ </sect2>
+ <sect2>
+ <title>Inverse Mapping in IPv4</title>
+ <para>
+ Reverse name resolution (that is, translation from IP address
+ to name) is achieved by means of the <emphasis>in-addr.arpa</emphasis> domain
+ and PTR records. Entries in the in-addr.arpa domain are made in
+ least-to-most significant order, read left to right. This is the
+ opposite order to the way IP addresses are usually written. Thus,
+ a machine with an IP address of 10.1.2.3 would have a
+ corresponding
+ in-addr.arpa name of
+ 3.2.1.10.in-addr.arpa. This name should have a PTR resource record
+ whose data field is the name of the machine or, optionally,
+ multiple
+ PTR records if the machine has more than one name. For example,
+ in the <optional>example.com</optional> domain:
+ </para>
+ <informaltable colsep="0" rowsep="0">
+ <tgroup cols="2" colsep="0" rowsep="0" tgroupstyle="3Level-table">
+ <colspec colname="1" colnum="1" colsep="0" colwidth="1.125in"/>
+ <colspec colname="2" colnum="2" colsep="0" colwidth="4.000in"/>
+ <tbody>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ <literal>$ORIGIN</literal>
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ <literal>2.1.10.in-addr.arpa</literal>
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para>
+ <literal>3</literal>
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ <literal>IN PTR foo.example.com.</literal>
+ </para>
+ </entry>
+ </row>
+ </tbody>
+ </tgroup>
+ </informaltable>
+ <note>
+ <para>
+ The <command>$ORIGIN</command> lines in the examples
+ are for providing context to the examples only — they do not
+ necessarily
+ appear in the actual usage. They are only used here to indicate
+ that the example is relative to the listed origin.
+ </para>
+ </note>
+ </sect2>
+ <sect2>
+ <title>Other Zone File Directives</title>
+ <para>
+ The Master File Format was initially defined in RFC 1035 and
+ has subsequently been extended. While the Master File Format
+ itself
+ is class independent all records in a Master File must be of the
+ same
+ class.
+ </para>
+ <para>
+ Master File Directives include <command>$ORIGIN</command>, <command>$INCLUDE</command>,
+ and <command>$TTL.</command>
+ </para>
+ <sect3>
+ <title>The <command>@</command> (at-sign)</title>
+ <para>
+ When used in the label (or name) field, the asperand or
+ at-sign (@) symbol represents the current origin.
+ At the start of the zone file, it is the
+ <<varname>zone_name</varname>> (followed by
+ trailing dot).
+ </para>
+ </sect3>
+ <sect3>
+ <title>The <command>$ORIGIN</command> Directive</title>
+ <para>
+ Syntax: <command>$ORIGIN</command>
+ <replaceable>domain-name</replaceable>
+ <optional><replaceable>comment</replaceable></optional>
+ </para>
+ <para><command>$ORIGIN</command>
+ sets the domain name that will be appended to any
+ unqualified records. When a zone is first read in there
+ is an implicit <command>$ORIGIN</command>
+ <<varname>zone_name</varname>><command>.</command>
+ (followed by trailing dot).
+ The current <command>$ORIGIN</command> is appended to
+ the domain specified in the <command>$ORIGIN</command>
+ argument if it is not absolute.
+ </para>
+
+<programlisting>
+$ORIGIN example.com.
+WWW CNAME MAIN-SERVER
+</programlisting>
+
+ <para>
+ is equivalent to
+ </para>
+
+<programlisting>
+WWW.EXAMPLE.COM. CNAME MAIN-SERVER.EXAMPLE.COM.
+</programlisting>
+
+ </sect3>
+ <sect3>
+ <title>The <command>$INCLUDE</command> Directive</title>
+ <para>
+ Syntax: <command>$INCLUDE</command>
+ <replaceable>filename</replaceable>
+ <optional>
+<replaceable>origin</replaceable> </optional>
+ <optional> <replaceable>comment</replaceable> </optional>
+ </para>
+ <para>
+ Read and process the file <filename>filename</filename> as
+ if it were included into the file at this point. If <command>origin</command> is
+ specified the file is processed with <command>$ORIGIN</command> set
+ to that value, otherwise the current <command>$ORIGIN</command> is
+ used.
+ </para>
+ <para>
+ The origin and the current domain name
+ revert to the values they had prior to the <command>$INCLUDE</command> once
+ the file has been read.
+ </para>
+ <note>
+ <para>
+ RFC 1035 specifies that the current origin should be restored
+ after
+ an <command>$INCLUDE</command>, but it is silent
+ on whether the current
+ domain name should also be restored. BIND 9 restores both of
+ them.
+ This could be construed as a deviation from RFC 1035, a
+ feature, or both.
+ </para>
+ </note>
+ </sect3>
+ <sect3>
+ <title>The <command>$TTL</command> Directive</title>
+ <para>
+ Syntax: <command>$TTL</command>
+ <replaceable>default-ttl</replaceable>
+ <optional>
+<replaceable>comment</replaceable> </optional>
+ </para>
+ <para>
+ Set the default Time To Live (TTL) for subsequent records
+ with undefined TTLs. Valid TTLs are of the range 0-2147483647
+ seconds.
+ </para>
+ <para><command>$TTL</command>
+ is defined in RFC 2308.
+ </para>
+ </sect3>
+ </sect2>
+ <sect2>
+ <title><acronym>BIND</acronym> Master File Extension: the <command>$GENERATE</command> Directive</title>
+ <para>
+ Syntax: <command>$GENERATE</command>
+ <replaceable>range</replaceable>
+ <replaceable>lhs</replaceable>
+ <optional><replaceable>ttl</replaceable></optional>
+ <optional><replaceable>class</replaceable></optional>
+ <replaceable>type</replaceable>
+ <replaceable>rhs</replaceable>
+ <optional><replaceable>comment</replaceable></optional>
+ </para>
+ <para><command>$GENERATE</command>
+ is used to create a series of resource records that only
+ differ from each other by an
+ iterator. <command>$GENERATE</command> can be used to
+ easily generate the sets of records required to support
+ sub /24 reverse delegations described in RFC 2317:
+ Classless IN-ADDR.ARPA delegation.
+ </para>
+
+<programlisting>$ORIGIN 0.0.192.IN-ADDR.ARPA.
+$GENERATE 1-2 @ NS SERVER$.EXAMPLE.
+$GENERATE 1-127 $ CNAME $.0</programlisting>
+
+ <para>
+ is equivalent to
+ </para>
+
+<programlisting>0.0.0.192.IN-ADDR.ARPA. NS SERVER1.EXAMPLE.
+0.0.0.192.IN-ADDR.ARPA. NS SERVER2.EXAMPLE.
+1.0.0.192.IN-ADDR.ARPA. CNAME 1.0.0.0.192.IN-ADDR.ARPA.
+2.0.0.192.IN-ADDR.ARPA. CNAME 2.0.0.0.192.IN-ADDR.ARPA.
+...
+127.0.0.192.IN-ADDR.ARPA. CNAME 127.0.0.0.192.IN-ADDR.ARPA.
+</programlisting>
+
+ <para>
+ Generate a set of A and MX records. Note the MX's right hand
+ side is a quoted string. The quotes will be stripped when the
+ right hand side is processed.
+ </para>
+
+<programlisting>
+$ORIGIN EXAMPLE.
+$GENERATE 1-127 HOST-$ A 1.2.3.$
+$GENERATE 1-127 HOST-$ MX "0 ."</programlisting>
+
+ <para>
+ is equivalent to
+ </para>
+
+<programlisting>HOST-1.EXAMPLE. A 1.2.3.1
+HOST-1.EXAMPLE. MX 0 .
+HOST-2.EXAMPLE. A 1.2.3.2
+HOST-2.EXAMPLE. MX 0 .
+HOST-3.EXAMPLE. A 1.2.3.3
+HOST-3.EXAMPLE. MX 0 .
+...
+HOST-127.EXAMPLE. A 1.2.3.127
+HOST-127.EXAMPLE. MX 0 .
+</programlisting>
+
+ <informaltable colsep="0" rowsep="0">
+ <tgroup cols="2" colsep="0" rowsep="0" tgroupstyle="3Level-table">
+ <colspec colname="1" colnum="1" colsep="0" colwidth="0.875in"/>
+ <colspec colname="2" colnum="2" colsep="0" colwidth="4.250in"/>
+ <tbody>
+ <row rowsep="0">
+ <entry colname="1">
+ <para><command>range</command></para>
+ </entry>
+ <entry colname="2">
+ <para>
+ This can be one of two forms: start-stop
+ or start-stop/step. If the first form is used, then step
+ is set to
+ 1. All of start, stop and step must be positive.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para><command>lhs</command></para>
+ </entry>
+ <entry colname="2">
+ <para>This
+ describes the owner name of the resource records
+ to be created. Any single <command>$</command>
+ (dollar sign)
+ symbols within the <command>lhs</command> string
+ are replaced by the iterator value.
+
+ To get a $ in the output, you need to escape the
+ <command>$</command> using a backslash
+ <command>\</command>,
+ e.g. <command>\$</command>. The
+ <command>$</command> may optionally be followed
+ by modifiers which change the offset from the
+ iterator, field width and base.
+
+ Modifiers are introduced by a
+ <command>{</command> (left brace) immediately following the
+ <command>$</command> as
+ <command>${offset[,width[,base]]}</command>.
+ For example, <command>${-20,3,d}</command>
+ subtracts 20 from the current value, prints the
+ result as a decimal in a zero-padded field of
+ width 3.
+
+ Available output forms are decimal
+ (<command>d</command>), octal
+ (<command>o</command>), hexadecimal
+ (<command>x</command> or <command>X</command>
+ for uppercase) and nibble
+ (<command>n</command> or <command>N</command>\
+ for uppercase). The default modifier is
+ <command>${0,0,d}</command>. If the
+ <command>lhs</command> is not absolute, the
+ current <command>$ORIGIN</command> is appended
+ to the name.
+ </para>
+ <para>
+ In nibble mode the value will be treated as
+ if it was a reversed hexadecimal string
+ with each hexadecimal digit as a separate
+ label. The width field includes the label
+ separator.
+ </para>
+ <para>
+ For compatibility with earlier versions,
+ <command>$$</command> is still recognized as
+ indicating a literal $ in the output.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para><command>ttl</command></para>
+ </entry>
+ <entry colname="2">
+ <para>
+ Specifies the time-to-live of the generated records. If
+ not specified this will be inherited using the
+ normal TTL inheritance rules.
+ </para>
+ <para><command>class</command>
+ and <command>ttl</command> can be
+ entered in either order.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para><command>class</command></para>
+ </entry>
+ <entry colname="2">
+ <para>
+ Specifies the class of the generated records.
+ This must match the zone class if it is
+ specified.
+ </para>
+ <para><command>class</command>
+ and <command>ttl</command> can be
+ entered in either order.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para><command>type</command></para>
+ </entry>
+ <entry colname="2">
+ <para>
+ Any valid type.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para><command>rhs</command></para>
+ </entry>
+ <entry colname="2">
+ <para>
+ <command>rhs</command>, optionally, quoted string.
+ </para>
+ </entry>
+ </row>
+ </tbody>
+ </tgroup>
+ </informaltable>
+ <para>
+ The <command>$GENERATE</command> directive is a <acronym>BIND</acronym> extension
+ and not part of the standard zone file format.
+ </para>
+ <para>
+ BIND 8 does not support the optional TTL and CLASS fields.
+ </para>
+ </sect2>
+
+ <sect2 id="zonefile_format">
+ <title>Additional File Formats</title>
+ <para>
+ In addition to the standard textual format, BIND 9
+ supports the ability to read or dump to zone files in
+ other formats.
+ </para>
+ <para>
+ The <constant>raw</constant> format is
+ a binary representation of zone data in a manner similar
+ to that used in zone transfers. Since it does not require
+ parsing text, load time is significantly reduced.
+ </para>
+ <para>
+ An even faster alternative is the <constant>map</constant>
+ format, which is an image of a <acronym>BIND</acronym> 9
+ in-memory zone database; it is capable of being loaded
+ directly into memory via the <command>mmap()</command>
+ function; the zone can begin serving queries almost
+ immediately.
+ </para>
+ <para>
+ For a primary server, a zone file in
+ <constant>raw</constant> or <constant>map</constant>
+ format is expected to be generated from a textual zone
+ file by the <command>named-compilezone</command> command.
+ For a secondary server or for a dynamic zone, it is automatically
+ generated (if this format is specified by the
+ <command>masterfile-format</command> option) when
+ <command>named</command> dumps the zone contents after
+ zone transfer or when applying prior updates.
+ </para>
+ <para>
+ If a zone file in a binary format needs manual modification,
+ it first must be converted to a textual form by the
+ <command>named-compilezone</command> command. All
+ necessary modification should go to the text file, which
+ should then be converted to the binary form by the
+ <command>named-compilezone</command> command again.
+ </para>
+ <para>
+ Note that <command>map</command> format is extremely
+ architecture-specific. A <constant>map</constant>
+ file <emphasis>cannot</emphasis> be used on a system
+ with different pointer size, endianness or data alignment
+ than the system on which it was generated, and should in
+ general be used only inside a single system.
+ While <constant>raw</constant> format uses
+ network byte order and avoids architecture-dependent
+ data alignment so that it is as portable as
+ possible, it is also primarily expected to be used
+ inside the same single system. To export a
+ zone file in either <constant>raw</constant> or
+ <constant>map</constant> format, or make a
+ portable backup of such a file, conversion to
+ <constant>text</constant> format is recommended.
+ </para>
+ </sect2>
+ </sect1>
+
+ <sect1 id="statistics">
+ <title>BIND9 Statistics</title>
+ <para>
+ <acronym>BIND</acronym> 9 maintains lots of statistics
+ information and provides several interfaces for users to
+ get access to the statistics.
+ The available statistics include all statistics counters
+ that were available in <acronym>BIND</acronym> 8 and
+ are meaningful in <acronym>BIND</acronym> 9,
+ and other information that is considered useful.
+ </para>
+
+ <para>
+ The statistics information is categorized into the following
+ sections.
+ </para>
+
+ <informaltable frame="all">
+ <tgroup cols="2">
+ <colspec colname="1" colnum="1" colsep="0" colwidth="3.300in"/>
+ <colspec colname="2" colnum="2" colsep="0" colwidth="2.625in"/>
+ <tbody>
+
+ <row rowsep="0">
+ <entry colname="1">
+ <para>Incoming Requests</para>
+ </entry>
+ <entry colname="2">
+ <para>
+ The number of incoming DNS requests for each OPCODE.
+ </para>
+ </entry>
+ </row>
+
+ <row rowsep="0">
+ <entry colname="1">
+ <para>Incoming Queries</para>
+ </entry>
+ <entry colname="2">
+ <para>
+ The number of incoming queries for each RR type.
+ </para>
+ </entry>
+ </row>
+
+ <row rowsep="0">
+ <entry colname="1">
+ <para>Outgoing Queries</para>
+ </entry>
+ <entry colname="2">
+ <para>
+ The number of outgoing queries for each RR
+ type sent from the internal resolver.
+ Maintained per view.
+ </para>
+ </entry>
+ </row>
+
+ <row rowsep="0">
+ <entry colname="1">
+ <para>Name Server Statistics</para>
+ </entry>
+ <entry colname="2">
+ <para>
+ Statistics counters about incoming request processing.
+ </para>
+ </entry>
+ </row>
+
+ <row rowsep="0">
+ <entry colname="1">
+ <para>Zone Maintenance Statistics</para>
+ </entry>
+ <entry colname="2">
+ <para>
+ Statistics counters regarding zone maintenance
+ operations such as zone transfers.
+ </para>
+ </entry>
+ </row>
+
+ <row rowsep="0">
+ <entry colname="1">
+ <para>Resolver Statistics</para>
+ </entry>
+ <entry colname="2">
+ <para>
+ Statistics counters about name resolution
+ performed in the internal resolver.
+ Maintained per view.
+ </para>
+ </entry>
+ </row>
+
+ <row rowsep="0">
+ <entry colname="1">
+ <para>Cache DB RRsets</para>
+ </entry>
+ <entry colname="2">
+ <para>
+ The number of RRsets per RR type and nonexistent
+ names stored in the cache database.
