<author>
Ondrej Filip <it/<feela@network.cz>/,
Pavel Machek <it/<pavel@ucw.cz>/,
-Martin Mares <it/<mj@ucw.cz>/
+Martin Mares <it/<mj@ucw.cz>/,
+Ondrej Zajicek <it/<santiago@crfreenet.org>/
</author>
<abstract>
<p>A <em/Routing Daemon/ is in UNIX terminology a non-interactive program running on
background which does the dynamic part of Internet routing, that is it communicates
with the other routers, calculates routing tables and sends them to the OS kernel
-which does the actual packet forwarding. There already exist other such routing daemons: routed (RIP only), GateD<HTMLURL URL="http://www.gated.org/">
- (non-free), Zebra<HTMLURL URL="http://www.zebra.org"> and MRTD<HTMLURL URL="http://www.zcu.cz/ftp/mirrors/mmrz/mrtd">, but their capabilities are limited and
-they are relatively hard to configure and maintain.
+which does the actual packet forwarding. There already exist other such routing
+daemons: routed (RIP only), GateD (non-free), Zebra<HTMLURL URL="http://www.zebra.org">
+and MRTD<HTMLURL URL="http://sourceforge.net/projects/mrt">, but their capabilities are
+limited and they are relatively hard to configure and maintain.
<p>BIRD is an Internet Routing Daemon designed to avoid all of these shortcomings,
to support all the routing technology used in the today's Internet or planned to be
<item>multiple routing tables
<item>the Border Gateway Protocol (BGPv4)
<item>the Routing Information Protocol (RIPv2)
- <item>the Open Shortest Path First protocol (OSPFv2)
+ <item>the Open Shortest Path First protocol (OSPFv2, OSPFv3)
<item>a virtual protocol for exchange of routes between different routing tables on a single host
<item>a command-line interface allowing on-line control and inspection
of status of the daemon
Public License.
<p>BIRD has been designed to work on all UNIX-like systems. It has been developed and
-tested under Linux 2.0 to 2.4, but porting to other systems (even non-UNIX ones) should
-be relatively easy due to its highly modular architecture.
+tested under Linux 2.0 to 2.6, and then ported to FreeBSD, NetBSD and OpenBSD, porting to other
+systems (even non-UNIX ones) should be relatively easy due to its highly modular architecture.
<sect>Installing BIRD
enable debug messages and run bird in foreground.
<tag>-D <m/filename of debug log/</tag>
- log debugging information to given file instead of stderr
+ log debugging information to given file instead of stderr.
+
+ <tag>-p</tag>
+ just parse the config file and exit. Return value is zero if the config file is valid,
+ nonzero if there are some errors.
<tag>-s <m/name of communication socket/</tag>
use given filename for a socket for communications with the client, default is <it/prefix/<file>/var/run/bird.ctl</file>.
protocol rip {
export all;
import all;
+ interface "*";
}
</code>
<sect>Global options
<p><descrip>
- <tag>log "<m/filename/"|syslog|stderr all|{ <m/list of classes/ }</tag>
+ <tag>log "<m/filename/"|syslog [name <m/name/]|stderr all|{ <m/list of classes/ }</tag>
Set logging of messages having the given class (either <cf/all/ or <cf/{
- error, trace }/ etc.) into selected destination. Classes are:
+ error, trace }/ etc.) into selected destination (a file specified as a filename string,
+ syslog with optional name argument, or the stderr output). Classes are:
<cf/info/, <cf/warning/, <cf/error/ and <cf/fatal/ for messages about local problems,
<cf/debug/ for debugging messages,
<cf/trace/ when you want to know what happens in the network,
logging of connects and disconnects, 2 and higher for logging of
all client commands). Default: 0.
+ <tag>mrtdump "<m/filename/"</tag>
+ Set MRTdump file name. This option must be specified to allow MRTdump feature.
+ Default: no dump file.
+
+ <tag>mrtdump protocols all|off|{ states, messages }</tag>
+ Set global defaults of MRTdump options. See <cf/mrtdump/ in the following section.
+ Default: off.
+
<tag>filter <m/name local variables/{ <m/commands/ }</tag> Define a filter. You can learn more about filters
in the following chapter.
<tag>router id <m/IPv4 address/</tag> Set BIRD's router ID. It's a world-wide unique identification of your router, usually one of router's IPv4 addresses. Default: in IPv4 version, the lowest IP address of a non-loopback interface. In IPv6 version, this option is mandatory.
+ <tag>listen bgp [address <m/address/] [port <m/port/] [v6only]</tag>
+ This option allows to specify address and port where BGP
+ protocol should listen. It is global option as listening
+ socket is common to all BGP instances. Default is to listen on
+ all addresses (0.0.0.0) and port 179. In IPv6 mode, option
+ <cf/v6only/ can be used to specify that BGP socket should
+ listen to IPv6 connections only. This is needed if you want to
+ run both bird and bird6 on the same port.
+
+ <tag>timeformat route|protocol|base|log "<m/format1/" [<m/limit> "<m/format2/"]</tag>
+ This option allows to specify a format of date/time used by
+ BIRD. The first argument specifies for which purpose such
+ format is used. <cf/route/ is a format used in 'show route'
+ command output, <cf/protocol/ is used in 'show protocols'
+ command output, <cf/base/ is used for other commands and
+ <cf/log/ is used in a log file.
+
+ "<m/format1/" is a format string using <i/strftime(3)/
+ notation (see <i/man strftime/ for details). <m/limit> and
+ "<m/format2/" allow to specify the second format string for
+ times in past deeper than <m/limit/ seconds. There are two
+ shorthands: <cf/iso long/ is a ISO 8601 date/time format
+ (YYYY-MM-DD hh:mm:ss) that can be also specified using <cf/"%F
+ %T"/. <cf/iso short/ is a variant of ISO 8601 that uses just
+ the time format (hh:mm:ss) for near times (up to 20 hours in
+ the past) and the date format (YYYY-MM-DD) for far times. This
+ is a shorthand for <cf/"%T" 72000 "%F"/.
+
+ By default, BIRD uses an short, ad-hoc format for <cf/route/
+ and <cf/protocol/ times, and a <cf/iso long/ similar format
+ (DD-MM-YYYY hh:mm:ss) for <cf/base/ and <cf/log/. These
+ defaults are here for a compatibility with older versions
+ and might change in the future.
+
<tag>table <m/name/</tag> Create a new routing table. The default
routing table is created implicitly, other routing tables have
to be added by this command.
<cf/events/ for events internal to the protocol and
<cf/packets/ for packets sent and received by the protocol. Default: off.
+ <tag>mrtdump all|off|{ states, messages }</tag>
+
+ Set protocol MRTdump flags. MRTdump is a standard binary
+ format for logging information from routing protocols and
+ daemons. These flags control what kind of information is
+ logged from the protocol to the MRTdump file (which must be
+ specified by global <cf/mrtdump/ option, see the previous
+ section). Although these flags are similar to flags of
+ <cf/debug/ option, their meaning is different and
+ protocol-specific. For BGP protocol, <cf/states/ logs BGP
+ state changes and <cf/messages/ logs received BGP messages.
+ Other protocols does not support MRTdump yet.
+
+ <tag>router id <m/IPv4 address/</tag> This option can be used
+ to override global router id for a given protocol. Default:
+ uses global router id.
+
<tag>import all | none | filter <m/name/ | filter { <m/filter commands/ } | where <m/filter expression/</tag>
Specify a filter to be used for filtering routes coming from the protocol to the routing table. <cf/all/ is shorthand for <cf/where true/ and <cf/none/ is shorthand for <cf/where false/. Default: <cf/all/.
<tag>export <m/filter/</tag> This is similar to the <cf>import</cf> keyword, except that it
works in the direction from the routing table to the protocol. Default: <cf/none/.
+ <tag>description "<m/text/"</tag> This is an optional
+ description of the protocol. It is displayed as a part of the
+ output of 'show route all' command.
+
<tag>table <m/name/</tag> Connect this protocol to a non-default routing table.
</descrip>
<p>There are several options that give sense only with certain protocols:
<descrip>
- <tag>passwords { password "<m/password/" from <m/time/ to <m/time/ passive <m/time/ id
- <m/num/ [...] }</tag> Specifies passwords to be used with this protocol. <cf>Passive <m/time/</cf> is
- time from which the password is not used for sending, but it is recognized on reception. <cf/id/ is password ID as needed by
- certain protocols. Format of <cf><m/time/</cf> is <tt>dd-mm-yyyy HH:MM:SS</tt>.