+ If the exclamation mark (!) is printed for a RR
+ type, it means that particular type of RRset is
+ known to be nonexistent (this is also known as
+ "NXRRSET"). If a hash mark (#) is present then
+ the RRset is marked for garbage collection.
+ Maintained per view.
+ </para>
+ </entry>
+ </row>
+
+ <row rowsep="0">
+ <entry colname="1">
+ <para>Socket I/O Statistics</para>
+ </entry>
+ <entry colname="2">
+ <para>
+ Statistics counters about network related events.
+ </para>
+ </entry>
+ </row>
+
+ </tbody>
+ </tgroup>
+ </informaltable>
+
+ <para>
+ A subset of Name Server Statistics is collected and shown
+ per zone for which the server has the authority when
+ <command>zone-statistics</command> is set to
+ <userinput>yes</userinput>.
+ These statistics counters are shown with their zone and view
+ names.
+ In some cases the view names are omitted for the default view.
+ </para>
+
+ <para>
+ There are currently two user interfaces to get access to the
+ statistics.
+ One is in the plain text format dumped to the file specified
+ by the <command>statistics-file</command> configuration option.
+ The other is remotely accessible via a statistics channel
+ when the <command>statistics-channels</command> statement
+ is specified in the configuration file
+ (see <xref linkend="statschannels"/>.)
+ </para>
+
+ <sect3 id="statsfile">
+ <title>The Statistics File</title>
+ <para>
+ The text format statistics dump begins with a line, like:
+ </para>
+ <para>
+ <command>+++ Statistics Dump +++ (973798949)</command>
+ </para>
+ <para>
+ The number in parentheses is a standard
+ Unix-style timestamp, measured as seconds since January 1, 1970.
+
+ Following
+ that line is a set of statistics information, which is categorized
+ as described above.
+ Each section begins with a line, like:
+ </para>
+
+ <para>
+ <command>++ Name Server Statistics ++</command>
+ </para>
+
+ <para>
+ Each section consists of lines, each containing the statistics
+ counter value followed by its textual description.
+ See below for available counters.
+ For brevity, counters that have a value of 0 are not shown
+ in the statistics file.
+ </para>
+
+ <para>
+ The statistics dump ends with the line where the
+ number is identical to the number in the beginning line; for example:
+ </para>
+ <para>
+ <command>--- Statistics Dump --- (973798949)</command>
+ </para>
+ </sect3>
+
+ <sect2 id="statistics_counters">
+ <title>Statistics Counters</title>
+ <para>
+ The following tables summarize statistics counters that
+ <acronym>BIND</acronym> 9 provides.
+ For each row of the tables, the leftmost column is the
+ abbreviated symbol name of that counter.
+ These symbols are shown in the statistics information
+ accessed via an HTTP statistics channel.
+ The rightmost column gives the description of the counter,
+ which is also shown in the statistics file
+ (but, in this document, possibly with slight modification
+ for better readability).
+ Additional notes may also be provided in this column.
+ When a middle column exists between these two columns,
+ it gives the corresponding counter name of the
+ <acronym>BIND</acronym> 8 statistics, if applicable.
+ </para>
+
+ <sect3>
+ <title>Name Server Statistics Counters</title>
+
+ <informaltable colsep="0" rowsep="0">
+ <tgroup cols="3" colsep="0" rowsep="0" tgroupstyle="4Level-table">
+ <colspec colname="1" colnum="1" colsep="0" colwidth="1.150in"/>
+ <colspec colname="2" colnum="2" colsep="0" colwidth="1.150in"/>
+ <colspec colname="3" colnum="3" colsep="0" colwidth="3.350in"/>
+ <tbody>
+ <row>
+ <entry colname="1">
+ <para>
+ <emphasis>Symbol</emphasis>
+ </para>
+ </entry>
+ <entry colname="2">
+ <para>
+ <emphasis>BIND8 Symbol</emphasis>
+ </para>
+ </entry>
+ <entry colname="3">
+ <para>
+ <emphasis>Description</emphasis>
+ </para>
+ </entry>
+ </row>
+
+ <row rowsep="0">
+ <entry colname="1">
+ <para><command>Requestv4</command></para>
+ </entry>
+ <entry colname="2">
+ <para><command>RQ</command></para>
+ </entry>
+ <entry colname="3">
+ <para>
+ IPv4 requests received.
+ Note: this also counts non query requests.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para><command>Requestv6</command></para>
+ </entry>
+ <entry colname="2">
+ <para><command>RQ</command></para>
+ </entry>
+ <entry colname="3">
+ <para>
+ IPv6 requests received.
+ Note: this also counts non query requests.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para><command>ReqEdns0</command></para>
+ </entry>
+ <entry colname="2">
+ <para><command></command></para>
+ </entry>
+ <entry colname="3">
+ <para>
+ Requests with EDNS(0) received.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para><command>ReqBadEDNSVer</command></para>
+ </entry>
+ <entry colname="2">
+ <para><command></command></para>
+ </entry>
+ <entry colname="3">
+ <para>
+ Requests with unsupported EDNS version received.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para><command>ReqTSIG</command></para>
+ </entry>
+ <entry colname="2">
+ <para><command></command></para>
+ </entry>
+ <entry colname="3">
+ <para>
+ Requests with TSIG received.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para><command>ReqSIG0</command></para>
+ </entry>
+ <entry colname="2">
+ <para><command></command></para>
+ </entry>
+ <entry colname="3">
+ <para>
+ Requests with SIG(0) received.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para><command>ReqBadSIG</command></para>
+ </entry>
+ <entry colname="2">
+ <para><command></command></para>
+ </entry>
+ <entry colname="3">
+ <para>
+ Requests with invalid (TSIG or SIG(0)) signature.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para><command>ReqTCP</command></para>
+ </entry>
+ <entry colname="2">
+ <para><command>RTCP</command></para>
+ </entry>
+ <entry colname="3">
+ <para>
+ TCP requests received.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para><command>AuthQryRej</command></para>
+ </entry>
+ <entry colname="2">
+ <para><command>RUQ</command></para>
+ </entry>
+ <entry colname="3">
+ <para>
+ Authoritative (non recursive) queries rejected.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para><command>RecQryRej</command></para>
+ </entry>
+ <entry colname="2">
+ <para><command>RURQ</command></para>
+ </entry>
+ <entry colname="3">
+ <para>
+ Recursive queries rejected.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para><command>XfrRej</command></para>
+ </entry>
+ <entry colname="2">
+ <para><command>RUXFR</command></para>
+ </entry>
+ <entry colname="3">
+ <para>
+ Zone transfer requests rejected.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para><command>UpdateRej</command></para>
+ </entry>
+ <entry colname="2">
+ <para><command>RUUpd</command></para>
+ </entry>
+ <entry colname="3">
+ <para>
+ Dynamic update requests rejected.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para><command>Response</command></para>
+ </entry>
+ <entry colname="2">
+ <para><command>SAns</command></para>
+ </entry>
+ <entry colname="3">
+ <para>
+ Responses sent.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
+ <entry colname="1">
+ <para><command>RespTruncated</command></para>
+ </entry>
+ <entry colname="2">
+ <para><command></command></para>
+ </entry>
+ <entry colname="3">
+ <para>
+ Truncated responses sent.
+ </para>
+ </entry>
+ </row>
+ <row rowsep="0">
<entry colname="1">
<para><command>RespEDNS0</command></para>
</entry>
</entry>
</row>
</tbody>
- </tgroup>
- </informaltable>
- </sect3>
+ </tgroup>
+ </informaltable>
+ </sect3>
<sect3>
- <title>Zone Maintenance Statistics Counters</title>
+ <title>Zone Maintenance Statistics Counters</title>
- <informaltable colsep="0" rowsep="0">
- <tgroup cols="2" colsep="0" rowsep="0" tgroupstyle="4Level-table">
+ <informaltable colsep="0" rowsep="0">
+ <tgroup cols="2" colsep="0" rowsep="0" tgroupstyle="4Level-table">
<colspec colname="1" colnum="1" colsep="0" colwidth="1.150in"/>
<colspec colname="2" colnum="2" colsep="0" colwidth="3.350in"/>
<tbody>
<row>
<entry colname="1">
+ <para>
<emphasis>Symbol</emphasis>
- </para>
+ </para>
</entry>
<entry colname="2">
+ <para>
<emphasis>Description</emphasis>
- </para>
+ </para>
</entry>
</row>
</entry>
</row>
</tbody>
- </tgroup>
- </informaltable>
+ </tgroup>
+ </informaltable>
</sect3>
<sect3>
- <title>Resolver Statistics Counters</title>
+ <title>Resolver Statistics Counters</title>
- <informaltable colsep="0" rowsep="0">
- <tgroup cols="3" colsep="0" rowsep="0" tgroupstyle="4Level-table">
+ <informaltable colsep="0" rowsep="0">
+ <tgroup cols="3" colsep="0" rowsep="0" tgroupstyle="4Level-table">
<colspec colname="1" colnum="1" colsep="0" colwidth="1.150in"/>
<colspec colname="2" colnum="2" colsep="0" colwidth="1.150in"/>
<colspec colname="3" colnum="3" colsep="0" colwidth="3.350in"/>
<tbody>
<row>
<entry colname="1">
+ <para>
<emphasis>Symbol</emphasis>
- </para>
+ </para>
</entry>
<entry colname="2">
+ <para>
<emphasis>BIND8 Symbol</emphasis>
- </para>
+ </para>
</entry>
<entry colname="3">
+ <para>
<emphasis>Description</emphasis>
- </para>
+ </para>
</entry>
</row>
</entry>
</row>
</tbody>
- </tgroup>
- </informaltable>
+ </tgroup>
+ </informaltable>
</sect3>
<sect3>
- <title>Socket I/O Statistics Counters</title>
+ <title>Socket I/O Statistics Counters</title>
<para>
Socket I/O statistics counters are defined per socket
</para>
<informaltable colsep="0" rowsep="0">
- <tgroup cols="2" colsep="0" rowsep="0" tgroupstyle="4Level-table">
+ <tgroup cols="2" colsep="0" rowsep="0" tgroupstyle="4Level-table">
<colspec colname="1" colnum="1" colsep="0" colwidth="1.150in"/>
<colspec colname="2" colnum="2" colsep="0" colwidth="3.350in"/>
<tbody>
<row>
<entry colname="1">
+ <para>
<emphasis>Symbol</emphasis>
- </para>
+ </para>
</entry>
<entry colname="2">
+ <para>
<emphasis>Description</emphasis>
- </para>
+ </para>
</entry>
</row>
</entry>
</row>
</tbody>
- </tgroup>
+ </tgroup>
</informaltable>
</sect3>
<sect3>
- <title>Compatibility with <emphasis>BIND</emphasis> 8 Counters</title>
+ <title>Compatibility with <emphasis>BIND</emphasis> 8 Counters</title>
<para>
Most statistics counters that were available
in <command>BIND</command> 8 are also supported in
in these tables.
</para>
- <variablelist>
- <varlistentry>
+ <variablelist>
+ <varlistentry>
<term><command>RFwdR,SFwdR</command></term>
<listitem>
<para>
</listitem>
</varlistentry>
- <varlistentry>
+ <varlistentry>
<term><command>RAXFR</command></term>
<listitem>
<para>
</listitem>
</varlistentry>
- <varlistentry>
+ <varlistentry>
<term><command>RIQ</command></term>
<listitem>
<para>
</listitem>
</varlistentry>
- <varlistentry>
+ <varlistentry>
<term><command>ROpts</command></term>
<listitem>
<para>
</varlistentry>
</variablelist>
</sect3>
- </sect2>
+ </sect2>
</sect1>
</chapter>
<chapter id="Bv9ARM.ch07">
<title><acronym>BIND</acronym> 9 Security Considerations</title>
<sect1 id="Access_Control_Lists">
- <title>Access Control Lists</title>
- Access Control Lists (ACLs) are address match lists that
- you can set up and nickname for future use in <command>allow-notify</command>,
- <command>allow-query</command>, <command>allow-query-on</command>,
+ <title>Access Control Lists</title>
+ <para>
+ Access Control Lists (ACLs) are address match lists that
+ you can set up and nickname for future use in <command>allow-notify</command>,
+ <command>allow-query</command>, <command>allow-query-on</command>,
<command>allow-recursion</command>, <command>allow-recursion-on</command>,
- <command>blackhole</command>, <command>allow-transfer</command>,
- etc.
- </para>
- Using ACLs allows you to have finer control over who can access
- your name server, without cluttering up your config files with huge
- lists of IP addresses.
- </para>
- It is a <emphasis>good idea</emphasis> to use ACLs, and to
- control access to your server. Limiting access to your server by
- outside parties can help prevent spoofing and denial of service (DoS) attacks against
- your server.
- </para>
- Here is an example of how to properly apply ACLs:
- </para>
+ <command>blackhole</command>, <command>allow-transfer</command>,
+ etc.
+ </para>
+ <para>
+ Using ACLs allows you to have finer control over who can access
+ your name server, without cluttering up your config files with huge
+ lists of IP addresses.
+ </para>
+ <para>
+ It is a <emphasis>good idea</emphasis> to use ACLs, and to
+ control access to your server. Limiting access to your server by
+ outside parties can help prevent spoofing and denial of service (DoS) attacks against
+ your server.
+ </para>
+ <para>
+ Here is an example of how to properly apply ACLs:
+ </para>
<programlisting>
// Set up an ACL named "bogusnets" that will block
// RFC1918 space and some reserved space, which is
// commonly used in spoofing attacks.
acl bogusnets {
- 0.0.0.0/8; 192.0.2.0/24; 224.0.0.0/3;
- 10.0.0.0/8; 172.16.0.0/12; 192.168.0.0/16;
+ 0.0.0.0/8; 192.0.2.0/24; 224.0.0.0/3;
+ 10.0.0.0/8; 172.16.0.0/12; 192.168.0.0/16;
};
// Set up an ACL called our-nets. Replace this with the
};
</programlisting>
- This allows recursive queries of the server from the outside
- unless recursion has been previously disabled.
- </para>
+ <para>
+ This allows recursive queries of the server from the outside
+ unless recursion has been previously disabled.
+ </para>
</sect1>
<sect1>
- <title><command>Chroot</command> and <command>Setuid</command></title>
+ <title><command>Chroot</command> and <command>Setuid</command></title>
+ <para>
On UNIX servers, it is possible to run <acronym>BIND</acronym>
in a <emphasis>chrooted</emphasis> environment (using
the <command>chroot()</command> function) by specifying
This can help improve system security by placing
<acronym>BIND</acronym> in a "sandbox", which will limit
the damage done if a server is compromised.
- </para>
-
Another useful feature in the UNIX version of <acronym>BIND</acronym> is the
- ability to run the daemon as an unprivileged user ( <option>-u</option> <replaceable>user</replaceable> ).
- We suggest running as an unprivileged user when using the <command>chroot</command> feature.
- </para>
-
Here is an example command line to load <acronym>BIND</acronym> in a <command>chroot</command> sandbox,
- <command>/var/named</command>, and to run <command>named</command> <command>setuid</command> to
- user 202:
- </para>
- <userinput>/usr/local/sbin/named -u 202 -t /var/named</userinput>
- </para>
-
- <sect2>
- <title>The <command>chroot</command> Environment</title>
-
- In order for a <command>chroot</command> environment
- to
- work properly in a particular directory
- (for example, <filename>/var/named</filename>),
- you will need to set up an environment that includes everything
-
<acronym>BIND</acronym> needs to run.
-
From <acronym>BIND</acronym>'s point of view, <filename>/var/named</filename> is
- the root of the filesystem. You will need to adjust the values of
- options like
- like <command>directory</command> and <command>pid-file</command> to account
- for this.
- </para>
- Unlike with earlier versions of BIND, you typically will
- <emphasis>not</emphasis> need to compile <command>named</command>
- statically nor install shared libraries under the new root.
- However, depending on your operating system, you may need
- to set up things like
- <filename>/dev/zero</filename>,
- <filename>/dev/random</filename>,
- <filename>/dev/log</filename>, and
- <filename>/etc/localtime</filename>.
- </para>
- </sect2>
-
- <sect2>
- <title>Using the <command>setuid</command> Function</title>
-
- Prior to running the <command>named</command> daemon,
- use
- the <command>touch</command> utility (to change file
- access and
- modification times) or the <command>chown</command>
- utility (to
- set the user id and/or group id) on files
-
to which you want <acronym>BIND</acronym>
- to write.
- </para>
+ </para>
+ <para>
+ Another useful feature in the UNIX version of <acronym>BIND</acronym> is the
+ ability to run the daemon as an unprivileged user ( <option>-u</option> <replaceable>user</replaceable> ).
+ We suggest running as an unprivileged user when using the <command>chroot</command> feature.
+ </para>
+ <para>
+ Here is an example command line to load <acronym>BIND</acronym> in a <command>chroot</command> sandbox,
+ <command>/var/named</command>, and to run <command>named</command> <command>setuid</command> to
+ user 202:
+ </para>
+ <para>
+ <userinput>/usr/local/sbin/named -u 202 -t /var/named</userinput>
+ </para>
+
+ <sect2>
+ <title>The <command>chroot</command> Environment</title>
+
+ <para>
+ In order for a <command>chroot</command> environment
+ to
+ work properly in a particular directory
+ (for example, <filename>/var/named</filename>),
+ you will need to set up an environment that includes everything
+ <acronym>BIND</acronym> needs to run.
+ From <acronym>BIND</acronym>'s point of view, <filename>/var/named</filename> is
+ the root of the filesystem. You will need to adjust the values of
+ options like
+ like <command>directory</command> and <command>pid-file</command> to account
+ for this.
+ </para>
+ <para>
+ Unlike with earlier versions of BIND, you typically will
+ <emphasis>not</emphasis> need to compile <command>named</command>
+ statically nor install shared libraries under the new root.
+ However, depending on your operating system, you may need
+ to set up things like
+ <filename>/dev/zero</filename>,
+ <filename>/dev/random</filename>,
+ <filename>/dev/log</filename>, and
+ <filename>/etc/localtime</filename>.
+ </para>
+ </sect2>
+
+ <sect2>
+ <title>Using the <command>setuid</command> Function</title>
+
+ <para>
+ Prior to running the <command>named</command> daemon,
+ use
+ the <command>touch</command> utility (to change file
+ access and
+ modification times) or the <command>chown</command>
+ utility (to
+ set the user id and/or group id) on files
+ to which you want <acronym>BIND</acronym>
+ to write.
+ </para>
<note>
Note that if the <command>named</command> daemon is running as an
- unprivileged user, it will not be able to bind to new restricted
- ports if the server is reloaded.
+ unprivileged user, it will not be able to bind to new restricted
+ ports if the server is reloaded.
</note>
- </sect2>
+ </sect2>
</sect1>
<sect1 id="dynamic_update_security">
- <title>Dynamic Update Security</title>
-
- Access to the dynamic
- update facility should be strictly limited. In earlier versions of
-
<acronym>BIND</acronym>, the only way to do this was
- based on the IP
- address of the host requesting the update, by listing an IP address
- or
- network prefix in the <command>allow-update</command>
- zone option.
- This method is insecure since the source address of the update UDP
- packet
- is easily forged. Also note that if the IP addresses allowed by the
- <command>allow-update</command> option include the
- address of a slave
- server which performs forwarding of dynamic updates, the master can
- be
- trivially attacked by sending the update to the slave, which will
- forward it to the master with its own source IP address causing the
- master to approve it without question.
- </para>
-
- For these reasons, we strongly recommend that updates be
- cryptographically authenticated by means of transaction signatures
- (TSIG). That is, the <command>allow-update</command>
- option should
- list only TSIG key names, not IP addresses or network
- prefixes. Alternatively, the new <command>update-policy</command>
- option can be used.
- </para>
-
- Some sites choose to keep all dynamically-updated DNS data
- in a subdomain and delegate that subdomain to a separate zone. This
- way, the top-level zone containing critical data such as the IP
- addresses
- of public web and mail servers need not allow dynamic update at
- all.
- </para>
+ <title>Dynamic Update Security</title>
+
+ <para>
+ Access to the dynamic
+ update facility should be strictly limited. In earlier versions of
+ <acronym>BIND</acronym>, the only way to do this was
+ based on the IP
+ address of the host requesting the update, by listing an IP address
+ or
+ network prefix in the <command>allow-update</command>
+ zone option.
+ This method is insecure since the source address of the update UDP
+ packet
+ is easily forged. Also note that if the IP addresses allowed by the
+ <command>allow-update</command> option include the
+ address of a slave
+ server which performs forwarding of dynamic updates, the master can
+ be
+ trivially attacked by sending the update to the slave, which will
+ forward it to the master with its own source IP address causing the
+ master to approve it without question.
+ </para>
+
+ <para>
+ For these reasons, we strongly recommend that updates be
+ cryptographically authenticated by means of transaction signatures
+ (TSIG). That is, the <command>allow-update</command>
+ option should
+ list only TSIG key names, not IP addresses or network
+ prefixes. Alternatively, the new <command>update-policy</command>
+ option can be used.
+ </para>
+
+ <para>
+ Some sites choose to keep all dynamically-updated DNS data
+ in a subdomain and delegate that subdomain to a separate zone. This
+ way, the top-level zone containing critical data such as the IP
+ addresses
+ of public web and mail servers need not allow dynamic update at
+ all.
+ </para>
</sect1>
</chapter>
<chapter id="Bv9ARM.ch08">
<title>Troubleshooting</title>
<sect1>
- <title>Common Problems</title>
- <sect2>
- <title>It's not working; how can I figure out what's wrong?</title>
-
- The best solution to solving installation and
- configuration issues is to take preventative measures by setting
- up logging files beforehand. The log files provide a
- source of hints and information that can be used to figure out
- what went wrong and how to fix the problem.
- </para>
-
- </sect2>
+ <title>Common Problems</title>
+ <sect2>
+ <title>It's not working; how can I figure out what's wrong?</title>
+
+ <para>
+ The best solution to solving installation and
+ configuration issues is to take preventative measures by setting
+ up logging files beforehand. The log files provide a
+ source of hints and information that can be used to figure out
+ what went wrong and how to fix the problem.
+ </para>
+
+ </sect2>
</sect1>
<sect1>
- <title>Incrementing and Changing the Serial Number</title>
+ <title>Incrementing and Changing the Serial Number</title>
<para>
Zone serial numbers are just numbers — they aren't
server will attempt to update its copy of the zone.
</para>
- Setting the serial number to a lower number on the master
- server than the slave server means that the slave will not perform
- updates to its copy of the zone.
- </para>
+ <para>
+ Setting the serial number to a lower number on the master
+ server than the slave server means that the slave will not perform
+ updates to its copy of the zone.
+ </para>
- The solution to this is to add 2147483647 (2^31-1) to the
- number, reload the zone and make sure all slaves have updated to
- the new zone serial number, then reset the number to what you want
- it to be, and reload the zone again.
- </para>
+ <para>
+ The solution to this is to add 2147483647 (2^31-1) to the
+ number, reload the zone and make sure all slaves have updated to
+ the new zone serial number, then reset the number to what you want
+ it to be, and reload the zone again.
+ </para>
</sect1>
<sect1>
- <title>Where Can I Get Help?</title>
-
- The Internet Systems Consortium
-
(<acronym>ISC</acronym>) offers a wide range
-
of support and service agreements for <acronym>BIND</acronym> and <acronym>DHCP</acronym> servers. Four
- levels of premium support are available and each level includes
-
support for all <acronym>ISC</acronym> programs,
- significant discounts on products
- and training, and a recognized priority on bug fixes and
-
non-funded feature requests. In addition, <acronym>ISC</acronym> offers a standard
- support agreement package which includes services ranging from bug
- fix announcements to remote support. It also includes training in
-
<acronym>BIND</acronym> and <acronym>DHCP</acronym>.
- </para>
-
- To discuss arrangements for support, contact
-
<ulink url="mailto:info@isc.org">info@isc.org</ulink> or visit the
-
<acronym>ISC</acronym> web page at
+ <title>Where Can I Get Help?</title>
+
+ <para>
+ The Internet Systems Consortium
+ (<acronym>ISC</acronym>) offers a wide range
+ of support and service agreements for <acronym>BIND</acronym> and <acronym>DHCP</acronym> servers. Four
+ levels of premium support are available and each level includes
+ support for all <acronym>ISC</acronym> programs,
+ significant discounts on products
+ and training, and a recognized priority on bug fixes and
+ non-funded feature requests. In addition, <acronym>ISC</acronym> offers a standard
+ support agreement package which includes services ranging from bug
+ fix announcements to remote support. It also includes training in
+ <acronym>BIND</acronym> and <acronym>DHCP</acronym>.
+ </para>
+
+ <para>
+ To discuss arrangements for support, contact
+ <ulink url="mailto:info@isc.org">info@isc.org</ulink> or visit the
+ <acronym>ISC</acronym> web page at
<ulink url="http://www.isc.org/services/support/"
- >http://www.isc.org/services/support/</ulink>
- to read more.
- </para>
+ >http://www.isc.org/services/support/</ulink>
+ to read more.
+ </para>
</sect1>
</chapter>
<appendix id="Bv9ARM.ch09">
<title>Appendices</title>
<sect1>
- <title>Acknowledgments</title>
- <sect2 id="historical_dns_information">
-
<title>A Brief History of the <acronym>DNS</acronym> and <acronym>BIND</acronym></title>
-
- Although the "official" beginning of the Domain Name
- System occurred in 1984 with the publication of RFC 920, the
- core of the new system was described in 1983 in RFCs 882 and
- 883. From 1984 to 1987, the ARPAnet (the precursor to today's
- Internet) became a testbed of experimentation for developing the
- new naming/addressing scheme in a rapidly expanding,
- operational network environment. New RFCs were written and
- published in 1987 that modified the original documents to
- incorporate improvements based on the working model. RFC 1034,
- "Domain Names-Concepts and Facilities", and RFC 1035, "Domain
- Names-Implementation and Specification" were published and
-
became the standards upon which all <acronym>DNS</acronym> implementations are
- built.
- </para>
-
- The first working domain name server, called "Jeeves", was
- written in 1983-84 by Paul Mockapetris for operation on DEC
- Tops-20
- machines located at the University of Southern California's
- Information
- Sciences Institute (USC-ISI) and SRI International's Network
- Information
-
Center (SRI-NIC). A <acronym>DNS</acronym> server for
- Unix machines, the Berkeley Internet
-
Name Domain (<acronym>BIND</acronym>) package, was
- written soon after by a group of
- graduate students at the University of California at Berkeley
- under
- a grant from the US Defense Advanced Research Projects
- Administration
- (DARPA).
- </para>
+ <title>Acknowledgments</title>
+ <sect2 id="historical_dns_information">
+ <title>A Brief History of the <acronym>DNS</acronym> and <acronym>BIND</acronym></title>
+
+ <para>
+ Although the "official" beginning of the Domain Name
+ System occurred in 1984 with the publication of RFC 920, the
+ core of the new system was described in 1983 in RFCs 882 and
+ 883. From 1984 to 1987, the ARPAnet (the precursor to today's
+ Internet) became a testbed of experimentation for developing the
+ new naming/addressing scheme in a rapidly expanding,
+ operational network environment. New RFCs were written and
+ published in 1987 that modified the original documents to
+ incorporate improvements based on the working model. RFC 1034,
+ "Domain Names-Concepts and Facilities", and RFC 1035, "Domain
+ Names-Implementation and Specification" were published and
+ became the standards upon which all <acronym>DNS</acronym> implementations are
+ built.
+ </para>
+
+ <para>
+ The first working domain name server, called "Jeeves", was
+ written in 1983-84 by Paul Mockapetris for operation on DEC
+ Tops-20
+ machines located at the University of Southern California's
+ Information
+ Sciences Institute (USC-ISI) and SRI International's Network
+ Information
+ Center (SRI-NIC). A <acronym>DNS</acronym> server for
+ Unix machines, the Berkeley Internet
+ Name Domain (<acronym>BIND</acronym>) package, was
+ written soon after by a group of
+ graduate students at the University of California at Berkeley
+ under
+ a grant from the US Defense Advanced Research Projects
+ Administration
+ (DARPA).
+ </para>
+ <para>
Versions of <acronym>BIND</acronym> through
- 4.8.3 were maintained by the Computer
- Systems Research Group (CSRG) at UC Berkeley. Douglas Terry, Mark
-
Painter, David Riggle and Songnian Zhou made up the initial <acronym>BIND</acronym>
- project team. After that, additional work on the software package
- was done by Ralph Campbell. Kevin Dunlap, a Digital Equipment
- Corporation
-
employee on loan to the CSRG, worked on <acronym>BIND</acronym> for 2 years, from 1985
-
to 1987. Many other people also contributed to <acronym>BIND</acronym> development
- during that time: Doug Kingston, Craig Partridge, Smoot
- Carl-Mitchell,
-
Mike Muuss, Jim Bloom and Mike Schwartz. <acronym>BIND</acronym> maintenance was subsequently
- handled by Mike Karels and Øivind Kure.
- </para>
-
<acronym>BIND</acronym> versions 4.9 and 4.9.1 were
- released by Digital Equipment
- Corporation (now Compaq Computer Corporation). Paul Vixie, then
-
a DEC employee, became <acronym>BIND</acronym>'s
- primary caretaker. He was assisted
- by Phil Almquist, Robert Elz, Alan Barrett, Paul Albitz, Bryan
- Beecher, Andrew
- Partan, Andy Cherenson, Tom Limoncelli, Berthold Paffrath, Fuat
- Baran, Anant Kumar, Art Harkin, Win Treese, Don Lewis, Christophe
- Wolfhugel, and others.
- </para>
-
In 1994, <acronym>BIND</acronym> version 4.9.2 was sponsored by
- Vixie Enterprises. Paul
-
Vixie became <acronym>BIND</acronym>'s principal
- architect/programmer.
- </para>
-
<acronym>BIND</acronym> versions from 4.9.3 onward
- have been developed and maintained
- by the Internet Systems Consortium and its predecessor,
- the Internet Software Consortium, with support being provided
- by ISC's sponsors.
- </para>
+ 4.8.3 were maintained by the Computer
+ Systems Research Group (CSRG) at UC Berkeley. Douglas Terry, Mark
+ Painter, David Riggle and Songnian Zhou made up the initial <acronym>BIND</acronym>
+ project team. After that, additional work on the software package
+ was done by Ralph Campbell. Kevin Dunlap, a Digital Equipment
+ Corporation
+ employee on loan to the CSRG, worked on <acronym>BIND</acronym> for 2 years, from 1985
+ to 1987. Many other people also contributed to <acronym>BIND</acronym> development
+ during that time: Doug Kingston, Craig Partridge, Smoot
+ Carl-Mitchell,
+ Mike Muuss, Jim Bloom and Mike Schwartz. <acronym>BIND</acronym> maintenance was subsequently
+ handled by Mike Karels and Øivind Kure.
+ </para>
+ <para>
+ <acronym>BIND</acronym> versions 4.9 and 4.9.1 were
+ released by Digital Equipment
+ Corporation (now Compaq Computer Corporation). Paul Vixie, then
+ a DEC employee, became <acronym>BIND</acronym>'s
+ primary caretaker. He was assisted
+ by Phil Almquist, Robert Elz, Alan Barrett, Paul Albitz, Bryan
+ Beecher, Andrew
+ Partan, Andy Cherenson, Tom Limoncelli, Berthold Paffrath, Fuat
+ Baran, Anant Kumar, Art Harkin, Win Treese, Don Lewis, Christophe
+ Wolfhugel, and others.
+ </para>
+ <para>
+ In 1994, <acronym>BIND</acronym> version 4.9.2 was sponsored by
+ Vixie Enterprises. Paul
+ Vixie became <acronym>BIND</acronym>'s principal
+ architect/programmer.
+ </para>
+ <para>
+ <acronym>BIND</acronym> versions from 4.9.3 onward
+ have been developed and maintained
+ by the Internet Systems Consortium and its predecessor,
+ the Internet Software Consortium, with support being provided
+ by ISC's sponsors.
+ </para>
<para>
As co-architects/programmers, Bob Halley and
- Paul Vixie released the first production-ready version of
+ Paul Vixie released the first production-ready version of
<acronym>BIND</acronym> version 8 in May 1997.
- </para>
+ </para>
<para>
BIND version 9 was released in September 2000 and is a
major rewrite of nearly all aspects of the underlying
BIND architecture.
- </para>
+ </para>
+ <para>
BIND versions 4 and 8 are officially deprecated.
No additional development is done
on BIND version 4 or BIND version 8.
- </para>
-
<acronym>BIND</acronym> development work is made
- possible today by the sponsorship
- of several corporations, and by the tireless work efforts of
- numerous individuals.
- </para>
- </sect2>
+ </para>
+ <para>
+ <acronym>BIND</acronym> development work is made
+ possible today by the sponsorship
+ of several corporations, and by the tireless work efforts of
+ numerous individuals.
+ </para>
+ </sect2>
</sect1>
<sect1>
-
<title>General <acronym>DNS</acronym> Reference Information</title>
- <sect2 id="ipv6addresses">
- <title>IPv6 addresses (AAAA)</title>
- IPv6 addresses are 128-bit identifiers for interfaces and
-
sets of interfaces which were introduced in the <acronym>DNS</acronym> to facilitate
- scalable Internet routing. There are three types of addresses: <emphasis>Unicast</emphasis>,
- an identifier for a single interface;
- <emphasis>Anycast</emphasis>,
- an identifier for a set of interfaces; and <emphasis>Multicast</emphasis>,
- an identifier for a set of interfaces. Here we describe the global
- Unicast address scheme. For more information, see RFC 3587,
+ <title>General <acronym>DNS</acronym> Reference Information</title>
+ <sect2 id="ipv6addresses">
+ <title>IPv6 addresses (AAAA)</title>
+ <para>
+ IPv6 addresses are 128-bit identifiers for interfaces and
+ sets of interfaces which were introduced in the <acronym>DNS</acronym> to facilitate
+ scalable Internet routing. There are three types of addresses: <emphasis>Unicast</emphasis>,
+ an identifier for a single interface;
+ <emphasis>Anycast</emphasis>,
+ an identifier for a set of interfaces; and <emphasis>Multicast</emphasis>,
+ an identifier for a set of interfaces. Here we describe the global
+ Unicast address scheme. For more information, see RFC 3587,
"Global Unicast Address Format."
- </para>
+ </para>
+ <para>
IPv6 unicast addresses consist of a
<emphasis>global routing prefix</emphasis>, a
<emphasis>subnet identifier</emphasis>, and an
<emphasis>interface identifier</emphasis>.
- </para>
- The global routing prefix is provided by the
- upstream provider or ISP, and (roughly) corresponds to the
+ </para>
+ <para>
+ The global routing prefix is provided by the
+ upstream provider or ISP, and (roughly) corresponds to the
IPv4 <emphasis>network</emphasis> section
- of the address range.
+ of the address range.
The subnet identifier is for local subnetting, much the
- same as subnetting an
- IPv4 /16 network into /24 subnets.
+ same as subnetting an
+ IPv4 /16 network into /24 subnets.
The interface identifier is the address of an individual
- interface on a given network; in IPv6, addresses belong to
- interfaces rather than to machines.
- </para>
- The subnetting capability of IPv6 is much more flexible than
- that of IPv4: subnetting can be carried out on bit boundaries,
- in much the same way as Classless InterDomain Routing
- (CIDR), and the DNS PTR representation ("nibble" format)
- makes setting up reverse zones easier.
- </para>
- The Interface Identifier must be unique on the local link,
- and is usually generated automatically by the IPv6
- implementation, although it is usually possible to
- override the default setting if necessary. A typical IPv6
- address might look like:
+ interface on a given network; in IPv6, addresses belong to
+ interfaces rather than to machines.
+ </para>
+ <para>
+ The subnetting capability of IPv6 is much more flexible than
+ that of IPv4: subnetting can be carried out on bit boundaries,
+ in much the same way as Classless InterDomain Routing
+ (CIDR), and the DNS PTR representation ("nibble" format)
+ makes setting up reverse zones easier.
+ </para>
+ <para>
+ The Interface Identifier must be unique on the local link,
+ and is usually generated automatically by the IPv6
+ implementation, although it is usually possible to
+ override the default setting if necessary. A typical IPv6
+ address might look like:
<command>2001:db8:201:9:a00:20ff:fe81:2b32</command>
</para>
- IPv6 address specifications often contain long strings
- of zeros, so the architects have included a shorthand for
- specifying
- them. The double colon (`::') indicates the longest possible
- string
- of zeros that can fit, and can be used only once in an address.
- </para>
- </sect2>
+ <para>
+ IPv6 address specifications often contain long strings
+ of zeros, so the architects have included a shorthand for
+ specifying
+ them. The double colon (`::') indicates the longest possible
+ string
+ of zeros that can fit, and can be used only once in an address.
+ </para>
+ </sect2>
</sect1>
<sect1 id="bibliography">
- <title>Bibliography (and Suggested Reading)</title>
- <sect2 id="rfcs">
- <title>Request for Comments (RFCs)</title>
- Specification documents for the Internet protocol suite, including
-
the <acronym>DNS</acronym>, are published as part of
- the Request for Comments (RFCs)
- series of technical notes. The standards themselves are defined
- by the Internet Engineering Task Force (IETF) and the Internet
- Engineering Steering Group (IESG). RFCs can be obtained online via FTP at:
- </para>
- <para>
-
<ulink url="ftp://www.isi.edu/in-notes/">
+ <title>Bibliography (and Suggested Reading)</title>
+ <sect2 id="rfcs">
+ <title>Request for Comments (RFCs)</title>
+ <para>
+ Specification documents for the Internet protocol suite, including
+ the <acronym>DNS</acronym>, are published as part of
+ the Request for Comments (RFCs)
+ series of technical notes. The standards themselves are defined
+ by the Internet Engineering Task Force (IETF) and the Internet
+ Engineering Steering Group (IESG). RFCs can be obtained online via FTP at:
+ </para>
+ <para>
+ <ulink url="ftp://www.isi.edu/in-notes/">
ftp://www.isi.edu/in-notes/RFC<replaceable>xxxx</replaceable>.txt
</ulink>
</para>
<para>
(where <replaceable>xxxx</replaceable> is
- the number of the RFC). RFCs are also available via the Web at:
- </para>
- <para>
- <ulink url="http://www.ietf.org/rfc/"
- >http://www.ietf.org/rfc/</ulink>.
- </para>
- <bibliography>
- <bibliodiv>
- <!-- one of (BIBLIOENTRY BIBLIOMIXED) -->
- <title>Standards</title>
- <biblioentry>
- <abbrev>RFC974</abbrev>
- <author>
- <surname>Partridge</surname>
- <firstname>C.</firstname>
- </author>
- <title>Mail Routing and the Domain System</title>
- <pubdate>January 1986</pubdate>
- </biblioentry>
- <biblioentry>
- <abbrev>RFC1034</abbrev>
- <author>
- <surname>Mockapetris</surname>
- <firstname>P.V.</firstname>
- </author>
- <title>Domain Names — Concepts and Facilities</title>
- <pubdate>November 1987</pubdate>
- </biblioentry>
- <biblioentry>
- <abbrev>RFC1035</abbrev>
- <author>
- <surname>Mockapetris</surname>
- <firstname>P. V.</firstname>
- </author> <title>Domain Names — Implementation and
- Specification</title>
- <pubdate>November 1987</pubdate>
- </biblioentry>
- </bibliodiv>
- <bibliodiv id="proposed_standards" xreflabel="Proposed Standards">
-
- <title>Proposed Standards</title>
- <!-- one of (BIBLIOENTRY BIBLIOMIXED) -->
- <biblioentry>
- <abbrev>RFC2181</abbrev>
- <author>
- <surname>Elz</surname>
- <firstname>R., R. Bush</firstname>
- </author>
- <title>Clarifications to the <acronym>DNS</acronym>
- Specification</title>
- <pubdate>July 1997</pubdate>
- </biblioentry>
- <biblioentry>
- <abbrev>RFC2308</abbrev>
- <author>
- <surname>Andrews</surname>
- <firstname>M.</firstname>
- </author>
- <title>Negative Caching of <acronym>DNS</acronym>
- Queries</title>
- <pubdate>March 1998</pubdate>
- </biblioentry>
- <biblioentry>
- <abbrev>RFC1995</abbrev>
- <author>
- <surname>Ohta</surname>
- <firstname>M.</firstname>
- </author>
- <title>Incremental Zone Transfer in <acronym>DNS</acronym></title>
- <pubdate>August 1996</pubdate>
- </biblioentry>
- <biblioentry>
- <abbrev>RFC1996</abbrev>
- <author>
- <surname>Vixie</surname>
- <firstname>P.</firstname>
- </author>
- <title>A Mechanism for Prompt Notification of Zone Changes</title>
- <pubdate>August 1996</pubdate>
- </biblioentry>
- <biblioentry>
- <abbrev>RFC2136</abbrev>
- <authorgroup>
- <author>
- <surname>Vixie</surname>
- <firstname>P.</firstname>
- </author>
- <author>
- <firstname>S.</firstname>
- <surname>Thomson</surname>
- </author>
- <author>
- <firstname>Y.</firstname>
- <surname>Rekhter</surname>
- </author>
- <author>
- <firstname>J.</firstname>
- <surname>Bound</surname>
- </author>
- </authorgroup>
- <title>Dynamic Updates in the Domain Name System</title>
- <pubdate>April 1997</pubdate>
- </biblioentry>
+ the number of the RFC). RFCs are also available via the Web at:
+ </para>
+ <para>
+ <ulink url="http://www.ietf.org/rfc/"
+ >http://www.ietf.org/rfc/</ulink>.
+ </para>
+ <bibliography>
+ <bibliodiv>
+ <!-- one of (BIBLIOENTRY BIBLIOMIXED) -->
+ <title>Standards</title>
+ <biblioentry>
+ <abbrev>RFC974</abbrev>
+ <author>
+ <surname>Partridge</surname>
+ <firstname>C.</firstname>
+ </author>
+ <title>Mail Routing and the Domain System</title>
+ <pubdate>January 1986</pubdate>
+ </biblioentry>
+ <biblioentry>
+ <abbrev>RFC1034</abbrev>
+ <author>
+ <surname>Mockapetris</surname>
+ <firstname>P.V.</firstname>
+ </author>
+ <title>Domain Names — Concepts and Facilities</title>
+ <pubdate>November 1987</pubdate>
+ </biblioentry>
+ <biblioentry>
+ <abbrev>RFC1035</abbrev>
+ <author>
+ <surname>Mockapetris</surname>
+ <firstname>P. V.</firstname>
+ </author> <title>Domain Names — Implementation and
+ Specification</title>
+ <pubdate>November 1987</pubdate>
+ </biblioentry>
+ </bibliodiv>
+ <bibliodiv id="proposed_standards" xreflabel="Proposed Standards">
+
+ <title>Proposed Standards</title>
+ <!-- one of (BIBLIOENTRY BIBLIOMIXED) -->
+ <biblioentry>
+ <abbrev>RFC2181</abbrev>
+ <author>
+ <surname>Elz</surname>
+ <firstname>R., R. Bush</firstname>
+ </author>
+ <title>Clarifications to the <acronym>DNS</acronym>
+ Specification</title>
+ <pubdate>July 1997</pubdate>
+ </biblioentry>
+ <biblioentry>
+ <abbrev>RFC2308</abbrev>
+ <author>
+ <surname>Andrews</surname>
+ <firstname>M.</firstname>
+ </author>
+ <title>Negative Caching of <acronym>DNS</acronym>
+ Queries</title>
+ <pubdate>March 1998</pubdate>
+ </biblioentry>
+ <biblioentry>
+ <abbrev>RFC1995</abbrev>
+ <author>
+ <surname>Ohta</surname>
+ <firstname>M.</firstname>
+ </author>
+ <title>Incremental Zone Transfer in <acronym>DNS</acronym></title>
+ <pubdate>August 1996</pubdate>
+ </biblioentry>
+ <biblioentry>
+ <abbrev>RFC1996</abbrev>
+ <author>
+ <surname>Vixie</surname>
+ <firstname>P.</firstname>
+ </author>
+ <title>A Mechanism for Prompt Notification of Zone Changes</title>
+ <pubdate>August 1996</pubdate>
+ </biblioentry>
+ <biblioentry>
+ <abbrev>RFC2136</abbrev>
+ <authorgroup>
+ <author>
+ <surname>Vixie</surname>
+ <firstname>P.</firstname>
+ </author>
+ <author>
+ <firstname>S.</firstname>
+ <surname>Thomson</surname>
+ </author>
+ <author>
+ <firstname>Y.</firstname>
+ <surname>Rekhter</surname>
+ </author>
+ <author>
+ <firstname>J.</firstname>
+ <surname>Bound</surname>
+ </author>
+ </authorgroup>
+ <title>Dynamic Updates in the Domain Name System</title>
+ <pubdate>April 1997</pubdate>
+ </biblioentry>
+ <biblioentry>
+ <abbrev>RFC2671</abbrev>
+ <authorgroup>
+ <author>
+ <firstname>P.</firstname>
+ <surname>Vixie</surname>
+ </author>
+ </authorgroup>
+ <title>Extension Mechanisms for DNS (EDNS0)</title>
+ <pubdate>August 1997</pubdate>
+ </biblioentry>
+ <biblioentry>
+ <abbrev>RFC2672</abbrev>
+ <authorgroup>
+ <author>
+ <firstname>M.</firstname>
+ <surname>Crawford</surname>
+ </author>
+ </authorgroup>
+ <title>Non-Terminal DNS Name Redirection</title>
+ <pubdate>August 1999</pubdate>
+ </biblioentry>
+ <biblioentry>
+ <abbrev>RFC2845</abbrev>
+ <authorgroup>
+ <author>
+ <surname>Vixie</surname>
+ <firstname>P.</firstname>
+ </author>
+ <author>
+ <firstname>O.</firstname>
+ <surname>Gudmundsson</surname>
+ </author>
+ <author>
+ <firstname>D.</firstname>
+ <surname>Eastlake</surname>
+ <lineage>3rd</lineage>
+ </author>
+ <author>
+ <firstname>B.</firstname>
+ <surname>Wellington</surname>
+ </author>
+ </authorgroup>
+ <title>Secret Key Transaction Authentication for <acronym>DNS</acronym> (TSIG)</title>
+ <pubdate>May 2000</pubdate>
+ </biblioentry>
+ <biblioentry>
+ <abbrev>RFC2930</abbrev>
+ <authorgroup>
+ <author>
+ <firstname>D.</firstname>
+ <surname>Eastlake</surname>
+ <lineage>3rd</lineage>
+ </author>
+ </authorgroup>
+ <title>Secret Key Establishment for DNS (TKEY RR)</title>
+ <pubdate>September 2000</pubdate>
+ </biblioentry>
+ <biblioentry>
+ <abbrev>RFC2931</abbrev>
+ <authorgroup>
+ <author>
+ <firstname>D.</firstname>
+ <surname>Eastlake</surname>
+ <lineage>3rd</lineage>
+ </author>
+ </authorgroup>
+ <title>DNS Request and Transaction Signatures (SIG(0)s)</title>
+ <pubdate>September 2000</pubdate>
+ </biblioentry>
+ <biblioentry>
+ <abbrev>RFC3007</abbrev>
+ <authorgroup>
+ <author>
+ <firstname>B.</firstname>
+ <surname>Wellington</surname>
+ </author>
+ </authorgroup>
+ <title>Secure Domain Name System (DNS) Dynamic Update</title>
+ <pubdate>November 2000</pubdate>
+ </biblioentry>
+ <biblioentry>
+ <abbrev>RFC3645</abbrev>
+ <authorgroup>
+ <author>
+ <firstname>S.</firstname>
+ <surname>Kwan</surname>
+ </author>
+ <author>
+ <firstname>P.</firstname>
+ <surname>Garg</surname>
+ </author>
+ <author>
+ <firstname>J.</firstname>
+ <surname>Gilroy</surname>
+ </author>
+ <author>
+ <firstname>L.</firstname>
+ <surname>Esibov</surname>
+ </author>
+ <author>
+ <firstname>J.</firstname>
+ <surname>Westhead</surname>
+ </author>
+ <author>
+ <firstname>R.</firstname>
+ <surname>Hall</surname>
+ </author>
+ </authorgroup>
+ <title>Generic Security Service Algorithm for Secret
+ Key Transaction Authentication for DNS
+ (GSS-TSIG)</title>
+ <pubdate>October 2003</pubdate>
+ </biblioentry>
+ </bibliodiv>
+ <bibliodiv>
+ <title><acronym>DNS</acronym> Security Proposed Standards</title>
+ <biblioentry>
+ <abbrev>RFC3225</abbrev>
+ <authorgroup>
+ <author>
+ <firstname>D.</firstname>
+ <surname>Conrad</surname>
+ </author>
+ </authorgroup>
+ <title>Indicating Resolver Support of DNSSEC</title>
+ <pubdate>December 2001</pubdate>
+ </biblioentry>
+ <biblioentry>
+ <abbrev>RFC3833</abbrev>
+ <authorgroup>
+ <author>
+ <firstname>D.</firstname>
+ <surname>Atkins</surname>
+ </author>
+ <author>
+ <firstname>R.</firstname>
+ <surname>Austein</surname>
+ </author>
+ </authorgroup>
+ <title>Threat Analysis of the Domain Name System (DNS)</title>
+ <pubdate>August 2004</pubdate>
+ </biblioentry>
+ <biblioentry>
+ <abbrev>RFC4033</abbrev>
+ <authorgroup>
+ <author>
+ <firstname>R.</firstname>
+ <surname>Arends</surname>
+ </author>
+ <author>
+ <firstname>R.</firstname>
+ <surname>Austein</surname>
+ </author>
+ <author>
+ <firstname>M.</firstname>
+ <surname>Larson</surname>
+ </author>
+ <author>
+ <firstname>D.</firstname>
+ <surname>Massey</surname>
+ </author>
+ <author>
+ <firstname>S.</firstname>
+ <surname>Rose</surname>
+ </author>
+ </authorgroup>
+ <title>DNS Security Introduction and Requirements</title>
+ <pubdate>March 2005</pubdate>
+ </biblioentry>
+ <biblioentry>
+ <abbrev>RFC4034</abbrev>
+ <authorgroup>
+ <author>
+ <firstname>R.</firstname>
+ <surname>Arends</surname>
+ </author>
+ <author>
+ <firstname>R.</firstname>
+ <surname>Austein</surname>
+ </author>
+ <author>
+ <firstname>M.</firstname>
+ <surname>Larson</surname>
+ </author>
+ <author>
+ <firstname>D.</firstname>
+ <surname>Massey</surname>
+ </author>
+ <author>
+ <firstname>S.</firstname>
+ <surname>Rose</surname>
+ </author>
+ </authorgroup>
+ <title>Resource Records for the DNS Security Extensions</title>
+ <pubdate>March 2005</pubdate>
+ </biblioentry>
+ <biblioentry>
+ <abbrev>RFC4035</abbrev>
+ <authorgroup>
+ <author>
+ <firstname>R.</firstname>
+ <surname>Arends</surname>
+ </author>
+ <author>
+ <firstname>R.</firstname>
+ <surname>Austein</surname>
+ </author>
+ <author>
+ <firstname>M.</firstname>
+ <surname>Larson</surname>
+ </author>
+ <author>
+ <firstname>D.</firstname>
+ <surname>Massey</surname>
+ </author>
+ <author>
+ <firstname>S.</firstname>
+ <surname>Rose</surname>
+ </author>
+ </authorgroup>
+ <title>Protocol Modifications for the DNS
+ Security Extensions</title>
+ <pubdate>March 2005</pubdate>
+ </biblioentry>
+ </bibliodiv>
+ <bibliodiv>
+ <title>Other Important RFCs About <acronym>DNS</acronym>
+ Implementation</title>
+ <biblioentry>
+ <abbrev>RFC1535</abbrev>
+ <author>
+ <surname>Gavron</surname>
+ <firstname>E.</firstname>
+ </author>
+ <title>A Security Problem and Proposed Correction With Widely
+ Deployed <acronym>DNS</acronym> Software.</title>
+ <pubdate>October 1993</pubdate>
+ </biblioentry>
+ <biblioentry>
+ <abbrev>RFC1536</abbrev>
+ <authorgroup>
+ <author>
+ <surname>Kumar</surname>
+ <firstname>A.</firstname>
+ </author>
+ <author>
+ <firstname>J.</firstname>
+ <surname>Postel</surname>
+ </author>
+ <author>
+ <firstname>C.</firstname>
+ <surname>Neuman</surname>
+ </author>
+ <author>
+ <firstname>P.</firstname>
+ <surname>Danzig</surname>
+ </author>
+ <author>
+ <firstname>S.</firstname>
+ <surname>Miller</surname>
+ </author>
+ </authorgroup>
+ <title>Common <acronym>DNS</acronym> Implementation
+ Errors and Suggested Fixes</title>
+ <pubdate>October 1993</pubdate>
+ </biblioentry>
+ <biblioentry>
+ <abbrev>RFC1982</abbrev>
+ <authorgroup>
+ <author>
+ <surname>Elz</surname>
+ <firstname>R.</firstname>
+ </author>
+ <author>
+ <firstname>R.</firstname>
+ <surname>Bush</surname>
+ </author>
+ </authorgroup>
+ <title>Serial Number Arithmetic</title>
+ <pubdate>August 1996</pubdate>
+ </biblioentry>
+ <biblioentry>
+ <abbrev>RFC4074</abbrev>
+ <authorgroup>
+ <author>
+ <surname>Morishita</surname>
+ <firstname>Y.</firstname>
+ </author>
+ <author>
+ <firstname>T.</firstname>
+ <surname>Jinmei</surname>
+ </author>
+ </authorgroup>
+ <title>Common Misbehaviour Against <acronym>DNS</acronym>
+ Queries for IPv6 Addresses</title>
+ <pubdate>May 2005</pubdate>
+ </biblioentry>
+ </bibliodiv>
+ <bibliodiv>
+ <title>Resource Record Types</title>
+ <biblioentry>
+ <abbrev>RFC1183</abbrev>
+ <authorgroup>
+ <author>
+ <surname>Everhart</surname>
+ <firstname>C.F.</firstname>
+ </author>
+ <author>
+ <firstname>L. A.</firstname>
+ <surname>Mamakos</surname>
+ </author>
+ <author>
+ <firstname>R.</firstname>
+ <surname>Ullmann</surname>
+ </author>
+ <author>
+ <firstname>P.</firstname>
+ <surname>Mockapetris</surname>
+ </author>
+ </authorgroup>
+ <title>New <acronym>DNS</acronym> RR Definitions</title>
+ <pubdate>October 1990</pubdate>
+ </biblioentry>
+ <biblioentry>
+ <abbrev>RFC1706</abbrev>
+ <authorgroup>
+ <author>
+ <surname>Manning</surname>
+ <firstname>B.</firstname>
+ </author>
+ <author>
+ <firstname>R.</firstname>
+ <surname>Colella</surname>
+ </author>
+ </authorgroup>
+ <title><acronym>DNS</acronym> NSAP Resource Records</title>
+ <pubdate>October 1994</pubdate>
+ </biblioentry>
+ <biblioentry>
+ <abbrev>RFC2168</abbrev>
+ <authorgroup>
+ <author>
+ <surname>Daniel</surname>
+ <firstname>R.</firstname>
+ </author>
+ <author>
+ <firstname>M.</firstname>
+ <surname>Mealling</surname>
+ </author>
+ </authorgroup>
+ <title>Resolution of Uniform Resource Identifiers using
+ the Domain Name System</title>
+ <pubdate>June 1997</pubdate>
+ </biblioentry>
+ <biblioentry>
+ <abbrev>RFC1876</abbrev>
+ <authorgroup>
+ <author>
+ <surname>Davis</surname>
+ <firstname>C.</firstname>
+ </author>
+ <author>
+ <firstname>P.</firstname>
+ <surname>Vixie</surname>
+ </author>
+ <author>
+ <firstname>T.</firstname>
+ <firstname>Goodwin</firstname>
+ </author>
+ <author>
+ <firstname>I.</firstname>
+ <surname>Dickinson</surname>
+ </author>
+ </authorgroup>
+ <title>A Means for Expressing Location Information in the
+ Domain
+ Name System</title>
+ <pubdate>January 1996</pubdate>
+ </biblioentry>
+ <biblioentry>
+ <abbrev>RFC2052</abbrev>
+ <authorgroup>
+ <author>
+ <surname>Gulbrandsen</surname>
+ <firstname>A.</firstname>
+ </author>
+ <author>
+ <firstname>P.</firstname>
+ <surname>Vixie</surname>
+ </author>
+ </authorgroup>
+ <title>A <acronym>DNS</acronym> RR for Specifying the
+ Location of
+ Services.</title>
+ <pubdate>October 1996</pubdate>
+ </biblioentry>
+ <biblioentry>
+ <abbrev>RFC2163</abbrev>
+ <author>
+ <surname>Allocchio</surname>
+ <firstname>A.</firstname>
+ </author>
+ <title>Using the Internet <acronym>DNS</acronym> to
+ Distribute MIXER
+ Conformant Global Address Mapping</title>
+ <pubdate>January 1998</pubdate>
+ </biblioentry>
+ <biblioentry>
+ <abbrev>RFC2230</abbrev>
+ <author>
+ <surname>Atkinson</surname>
+ <firstname>R.</firstname>
+ </author>
+ <title>Key Exchange Delegation Record for the <acronym>DNS</acronym></title>
+ <pubdate>October 1997</pubdate>
+ </biblioentry>
+ <biblioentry>
+ <abbrev>RFC2536</abbrev>
+ <author>
+ <surname>Eastlake</surname>
+ <firstname>D.</firstname>
+ <lineage>3rd</lineage>
+ </author>
+ <title>DSA KEYs and SIGs in the Domain Name System (DNS)</title>
+ <pubdate>March 1999</pubdate>
+ </biblioentry>
+ <biblioentry>
+ <abbrev>RFC2537</abbrev>
+ <author>
+ <surname>Eastlake</surname>
+ <firstname>D.</firstname>
+ <lineage>3rd</lineage>
+ </author>
+ <title>RSA/MD5 KEYs and SIGs in the Domain Name System (DNS)</title>
+ <pubdate>March 1999</pubdate>
+ </biblioentry>
+ <biblioentry>
+ <abbrev>RFC2538</abbrev>
+ <authorgroup>
+ <author>
+ <surname>Eastlake</surname>
+ <firstname>D.</firstname>
+ <lineage>3rd</lineage>
+ </author>
+ <author>
+ <surname>Gudmundsson</surname>
+ <firstname>O.</firstname>
+ </author>
+ </authorgroup>
+ <title>Storing Certificates in the Domain Name System (DNS)</title>
+ <pubdate>March 1999</pubdate>
+ </biblioentry>
+ <biblioentry>
+ <abbrev>RFC2539</abbrev>
+ <authorgroup>
+ <author>
+ <surname>Eastlake</surname>
+ <firstname>D.</firstname>
+ <lineage>3rd</lineage>
+ </author>
+ </authorgroup>
+ <title>Storage of Diffie-Hellman Keys in the Domain Name System (DNS)</title>
+ <pubdate>March 1999</pubdate>
+ </biblioentry>
+ <biblioentry>
+ <abbrev>RFC2540</abbrev>
+ <authorgroup>
+ <author>
+ <surname>Eastlake</surname>
+ <firstname>D.</firstname>
+ <lineage>3rd</lineage>
+ </author>
+ </authorgroup>
+ <title>Detached Domain Name System (DNS) Information</title>
+ <pubdate>March 1999</pubdate>
+ </biblioentry>
+ <biblioentry>
+ <abbrev>RFC2782</abbrev>
+ <author>
+ <surname>Gulbrandsen</surname>
+ <firstname>A.</firstname>
+ </author>
+ <author>
+ <surname>Vixie</surname>
+ <firstname>P.</firstname>
+ </author>
+ <author>
+ <surname>Esibov</surname>
+ <firstname>L.</firstname>
+ </author>
+ <title>A DNS RR for specifying the location of services (DNS SRV)</title>
+ <pubdate>February 2000</pubdate>
+ </biblioentry>
+ <biblioentry>
+ <abbrev>RFC2915</abbrev>
+ <author>
+ <surname>Mealling</surname>
+ <firstname>M.</firstname>
+ </author>
+ <author>
+ <surname>Daniel</surname>
+ <firstname>R.</firstname>
+ </author>
+ <title>The Naming Authority Pointer (NAPTR) DNS Resource Record</title>
+ <pubdate>September 2000</pubdate>
+ </biblioentry>
+ <biblioentry>
+ <abbrev>RFC3110</abbrev>
+ <author>
+ <surname>Eastlake</surname>
+ <firstname>D.</firstname>
+ <lineage>3rd</lineage>
+ </author>
+ <title>RSA/SHA-1 SIGs and RSA KEYs in the Domain Name System (DNS)</title>
+ <pubdate>May 2001</pubdate>
+ </biblioentry>
+ <biblioentry>
+ <abbrev>RFC3123</abbrev>
+ <author>
+ <surname>Koch</surname>
+ <firstname>P.</firstname>
+ </author>
+ <title>A DNS RR Type for Lists of Address Prefixes (APL RR)</title>
+ <pubdate>June 2001</pubdate>
+ </biblioentry>
+ <biblioentry>
+ <abbrev>RFC3596</abbrev>
+ <authorgroup>
+ <author>
+ <surname>Thomson</surname>
+ <firstname>S.</firstname>
+ </author>
+ <author>
+ <firstname>C.</firstname>
+ <surname>Huitema</surname>
+ </author>
+ <author>
+ <firstname>V.</firstname>
+ <surname>Ksinant</surname>
+ </author>
+ <author>
+ <firstname>M.</firstname>
+ <surname>Souissi</surname>
+ </author>
+ </authorgroup>
+ <title><acronym>DNS</acronym> Extensions to support IP
+ version 6</title>
+ <pubdate>October 2003</pubdate>
+ </biblioentry>
+ <biblioentry>
+ <abbrev>RFC3597</abbrev>
+ <author>
+ <surname>Gustafsson</surname>
+ <firstname>A.</firstname>
+ </author>
+ <title>Handling of Unknown DNS Resource Record (RR) Types</title>
+ <pubdate>September 2003</pubdate>
+ </biblioentry>
+ </bibliodiv>
+ <bibliodiv>
+ <title><acronym>DNS</acronym> and the Internet</title>
+ <biblioentry>
+ <abbrev>RFC1101</abbrev>
+ <author>
+ <surname>Mockapetris</surname>
+ <firstname>P. V.</firstname>
+ </author>
+ <title><acronym>DNS</acronym> Encoding of Network Names
+ and Other Types</title>
+ <pubdate>April 1989</pubdate>
+ </biblioentry>
+ <biblioentry>
+ <abbrev>RFC1123</abbrev>
+ <author>
+ <surname>Braden</surname>
+ <surname>R.</surname>
+ </author>
+ <title>Requirements for Internet Hosts - Application and
+ Support</title>
+ <pubdate>October 1989</pubdate>
+ </biblioentry>
+ <biblioentry>
+ <abbrev>RFC1591</abbrev>
+ <author>
+ <surname>Postel</surname>
+ <firstname>J.</firstname>
+ </author>
+ <title>Domain Name System Structure and Delegation</title>
+ <pubdate>March 1994</pubdate>
+ </biblioentry>
+ <biblioentry>
+ <abbrev>RFC2317</abbrev>
+ <authorgroup>
+ <author>
+ <surname>Eidnes</surname>
+ <firstname>H.</firstname>
+ </author>
+ <author>
+ <firstname>G.</firstname>
+ <surname>de Groot</surname>
+ </author>
+ <author>
+ <firstname>P.</firstname>
+ <surname>Vixie</surname>
+ </author>
+ </authorgroup>
+ <title>Classless IN-ADDR.ARPA Delegation</title>
+ <pubdate>March 1998</pubdate>
+ </biblioentry>
<biblioentry>
- <abbrev>RFC2671</abbrev>
- <authorgroup>
- <author>
- <firstname>P.</firstname>
- <surname>Vixie</surname>
- </author>
- </authorgroup>
- <title>Extension Mechanisms for DNS (EDNS0)</title>
- <pubdate>August 1997</pubdate>
+ <abbrev>RFC2826</abbrev>
+ <authorgroup>
+ <author>
+ <surname>Internet Architecture Board</surname>
+ </author>
+ </authorgroup>
+ <title>IAB Technical Comment on the Unique DNS Root</title>
+ <pubdate>May 2000</pubdate>
</biblioentry>
<biblioentry>
- <abbrev>RFC2672</abbrev>
- <authorgroup>
- <author>
- <firstname>M.</firstname>
- <surname>Crawford</surname>
- </author>
- </authorgroup>
- <title>Non-Terminal DNS Name Redirection</title>
- <pubdate>August 1999</pubdate>
+ <abbrev>RFC2929</abbrev>
+ <authorgroup>
+ <author>
+ <surname>Eastlake</surname>
+ <firstname>D.</firstname>
+ <lineage>3rd</lineage>
+ </author>
+ <author>
+ <surname>Brunner-Williams</surname>
+ <firstname>E.</firstname>
+ </author>
+ <author>
+ <surname>Manning</surname>
+ <firstname>B.</firstname>
+ </author>
+ </authorgroup>
+ <title>Domain Name System (DNS) IANA Considerations</title>
+ <pubdate>September 2000</pubdate>
</biblioentry>
- <biblioentry>
- <abbrev>RFC2845</abbrev>
- <authorgroup>
- <author>
- <surname>Vixie</surname>
- <firstname>P.</firstname>
- </author>
- <author>
- <firstname>O.</firstname>
- <surname>Gudmundsson</surname>
- </author>
- <author>
- <firstname>D.</firstname>
- <surname>Eastlake</surname>
- <lineage>3rd</lineage>
- </author>
- <author>
- <firstname>B.</firstname>
- <surname>Wellington</surname>
- </author>
- </authorgroup>
- <title>Secret Key Transaction Authentication for <acronym>DNS</acronym> (TSIG)</title>
- <pubdate>May 2000</pubdate>
- </biblioentry>
- <biblioentry>
- <abbrev>RFC2930</abbrev>
- <authorgroup>
- <author>
- <firstname>D.</firstname>
- <surname>Eastlake</surname>
- <lineage>3rd</lineage>
- </author>
- </authorgroup>
- <title>Secret Key Establishment for DNS (TKEY RR)</title>
- <pubdate>September 2000</pubdate>
- </biblioentry>
- <biblioentry>
- <abbrev>RFC2931</abbrev>
- <authorgroup>
- <author>
- <firstname>D.</firstname>
- <surname>Eastlake</surname>
- <lineage>3rd</lineage>
- </author>
- </authorgroup>
- <title>DNS Request and Transaction Signatures (SIG(0)s)</title>
- <pubdate>September 2000</pubdate>
- </biblioentry>
- <biblioentry>
- <abbrev>RFC3007</abbrev>
- <authorgroup>
- <author>
- <firstname>B.</firstname>
- <surname>Wellington</surname>
- </author>
- </authorgroup>
- <title>Secure Domain Name System (DNS) Dynamic Update</title>
- <pubdate>November 2000</pubdate>
- </biblioentry>
- <biblioentry>
- <abbrev>RFC3645</abbrev>
- <authorgroup>
- <author>
- <firstname>S.</firstname>
- <surname>Kwan</surname>
- </author>
- <author>
- <firstname>P.</firstname>
- <surname>Garg</surname>
- </author>
- <author>
- <firstname>J.</firstname>
- <surname>Gilroy</surname>
- </author>
- <author>
- <firstname>L.</firstname>
- <surname>Esibov</surname>
- </author>
- <author>
- <firstname>J.</firstname>
- <surname>Westhead</surname>
- </author>
- <author>
- <firstname>R.</firstname>
- <surname>Hall</surname>
- </author>
- </authorgroup>
- <title>Generic Security Service Algorithm for Secret
- Key Transaction Authentication for DNS
- (GSS-TSIG)</title>
- <pubdate>October 2003</pubdate>
- </biblioentry>
- </bibliodiv>
+ </bibliodiv>
<bibliodiv>
- <title><acronym>DNS</acronym> Security Proposed Standards</title>
+ <title><acronym>DNS</acronym> Operations</title>
<biblioentry>
- <abbrev>RFC3225</abbrev>
- <authorgroup>
+ <abbrev>RFC1033</abbrev>
+ <author>
+ <surname>Lottor</surname>
+ <firstname>M.</firstname>
+ </author>
+ <title>Domain administrators operations guide.</title>
+ <pubdate>November 1987</pubdate>
+ </biblioentry>
+ <biblioentry>
+ <abbrev>RFC1537</abbrev>
+ <author>
+ <surname>Beertema</surname>
+ <firstname>P.</firstname>
+ </author>
+ <title>Common <acronym>DNS</acronym> Data File
+ Configuration Errors</title>
+ <pubdate>October 1993</pubdate>
+ </biblioentry>
+ <biblioentry>
+ <abbrev>RFC1912</abbrev>
+ <author>
+ <surname>Barr</surname>
+ <firstname>D.</firstname>
+ </author>
+ <title>Common <acronym>DNS</acronym> Operational and
+ Configuration Errors</title>
+ <pubdate>February 1996</pubdate>
+ </biblioentry>
+ <biblioentry>
+ <abbrev>RFC2010</abbrev>
+ <authorgroup>
<author>
- <firstname>D.</firstname>
- <surname>Conrad</surname>
+ <surname>Manning</surname>
+ <firstname>B.</firstname>
</author>
- </authorgroup>
- <title>Indicating Resolver Support of DNSSEC</title>
- <pubdate>December 2001</pubdate>
+ <author>
+ <firstname>P.</firstname>
+ <surname>Vixie</surname>
+ </author>
+ </authorgroup>
+ <title>Operational Criteria for Root Name Servers.</title>
+ <pubdate>October 1996</pubdate>
</biblioentry>
<biblioentry>
- <abbrev>RFC3833</abbrev>
- <authorgroup>
+ <abbrev>RFC2219</abbrev>
+ <authorgroup>
<author>
- <firstname>D.</firstname>
- <surname>Atkins</surname>
+ <surname>Hamilton</surname>
+ <firstname>M.</firstname>
</author>
<author>
<firstname>R.</firstname>
- <surname>Austein</surname>
+ <surname>Wright</surname>
</author>
</authorgroup>
- <title>Threat Analysis of the Domain Name System (DNS)</title>
- <pubdate>August 2004</pubdate>
+ <title>Use of <acronym>DNS</acronym> Aliases for
+ Network Services.</title>
+ <pubdate>October 1997</pubdate>
</biblioentry>
+ </bibliodiv>
+ <bibliodiv>
+ <title>Internationalized Domain Names</title>
<biblioentry>
- <abbrev>RFC4033</abbrev>
- <authorgroup>
+ <abbrev>RFC2825</abbrev>
+ <authorgroup>
<author>
- <firstname>R.</firstname>
- <surname>Arends</surname>
+ <surname>IAB</surname>
</author>
<author>
+ <surname>Daigle</surname>
<firstname>R.</firstname>
- <surname>Austein</surname>
+ </author>
+ </authorgroup>
+ <title>A Tangled Web: Issues of I18N, Domain Names,
+ and the Other Internet protocols</title>
+ <pubdate>May 2000</pubdate>
+ </biblioentry>
+ <biblioentry>
+ <abbrev>RFC3490</abbrev>
+ <authorgroup>
+ <author>
+ <surname>Faltstrom</surname>
+ <firstname>P.</firstname>
+ </author>
+ <author>
+ <surname>Hoffman</surname>
+ <firstname>P.</firstname>
+ </author>
+ <author>
+ <surname>Costello</surname>
+ <firstname>A.</firstname>
+ </author>
+ </authorgroup>
+ <title>Internationalizing Domain Names in Applications (IDNA)</title>
+ <pubdate>March 2003</pubdate>
+ </biblioentry>
+ <biblioentry>
+ <abbrev>RFC3491</abbrev>
+ <authorgroup>
+ <author>
+ <surname>Hoffman</surname>
+ <firstname>P.</firstname>
</author>
<author>
+ <surname>Blanchet</surname>
<firstname>M.</firstname>
- <surname>Larson</surname>
</author>
+ </authorgroup>
+ <title>Nameprep: A Stringprep Profile for Internationalized Domain Names</title>
+ <pubdate>March 2003</pubdate>
+ </biblioentry>
+ <biblioentry>
+ <abbrev>RFC3492</abbrev>
+ <authorgroup>
<author>
- <firstname>D.</firstname>
- <surname>Massey</surname>
+ <surname>Costello</surname>
+ <firstname>A.</firstname>
+ </author>
+ </authorgroup>
+ <title>Punycode: A Bootstring encoding of Unicode
+ for Internationalized Domain Names in
+ Applications (IDNA)</title>
+ <pubdate>March 2003</pubdate>
+ </biblioentry>
+ </bibliodiv>
+ <bibliodiv>
+ <title>Other <acronym>DNS</acronym>-related RFCs</title>
+ <note>
+ <para>
+ Note: the following list of RFCs, although
+ <acronym>DNS</acronym>-related, are not
+ concerned with implementing software.
+ </para>
+ </note>
+ <biblioentry>
+ <abbrev>RFC1464</abbrev>
+ <author>
+ <surname>Rosenbaum</surname>
+ <firstname>R.</firstname>
+ </author>
+ <title>Using the Domain Name System To Store Arbitrary String
+ Attributes</title>
+ <pubdate>May 1993</pubdate>
+ </biblioentry>
+ <biblioentry>
+ <abbrev>RFC1713</abbrev>
+ <author>
+ <surname>Romao</surname>
+ <firstname>A.</firstname>
+ </author>
+ <title>Tools for <acronym>DNS</acronym> Debugging</title>
+ <pubdate>November 1994</pubdate>
+ </biblioentry>
+ <biblioentry>
+ <abbrev>RFC1794</abbrev>
+ <author>
+ <surname>Brisco</surname>
+ <firstname>T.</firstname>
+ </author>
+ <title><acronym>DNS</acronym> Support for Load
+ Balancing</title>
+ <pubdate>April 1995</pubdate>
+ </biblioentry>
+ <biblioentry>
+ <abbrev>RFC2240</abbrev>
+ <author>
+ <surname>Vaughan</surname>
+ <firstname>O.</firstname>
+ </author>
+ <title>A Legal Basis for Domain Name Allocation</title>
+ <pubdate>November 1997</pubdate>
+ </biblioentry>
+ <biblioentry>
+ <abbrev>RFC2345</abbrev>
+ <authorgroup>
+ <author>
+ <surname>Klensin</surname>
+ <firstname>J.</firstname>
</author>
<author>
- <firstname>S.</firstname>
- <surname>Rose</surname>
+ <firstname>T.</firstname>
+ <surname>Wolf</surname>
+ </author>
+ <author>
+ <firstname>G.</firstname>
+ <surname>Oglesby</surname>
</author>
</authorgroup>
- <title>DNS Security Introduction and Requirements</title>
- <pubdate>March 2005</pubdate>
+ <title>Domain Names and Company Name Retrieval</title>
+ <pubdate>May 1998</pubdate>
</biblioentry>
<biblioentry>
- <abbrev>RFC4034</abbrev>
- <authorgroup>
+ <abbrev>RFC2352</abbrev>
+ <author>
+ <surname>Vaughan</surname>
+ <firstname>O.</firstname>
+ </author>
+ <title>A Convention For Using Legal Names as Domain Names</title>
+ <pubdate>May 1998</pubdate>
+ </biblioentry>
+ <biblioentry>
+ <abbrev>RFC3071</abbrev>
+ <authorgroup>
<author>
- <firstname>R.</firstname>
- <surname>Arends</surname>
+ <surname>Klensin</surname>
+ <firstname>J.</firstname>
+ </author>
+ </authorgroup>
+ <title>Reflections on the DNS, RFC 1591, and Categories of Domains</title>
+ <pubdate>February 2001</pubdate>
+ </biblioentry>
+ <biblioentry>
+ <abbrev>RFC3258</abbrev>
+ <authorgroup>
+ <author>
+ <surname>Hardie</surname>
+ <firstname>T.</firstname>
+ </author>
+ </authorgroup>
+ <title>Distributing Authoritative Name Servers via
+ Shared Unicast Addresses</title>
+ <pubdate>April 2002</pubdate>
+ </biblioentry>
+ <biblioentry>
+ <abbrev>RFC3901</abbrev>
+ <authorgroup>
+ <author>
+ <surname>Durand</surname>
+ <firstname>A.</firstname>
</author>
<author>
- <firstname>R.</firstname>
- <surname>Austein</surname>
+ <firstname>J.</firstname>
+ <surname>Ihren</surname>
+ </author>
+ </authorgroup>
+ <title>DNS IPv6 Transport Operational Guidelines</title>
+ <pubdate>September 2004</pubdate>
+ </biblioentry>
+ </bibliodiv>
+ <bibliodiv>
+ <title>Obsolete and Unimplemented Experimental RFC</title>
+ <biblioentry>
+ <abbrev>RFC1712</abbrev>
+ <authorgroup>
+ <author>
+ <surname>Farrell</surname>
+ <firstname>C.</firstname>
</author>
<author>
<firstname>M.</firstname>
- <surname>Larson</surname>
+ <surname>Schulze</surname>
+ </author>
+ <author>
+ <firstname>S.</firstname>
+ <surname>Pleitner</surname>
</author>
<author>
<firstname>D.</firstname>
- <surname>Massey</surname>
+ <surname>Baldoni</surname>
</author>
+ </authorgroup>
+ <title><acronym>DNS</acronym> Encoding of Geographical
+ Location</title>
+ <pubdate>November 1994</pubdate>
+ </biblioentry>
+ <biblioentry>
+ <abbrev>RFC2673</abbrev>
+ <authorgroup>
<author>
- <firstname>S.</firstname>
- <surname>Rose</surname>
+ <surname>Crawford</surname>
+ <firstname>M.</firstname>
</author>
</authorgroup>
- <title>Resource Records for the DNS Security Extensions</title>
- <pubdate>March 2005</pubdate>
+ <title>Binary Labels in the Domain Name System</title>
+ <pubdate>August 1999</pubdate>
</biblioentry>
<biblioentry>
- <abbrev>RFC4035</abbrev>
- <authorgroup>
+ <abbrev>RFC2874</abbrev>
+ <authorgroup>
<author>
- <firstname>R.</firstname>
- <surname>Arends</surname>
+ <surname>Crawford</surname>
+ <firstname>M.</firstname>
</author>
<author>
- <firstname>R.</firstname>
- <surname>Austein</surname>
+ <surname>Huitema</surname>
+ <firstname>C.</firstname>
+ </author>
+ </authorgroup>
+ <title>DNS Extensions to Support IPv6 Address Aggregation
+ and Renumbering</title>
+ <pubdate>July 2000</pubdate>
+ </biblioentry>
+ </bibliodiv>
+ <bibliodiv>
+ <title>Obsoleted DNS Security RFCs</title>
+ <note>
+ <para>
+ Most of these have been consolidated into RFC4033,
+ RFC4034 and RFC4035 which collectively describe DNSSECbis.
+ </para>
+ </note>
+ <biblioentry>
+ <abbrev>RFC2065</abbrev>
+ <authorgroup>
+ <author>
+ <surname>Eastlake</surname>
+ <lineage>3rd</lineage>
+ <firstname>D.</firstname>
</author>
<author>
- <firstname>M.</firstname>
- <surname>Larson</surname>
+ <firstname>C.</firstname>
+ <surname>Kaufman</surname>
</author>
+ </authorgroup>
+ <title>Domain Name System Security Extensions</title>
+ <pubdate>January 1997</pubdate>
+ </biblioentry>
+ <biblioentry>
+ <abbrev>RFC2137</abbrev>
+ <author>
+ <surname>Eastlake</surname>
+ <lineage>3rd</lineage>
+ <firstname>D.</firstname>
+ </author>
+ <title>Secure Domain Name System Dynamic Update</title>
+ <pubdate>April 1997</pubdate>
+ </biblioentry>
+ <biblioentry>
+ <abbrev>RFC2535</abbrev>
+ <authorgroup>
<author>
+ <surname>Eastlake</surname>
+ <lineage>3rd</lineage>
<firstname>D.</firstname>
- <surname>Massey</surname>
</author>
+ </authorgroup>
+ <title>Domain Name System Security Extensions</title>
+ <pubdate>March 1999</pubdate>
+ </biblioentry>
+ <biblioentry>
+ <abbrev>RFC3008</abbrev>
+ <authorgroup>
<author>
- <firstname>S.</firstname>
- <surname>Rose</surname>
+ <surname>Wellington</surname>
+ <firstname>B.</firstname>
</author>
</authorgroup>
- <title>Protocol Modifications for the DNS
- Security Extensions</title>
- <pubdate>March 2005</pubdate>
+ <title>Domain Name System Security (DNSSEC)
+ Signing Authority</title>
+ <pubdate>November 2000</pubdate>
</biblioentry>
- </bibliodiv>
- <bibliodiv>
- <title>Other Important RFCs About <acronym>DNS</acronym>
- Implementation</title>
- <biblioentry>
- <abbrev>RFC1535</abbrev>
- <author>
- <surname>Gavron</surname>
- <firstname>E.</firstname>
- </author>
- <title>A Security Problem and Proposed Correction With Widely
- Deployed <acronym>DNS</acronym> Software.</title>
- <pubdate>October 1993</pubdate>
- </biblioentry>
- <biblioentry>
- <abbrev>RFC1536</abbrev>
- <authorgroup>
- <author>
- <surname>Kumar</surname>
- <firstname>A.</firstname>
- </author>
- <author>
- <firstname>J.</firstname>
- <surname>Postel</surname>
- </author>
- <author>
- <firstname>C.</firstname>
- <surname>Neuman</surname>
- </author>
- <author>
- <firstname>P.</firstname>
- <surname>Danzig</surname>
- </author>
- <author>
- <firstname>S.</firstname>
- <surname>Miller</surname>
- </author>
- </authorgroup>
- <title>Common <acronym>DNS</acronym> Implementation
- Errors and Suggested Fixes</title>
- <pubdate>October 1993</pubdate>
- </biblioentry>
- <biblioentry>
- <abbrev>RFC1982</abbrev>
- <authorgroup>
- <author>
- <surname>Elz</surname>
- <firstname>R.</firstname>
- </author>
- <author>
- <firstname>R.</firstname>
- <surname>Bush</surname>
- </author>
- </authorgroup>
- <title>Serial Number Arithmetic</title>
- <pubdate>August 1996</pubdate>
- </biblioentry>
- <biblioentry>
- <abbrev>RFC4074</abbrev>
- <authorgroup>
- <author>
- <surname>Morishita</surname>
- <firstname>Y.</firstname>
- </author>
- <author>
- <firstname>T.</firstname>
- <surname>Jinmei</surname>
- </author>
- </authorgroup>
- <title>Common Misbehaviour Against <acronym>DNS</acronym>
- Queries for IPv6 Addresses</title>
- <pubdate>May 2005</pubdate>
- </biblioentry>
- </bibliodiv>
- <bibliodiv>
- <title>Resource Record Types</title>
- <biblioentry>
- <abbrev>RFC1183</abbrev>
- <authorgroup>
- <author>
- <surname>Everhart</surname>
- <firstname>C.F.</firstname>
- </author>
- <author>
- <firstname>L. A.</firstname>
- <surname>Mamakos</surname>
- </author>
- <author>
- <firstname>R.</firstname>
- <surname>Ullmann</surname>
- </author>
- <author>
- <firstname>P.</firstname>
- <surname>Mockapetris</surname>
- </author>
- </authorgroup>
- <title>New <acronym>DNS</acronym> RR Definitions</title>
- <pubdate>October 1990</pubdate>
- </biblioentry>
- <biblioentry>
- <abbrev>RFC1706</abbrev>
- <authorgroup>
- <author>
- <surname>Manning</surname>
- <firstname>B.</firstname>
- </author>
- <author>
- <firstname>R.</firstname>
- <surname>Colella</surname>
- </author>
- </authorgroup>
- <title><acronym>DNS</acronym> NSAP Resource Records</title>
- <pubdate>October 1994</pubdate>
- </biblioentry>
- <biblioentry>
- <abbrev>RFC2168</abbrev>
- <authorgroup>
- <author>
- <surname>Daniel</surname>
- <firstname>R.</firstname>
- </author>
- <author>
- <firstname>M.</firstname>
- <surname>Mealling</surname>
- </author>
- </authorgroup>
- <title>Resolution of Uniform Resource Identifiers using
- the Domain Name System</title>
- <pubdate>June 1997</pubdate>
- </biblioentry>
- <biblioentry>
- <abbrev>RFC1876</abbrev>
- <authorgroup>
- <author>
- <surname>Davis</surname>
- <firstname>C.</firstname>
- </author>
- <author>
- <firstname>P.</firstname>
- <surname>Vixie</surname>
- </author>
- <author>
- <firstname>T.</firstname>
- <firstname>Goodwin</firstname>
- </author>
- <author>
- <firstname>I.</firstname>
- <surname>Dickinson</surname>
- </author>
- </authorgroup>
- <title>A Means for Expressing Location Information in the
- Domain
- Name System</title>
- <pubdate>January 1996</pubdate>
- </biblioentry>
- <biblioentry>
- <abbrev>RFC2052</abbrev>
- <authorgroup>
- <author>
- <surname>Gulbrandsen</surname>
- <firstname>A.</firstname>
- </author>
- <author>
- <firstname>P.</firstname>
- <surname>Vixie</surname>
- </author>
- </authorgroup>
- <title>A <acronym>DNS</acronym> RR for Specifying the
- Location of
- Services.</title>
- <pubdate>October 1996</pubdate>
- </biblioentry>
- <biblioentry>
- <abbrev>RFC2163</abbrev>
- <author>
- <surname>Allocchio</surname>
- <firstname>A.</firstname>
- </author>
- <title>Using the Internet <acronym>DNS</acronym> to
- Distribute MIXER
- Conformant Global Address Mapping</title>
- <pubdate>January 1998</pubdate>
- </biblioentry>
- <biblioentry>
- <abbrev>RFC2230</abbrev>
- <author>
- <surname>Atkinson</surname>
- <firstname>R.</firstname>
- </author>
- <title>Key Exchange Delegation Record for the <acronym>DNS</acronym></title>
- <pubdate>October 1997</pubdate>
- </biblioentry>
- <biblioentry>
- <abbrev>RFC2536</abbrev>
- <author>
- <surname>Eastlake</surname>
- <firstname>D.</firstname>
- <lineage>3rd</lineage>
- </author>
- <title>DSA KEYs and SIGs in the Domain Name System (DNS)</title>
- <pubdate>March 1999</pubdate>
- </biblioentry>
- <biblioentry>
- <abbrev>RFC2537</abbrev>
- <author>
- <surname>Eastlake</surname>
- <firstname>D.</firstname>
- <lineage>3rd</lineage>
- </author>
- <title>RSA/MD5 KEYs and SIGs in the Domain Name System (DNS)</title>
- <pubdate>March 1999</pubdate>
- </biblioentry>
- <biblioentry>
- <abbrev>RFC2538</abbrev>
+ <biblioentry>
+ <abbrev>RFC3090</abbrev>
<authorgroup>
- <author>
- <surname>Eastlake</surname>
- <firstname>D.</firstname>
- <lineage>3rd</lineage>
- </author>
<author>
- <surname>Gudmundsson</surname>
- <firstname>O.</firstname>
+ <surname>Lewis</surname>
+ <firstname>E.</firstname>
</author>
</authorgroup>
- <title>Storing Certificates in the Domain Name System (DNS)</title>
- <pubdate>March 1999</pubdate>
- </biblioentry>
- <biblioentry>
- <abbrev>RFC2539</abbrev>
+ <title>DNS Security Extension Clarification on Zone Status</title>
+ <pubdate>March 2001</pubdate>
+ </biblioentry>
+ <biblioentry>
+ <abbrev>RFC3445</abbrev>
<authorgroup>
- <author>
- <surname>Eastlake</surname>
- <firstname>D.</firstname>
- <lineage>3rd</lineage>
- </author>
+ <author>
+ <surname>Massey</surname>
+ <firstname>D.</firstname>
+ </author>
+ <author>
+ <surname>Rose</surname>
+ <firstname>S.</firstname>
+ </author>
</authorgroup>
- <title>Storage of Diffie-Hellman Keys in the Domain Name System (DNS)</title>
- <pubdate>March 1999</pubdate>
- </biblioentry>
- <biblioentry>
- <abbrev>RFC2540</abbrev>
+ <title>Limiting the Scope of the KEY Resource Record (RR)</title>
+ <pubdate>December 2002</pubdate>
+ </biblioentry>
+ <biblioentry>
+ <abbrev>RFC3655</abbrev>
<authorgroup>
- <author>
- <surname>Eastlake</surname>
- <firstname>D.</firstname>
- <lineage>3rd</lineage>
- </author>
+ <author>
+ <surname>Wellington</surname>
+ <firstname>B.</firstname>
+ </author>
+ <author>
+ <surname>Gudmundsson</surname>
+ <firstname>O.</firstname>
+ </author>
</authorgroup>
- <title>Detached Domain Name System (DNS) Information</title>
- <pubdate>March 1999</pubdate>
- </biblioentry>
- <biblioentry>
- <abbrev>RFC2782</abbrev>
- <author>
- <surname>Gulbrandsen</surname>
- <firstname>A.</firstname>
- </author>
- <author>
- <surname>Vixie</surname>
- <firstname>P.</firstname>
- </author>
- <author>
- <surname>Esibov</surname>
- <firstname>L.</firstname>
- </author>
- <title>A DNS RR for specifying the location of services (DNS SRV)</title>
- <pubdate>February 2000</pubdate>
- </biblioentry>
- <biblioentry>
- <abbrev>RFC2915</abbrev>
- <author>
- <surname>Mealling</surname>
- <firstname>M.</firstname>
- </author>
- <author>
- <surname>Daniel</surname>
- <firstname>R.</firstname>
- </author>
- <title>The Naming Authority Pointer (NAPTR) DNS Resource Record</title>
- <pubdate>September 2000</pubdate>
- </biblioentry>
- <biblioentry>
- <abbrev>RFC3110</abbrev>
- <author>
- <surname>Eastlake</surname>
- <firstname>D.</firstname>
- <lineage>3rd</lineage>
- </author>
- <title>RSA/SHA-1 SIGs and RSA KEYs in the Domain Name System (DNS)</title>
- <pubdate>May 2001</pubdate>
- </biblioentry>
- <biblioentry>
- <abbrev>RFC3123</abbrev>
- <author>
- <surname>Koch</surname>
- <firstname>P.</firstname>
- </author>
- <title>A DNS RR Type for Lists of Address Prefixes (APL RR)</title>
- <pubdate>June 2001</pubdate>
- </biblioentry>
- <biblioentry>
- <abbrev>RFC3596</abbrev>
- <authorgroup>
- <author>
- <surname>Thomson</surname>
- <firstname>S.</firstname>
- </author>
- <author>
- <firstname>C.</firstname>
- <surname>Huitema</surname>
- </author>
- <author>
- <firstname>V.</firstname>
- <surname>Ksinant</surname>
- </author>
- <author>
- <firstname>M.</firstname>
- <surname>Souissi</surname>
- </author>
- </authorgroup>
- <title><acronym>DNS</acronym> Extensions to support IP
- version 6</title>
- <pubdate>October 2003</pubdate>
- </biblioentry>
- <biblioentry>
- <abbrev>RFC3597</abbrev>
- <author>
- <surname>Gustafsson</surname>
- <firstname>A.</firstname>
- </author>
- <title>Handling of Unknown DNS Resource Record (RR) Types</title>
- <pubdate>September 2003</pubdate>
- </biblioentry>
- </bibliodiv>
- <bibliodiv>
- <title><acronym>DNS</acronym> and the Internet</title>
- <biblioentry>
- <abbrev>RFC1101</abbrev>
- <author>
- <surname>Mockapetris</surname>
- <firstname>P. V.</firstname>
- </author>
- <title><acronym>DNS</acronym> Encoding of Network Names
- and Other Types</title>
- <pubdate>April 1989</pubdate>
- </biblioentry>
- <biblioentry>
- <abbrev>RFC1123</abbrev>
- <author>
- <surname>Braden</surname>
- <surname>R.</surname>
- </author>
- <title>Requirements for Internet Hosts - Application and
- Support</title>
- <pubdate>October 1989</pubdate>
- </biblioentry>
- <biblioentry>
- <abbrev>RFC1591</abbrev>
- <author>
- <surname>Postel</surname>
- <firstname>J.</firstname>
- </author>
- <title>Domain Name System Structure and Delegation</title>
- <pubdate>March 1994</pubdate>
- </biblioentry>
- <biblioentry>
- <abbrev>RFC2317</abbrev>
- <authorgroup>
- <author>
- <surname>Eidnes</surname>
- <firstname>H.</firstname>
- </author>
- <author>
- <firstname>G.</firstname>
- <surname>de Groot</surname>
- </author>
- <author>
- <firstname>P.</firstname>
- <surname>Vixie</surname>
- </author>
- </authorgroup>
- <title>Classless IN-ADDR.ARPA Delegation</title>
- <pubdate>March 1998</pubdate>
- </biblioentry>
- <biblioentry>
- <abbrev>RFC2826</abbrev>
- <authorgroup>
- <author>
- <surname>Internet Architecture Board</surname>
- </author>
- </authorgroup>
- <title>IAB Technical Comment on the Unique DNS Root</title>
- <pubdate>May 2000</pubdate>
- </biblioentry>
- <biblioentry>
- <abbrev>RFC2929</abbrev>
- <authorgroup>
- <author>
- <surname>Eastlake</surname>
- <firstname>D.</firstname>
- <lineage>3rd</lineage>
- </author>
- <author>
- <surname>Brunner-Williams</surname>
- <firstname>E.</firstname>
- </author>
- <author>
- <surname>Manning</surname>
- <firstname>B.</firstname>
- </author>
- </authorgroup>
- <title>Domain Name System (DNS) IANA Considerations</title>
- <pubdate>September 2000</pubdate>
- </biblioentry>
- </bibliodiv>
- <bibliodiv>
- <title><acronym>DNS</acronym> Operations</title>
- <biblioentry>
- <abbrev>RFC1033</abbrev>
- <author>
- <surname>Lottor</surname>
- <firstname>M.</firstname>
- </author>
- <title>Domain administrators operations guide.</title>
- <pubdate>November 1987</pubdate>
- </biblioentry>
- <biblioentry>
- <abbrev>RFC1537</abbrev>
- <author>
- <surname>Beertema</surname>
- <firstname>P.</firstname>
- </author>
- <title>Common <acronym>DNS</acronym> Data File
- Configuration Errors</title>
- <pubdate>October 1993</pubdate>
- </biblioentry>
- <biblioentry>
- <abbrev>RFC1912</abbrev>
- <author>
- <surname>Barr</surname>
- <firstname>D.</firstname>
- </author>
- <title>Common <acronym>DNS</acronym> Operational and
- Configuration Errors</title>
- <pubdate>February 1996</pubdate>
- </biblioentry>
- <biblioentry>
- <abbrev>RFC2010</abbrev>
- <authorgroup>
- <author>
- <surname>Manning</surname>
- <firstname>B.</firstname>
- </author>
- <author>
- <firstname>P.</firstname>
- <surname>Vixie</surname>
- </author>
- </authorgroup>
- <title>Operational Criteria for Root Name Servers.</title>
- <pubdate>October 1996</pubdate>
- </biblioentry>
- <biblioentry>
- <abbrev>RFC2219</abbrev>
- <authorgroup>
- <author>
- <surname>Hamilton</surname>
- <firstname>M.</firstname>
- </author>
- <author>
- <firstname>R.</firstname>
- <surname>Wright</surname>
- </author>
- </authorgroup>
- <title>Use of <acronym>DNS</acronym> Aliases for
- Network Services.</title>
- <pubdate>October 1997</pubdate>
- </biblioentry>
- </bibliodiv>
- <bibliodiv>
- <title>Internationalized Domain Names</title>
- <biblioentry>
- <abbrev>RFC2825</abbrev>
+ <title>Redefinition of DNS Authenticated Data (AD) bit</title>
+ <pubdate>November 2003</pubdate>
+ </biblioentry>
+ <biblioentry>
+ <abbrev>RFC3658</abbrev>
<authorgroup>
- <author>
- <surname>IAB</surname>
- </author>
- <author>
- <surname>Daigle</surname>
- <firstname>R.</firstname>
- </author>
+ <author>
+ <surname>Gudmundsson</surname>
+ <firstname>O.</firstname>
+ </author>
</authorgroup>
- <title>A Tangled Web: Issues of I18N, Domain Names,
- and the Other Internet protocols</title>
- <pubdate>May 2000</pubdate>
- </biblioentry>
- <biblioentry>
- <abbrev>RFC3490</abbrev>
+ <title>Delegation Signer (DS) Resource Record (RR)</title>
+ <pubdate>December 2003</pubdate>
+ </biblioentry>
+ <biblioentry>
+ <abbrev>RFC3755</abbrev>
<authorgroup>
- <author>
- <surname>Faltstrom</surname>
- <firstname>P.</firstname>
- </author>
- <author>
- <surname>Hoffman</surname>
- <firstname>P.</firstname>
- </author>
- <author>
- <surname>Costello</surname>
- <firstname>A.</firstname>
- </author>
+ <author>
+ <surname>Weiler</surname>
+ <firstname>S.</firstname>
+ </author>
</authorgroup>
- <title>Internationalizing Domain Names in Applications (IDNA)</title>
- <pubdate>March 2003</pubdate>
- </biblioentry>
- <biblioentry>
- <abbrev>RFC3491</abbrev>
+ <title>Legacy Resolver Compatibility for Delegation Signer (DS)</title>
+ <pubdate>May 2004</pubdate>
+ </biblioentry>
+ <biblioentry>
+ <abbrev>RFC3757</abbrev>
<authorgroup>
- <author>
- <surname>Hoffman</surname>
- <firstname>P.</firstname>
- </author>
- <author>
- <surname>Blanchet</surname>
- <firstname>M.</firstname>
- </author>
+ <author>
+ <surname>Kolkman</surname>
+ <firstname>O.</firstname>
+ </author>
+ <author>
+ <surname>Schlyter</surname>
+ <firstname>J.</firstname>
+ </author>
+ <author>
+ <surname>Lewis</surname>
+ <firstname>E.</firstname>
+ </author>
</authorgroup>
- <title>Nameprep: A Stringprep Profile for Internationalized Domain Names</title>
- <pubdate>March 2003</pubdate>
- </biblioentry>
- <biblioentry>
- <abbrev>RFC3492</abbrev>
+ <title>Domain Name System KEY (DNSKEY) Resource Record
+ (RR) Secure Entry Point (SEP) Flag</title>
+ <pubdate>April 2004</pubdate>
+ </biblioentry>
+ <biblioentry>
+ <abbrev>RFC3845</abbrev>
<authorgroup>
- <surname>Costello</surname>
- <firstname>A.</firstname>
- </author>
+ <author>
+ <surname>Schlyter</surname>
+ <firstname>J.</firstname>
+ </author>
</authorgroup>
- <title>Punycode: A Bootstring encoding of Unicode
- for Internationalized Domain Names in
- Applications (IDNA)</title>
- <pubdate>March 2003</pubdate>
- </biblioentry>
+ <title>DNS Security (DNSSEC) NextSECure (NSEC) RDATA Format</title>
+ <pubdate>August 2004</pubdate>
+ </biblioentry>
</bibliodiv>
- <bibliodiv>
- <title>Other <acronym>DNS</acronym>-related RFCs</title>
- <note>
- <para>
- Note: the following list of RFCs, although
- <acronym>DNS</acronym>-related, are not
- concerned with implementing software.
- </para>
- </note>
- <biblioentry>
- <abbrev>RFC1464</abbrev>
- <author>
- <surname>Rosenbaum</surname>
- <firstname>R.</firstname>
- </author>
- <title>Using the Domain Name System To Store Arbitrary String
- Attributes</title>
- <pubdate>May 1993</pubdate>
- </biblioentry>
- <biblioentry>
- <abbrev>RFC1713</abbrev>
- <author>
- <surname>Romao</surname>
- <firstname>A.</firstname>
- </author>
- <title>Tools for <acronym>DNS</acronym> Debugging</title>
- <pubdate>November 1994</pubdate>
- </biblioentry>
- <biblioentry>
- <abbrev>RFC1794</abbrev>
- <author>
- <surname>Brisco</surname>
- <firstname>T.</firstname>
- </author>
- <title><acronym>DNS</acronym> Support for Load
- Balancing</title>
- <pubdate>April 1995</pubdate>
- </biblioentry>
- <biblioentry>
- <abbrev>RFC2240</abbrev>
- <author>
- <surname>Vaughan</surname>
- <firstname>O.</firstname>
- </author>
- <title>A Legal Basis for Domain Name Allocation</title>
- <pubdate>November 1997</pubdate>
- </biblioentry>
- <biblioentry>
- <abbrev>RFC2345</abbrev>
- <authorgroup>
- <author>
- <surname>Klensin</surname>
- <firstname>J.</firstname>
- </author>
- <author>
- <firstname>T.</firstname>
- <surname>Wolf</surname>
- </author>
- <author>
- <firstname>G.</firstname>
- <surname>Oglesby</surname>
- </author>
- </authorgroup>
- <title>Domain Names and Company Name Retrieval</title>
- <pubdate>May 1998</pubdate>
- </biblioentry>
- <biblioentry>
- <abbrev>RFC2352</abbrev>
- <author>
- <surname>Vaughan</surname>
- <firstname>O.</firstname>
- </author>
- <title>A Convention For Using Legal Names as Domain Names</title>
- <pubdate>May 1998</pubdate>
- </biblioentry>
- <biblioentry>
- <abbrev>RFC3071</abbrev>
- <authorgroup>
- <author>
- <surname>Klensin</surname>
- <firstname>J.</firstname>
- </author>
- </authorgroup>
- <title>Reflections on the DNS, RFC 1591, and Categories of Domains</title>
- <pubdate>February 2001</pubdate>
- </biblioentry>
- <biblioentry>
- <abbrev>RFC3258</abbrev>
- <authorgroup>
- <author>
- <surname>Hardie</surname>
- <firstname>T.</firstname>
- </author>
- </authorgroup>
- <title>Distributing Authoritative Name Servers via
- Shared Unicast Addresses</title>
- <pubdate>April 2002</pubdate>
- </biblioentry>
- <biblioentry>
- <abbrev>RFC3901</abbrev>
- <authorgroup>
- <author>
- <surname>Durand</surname>
- <firstname>A.</firstname>
- </author>
- <author>
- <firstname>J.</firstname>
- <surname>Ihren</surname>
- </author>
- </authorgroup>
- <title>DNS IPv6 Transport Operational Guidelines</title>
- <pubdate>September 2004</pubdate>
- </biblioentry>
- </bibliodiv>
- <bibliodiv>
- <title>Obsolete and Unimplemented Experimental RFC</title>
- <biblioentry>
- <abbrev>RFC1712</abbrev>
- <authorgroup>
- <author>
- <surname>Farrell</surname>
- <firstname>C.</firstname>
- </author>
- <author>
- <firstname>M.</firstname>
- <surname>Schulze</surname>
- </author>
- <author>
- <firstname>S.</firstname>
- <surname>Pleitner</surname>
- </author>
- <author>
- <firstname>D.</firstname>
- <surname>Baldoni</surname>
- </author>
- </authorgroup>
- <title><acronym>DNS</acronym> Encoding of Geographical
- Location</title>
- <pubdate>November 1994</pubdate>
- </biblioentry>
- <biblioentry>
- <abbrev>RFC2673</abbrev>
- <authorgroup>
- <author>
- <surname>Crawford</surname>
- <firstname>M.</firstname>
- </author>
- </authorgroup>
- <title>Binary Labels in the Domain Name System</title>
- <pubdate>August 1999</pubdate>
- </biblioentry>
- <biblioentry>
- <abbrev>RFC2874</abbrev>
- <authorgroup>
- <author>
- <surname>Crawford</surname>
- <firstname>M.</firstname>
- </author>
- <author>
- <surname>Huitema</surname>
- <firstname>C.</firstname>
- </author>
- </authorgroup>
- <title>DNS Extensions to Support IPv6 Address Aggregation
- and Renumbering</title>
- <pubdate>July 2000</pubdate>
- </biblioentry>
- </bibliodiv>
- <bibliodiv>
- <title>Obsoleted DNS Security RFCs</title>
- <note>
- <para>
- Most of these have been consolidated into RFC4033,
- RFC4034 and RFC4035 which collectively describe DNSSECbis.
- </para>
- </note>
- <biblioentry>
- <abbrev>RFC2065</abbrev>
- <authorgroup>
- <author>
- <surname>Eastlake</surname>
- <lineage>3rd</lineage>
- <firstname>D.</firstname>
- </author>
- <author>
- <firstname>C.</firstname>
- <surname>Kaufman</surname>
- </author>
- </authorgroup>
- <title>Domain Name System Security Extensions</title>
- <pubdate>January 1997</pubdate>
- </biblioentry>
- <biblioentry>
- <abbrev>RFC2137</abbrev>
- <author>
- <surname>Eastlake</surname>
- <lineage>3rd</lineage>
- <firstname>D.</firstname>
- </author>
- <title>Secure Domain Name System Dynamic Update</title>
- <pubdate>April 1997</pubdate>
- </biblioentry>
- <biblioentry>
- <abbrev>RFC2535</abbrev>
- <authorgroup>
- <author>
- <surname>Eastlake</surname>
- <lineage>3rd</lineage>
- <firstname>D.</firstname>
- </author>
- </authorgroup>
- <title>Domain Name System Security Extensions</title>
- <pubdate>March 1999</pubdate>
- </biblioentry>
- <biblioentry>
- <abbrev>RFC3008</abbrev>
- <authorgroup>
- <author>
- <surname>Wellington</surname>
- <firstname>B.</firstname>
- </author>
- </authorgroup>
- <title>Domain Name System Security (DNSSEC)
- Signing Authority</title>
- <pubdate>November 2000</pubdate>
- </biblioentry>
- <biblioentry>
- <abbrev>RFC3090</abbrev>
- <authorgroup>
- <author>
- <surname>Lewis</surname>
- <firstname>E.</firstname>
- </author>
- </authorgroup>
- <title>DNS Security Extension Clarification on Zone Status</title>
- <pubdate>March 2001</pubdate>
- </biblioentry>
- <biblioentry>
- <abbrev>RFC3445</abbrev>
- <authorgroup>
- <author>
- <surname>Massey</surname>
- <firstname>D.</firstname>
- </author>
- <author>
- <surname>Rose</surname>
- <firstname>S.</firstname>
- </author>
- </authorgroup>
- <title>Limiting the Scope of the KEY Resource Record (RR)</title>
- <pubdate>December 2002</pubdate>
- </biblioentry>
- <biblioentry>
- <abbrev>RFC3655</abbrev>
- <authorgroup>
- <author>
- <surname>Wellington</surname>
- <firstname>B.</firstname>
- </author>
- <author>
- <surname>Gudmundsson</surname>
- <firstname>O.</firstname>
- </author>
- </authorgroup>
- <title>Redefinition of DNS Authenticated Data (AD) bit</title>
- <pubdate>November 2003</pubdate>
- </biblioentry>
- <biblioentry>
- <abbrev>RFC3658</abbrev>
- <authorgroup>
- <author>
- <surname>Gudmundsson</surname>
- <firstname>O.</firstname>
- </author>
- </authorgroup>
- <title>Delegation Signer (DS) Resource Record (RR)</title>
- <pubdate>December 2003</pubdate>
- </biblioentry>
- <biblioentry>
- <abbrev>RFC3755</abbrev>
- <authorgroup>
- <author>
- <surname>Weiler</surname>
- <firstname>S.</firstname>
- </author>
- </authorgroup>
- <title>Legacy Resolver Compatibility for Delegation Signer (DS)</title>
- <pubdate>May 2004</pubdate>
- </biblioentry>
- <biblioentry>
- <abbrev>RFC3757</abbrev>
- <authorgroup>
- <author>
- <surname>Kolkman</surname>
- <firstname>O.</firstname>
- </author>
- <author>
- <surname>Schlyter</surname>
- <firstname>J.</firstname>
- </author>
- <author>
- <surname>Lewis</surname>
- <firstname>E.</firstname>
- </author>
- </authorgroup>
- <title>Domain Name System KEY (DNSKEY) Resource Record
- (RR) Secure Entry Point (SEP) Flag</title>
- <pubdate>April 2004</pubdate>
- </biblioentry>
- <biblioentry>
- <abbrev>RFC3845</abbrev>
- <authorgroup>
- <author>
- <surname>Schlyter</surname>
- <firstname>J.</firstname>
- </author>
- </authorgroup>
- <title>DNS Security (DNSSEC) NextSECure (NSEC) RDATA Format</title>
- <pubdate>August 2004</pubdate>
- </biblioentry>
- </bibliodiv>
- </bibliography>
- </sect2>
- <sect2 id="internet_drafts">
- <title>Internet Drafts</title>
- <para>
- Internet Drafts (IDs) are rough-draft working documents of
- the Internet Engineering Task Force. They are, in essence, RFCs
- in the preliminary stages of development. Implementors are
- cautioned not
- to regard IDs as archival, and they should not be quoted or cited
- in any formal documents unless accompanied by the disclaimer that
- they are "works in progress." IDs have a lifespan of six months
- after which they are deleted unless updated by their authors.
- </para>
- </sect2>
- <sect2>
- <title>Other Documents About <acronym>BIND</acronym></title>
- <para/>
- <bibliography>
- <biblioentry>
- <authorgroup>
- <author>
- <surname>Albitz</surname>
- <firstname>Paul</firstname>
- </author>
- <author>
- <firstname>Cricket</firstname>
- <surname>Liu</surname>
- </author>
- </authorgroup>
- <title><acronym>DNS</acronym> and <acronym>BIND</acronym></title>
- <copyright>
- <year>1998</year>
- <holder>Sebastopol, CA: O'Reilly and Associates</holder>
- </copyright>
- </biblioentry>
- </bibliography>
- </sect2>
+ </bibliography>
+ </sect2>
+ <sect2 id="internet_drafts">
+ <title>Internet Drafts</title>
+ <para>
+ Internet Drafts (IDs) are rough-draft working documents of
+ the Internet Engineering Task Force. They are, in essence, RFCs
+ in the preliminary stages of development. Implementors are
+ cautioned not
+ to regard IDs as archival, and they should not be quoted or cited
+ in any formal documents unless accompanied by the disclaimer that
+ they are "works in progress." IDs have a lifespan of six months
+ after which they are deleted unless updated by their authors.
+ </para>
+ </sect2>
+ <sect2>
+ <title>Other Documents About <acronym>BIND</acronym></title>
+ <para/>
+ <bibliography>
+ <biblioentry>
+ <authorgroup>
+ <author>
+ <surname>Albitz</surname>
+ <firstname>Paul</firstname>
+ </author>
+ <author>
+ <firstname>Cricket</firstname>
+ <surname>Liu</surname>
+ </author>
+ </authorgroup>
+ <title><acronym>DNS</acronym> and <acronym>BIND</acronym></title>
+ <copyright>
+ <year>1998</year>
+ <holder>Sebastopol, CA: O'Reilly and Associates</holder>
+ </copyright>
+ </biblioentry>
+ </bibliography>
+ </sect2>
</sect1>
<xi:include href="libdns.xml"/>
projects / thirdparty / bind9.git / commitdiff