-
- <tag>interface "<m/mask/"|<m/prefix/ [ { <m/option/ ; [...] } ]</tag> Specifies which
- interfaces is this protocol active on and allows you to set options on a
- per-interface basis. Mask is specified as in shell-like patterns, thus <cf>interface
- "*" { mode broadcast; };</cf> will start the protocol on all interfaces with <cf>mode
- broadcast;</cf> option. If the first character of mask is <cf/-/, such interfaces are
- excluded. Masks are parsed left-to-right, thus <cf/interface "-eth*", "*";/ means all but
- the ethernets. Default: none.
+ <tag><label id="dsc-iface">interface [-] [ "<m/mask/" ] [ <m/prefix/ ] [, ...] [ { <m/option/ ; [...] } ]</tag>
+
+ Specifies a set of interfaces on which the protocol is activated with
+ given interface-specific options. A set of interfaces specified by one
+ interface option is described using an interface pattern. The
+ interface pattern consists of a sequence of clauses (separated by
+ commas), each clause may contain a mask, a prefix, or both of them. An
+ interface matches the clause if its name matches the mask (if
+ specified) and its address matches the prefix (if specified). Mask is
+ specified as shell-like pattern.
+
+ An interface matches the pattern if it matches any of its
+ clauses. If the clause begins with <cf/-/, matching interfaces are
+ excluded. Patterns are parsed left-to-right, thus
+ <cf/interface "eth0", -"eth*", "*";/ means eth0 and all
+ non-ethernets.
+
+ An interface option can be used more times with different
+ interfaces-specific options, in that case for given interface
+ the first matching interface option is used.
+
+ This option is allowed in Direct, OSPF and RIP protocols,
+ but in OSPF protocol it is used in <cf/area/ subsection.
+
+ Default: none.
+ Examples:
+
+ <cf>interface "*" { type broadcast; };</cf> - start the protocol on all interfaces with
+ <cf>type broadcast</cf> option.
+
+ <cf>interface "eth1", "eth4", "eth5" { type pointopoint; };</cf> - start the protocol
+ on enumerated interfaces with <cf>type pointopoint</cf> option.
+
+ <cf>interface -192.168.1.0/24, 192.168.0.0/16;</cf> - start the protocol on all
+ interfaces that have address from 192.168.0.0/16, but not
+ from 192.168.1.0/24.
+
+ <cf>interface -192.168.1.0/24, 192.168.0.0/16;</cf> - start the protocol on all
+ interfaces that have address from 192.168.0.0/16, but not
+ from 192.168.1.0/24.
+
+ <cf>interface "eth*" 192.168.1.0/24;</cf> - start the protocol on all
+ ethernet interfaces that have address from 192.168.1.0/24.
+
+ <tag><label id="dsc-pass">password "<m/password/" [ { id <m/num/; generate from <m/time/; generate to <m/time/; accept from <m/time/; accept to <m/time/; } ]</tag>
+ Specifies a password that can be used by the protocol. Password option can
+ be used more times to specify more passwords. If more passwords are
+ specified, it is a protocol-dependent decision which one is really
+ used. Specifying passwords does not mean that authentication is
+ enabled, authentication can be enabled by separate, protocol-dependent
+ <cf/authentication/ option.
+
+ This option is allowed in OSPF and RIP protocols. BGP has also
+ <cf/password/ option, but it is slightly different and described
+ separately.
+
+ Default: none.
+</descrip>
+
+<p>Password option can contain section with some (not necessary all) password sub-options:
+
+<descrip>
+ <tag>id <M>num</M></tag>
+ ID of the password, (0-255). If it's not used, BIRD will choose
+ ID based on an order of the password item in the interface. For
+ example, second password item in one interface will have default
+ ID 2. ID is used by some routing protocols to identify which
+ password was used to authenticate protocol packets.
+
+ <tag>generate from "<m/time/"</tag>
+ The start time of the usage of the password for packet signing.
+ The format of <cf><m/time/</cf> is <tt>dd-mm-yyyy HH:MM:SS</tt>.
+
+ <tag>generate to "<m/time/"</tag>
+ The last time of the usage of the password for packet signing.
+
+ <tag>accept from "<m/time/"</tag>
+ The start time of the usage of the password for packet verification.
+
+ <tag>accept to "<m/time/"</tag>
+ The last time of the usage of the password for packet verification.
</descrip>
<chapt>Remote control
<p>You can use the command-line client <file>birdc</file> to talk with
-a running BIRD. Communication is done using a <file/bird.ctl/ UNIX domain
-socket (unless changed with the <tt/-s/ option given to both the server and
-the client). The commands can perform simple actions such as enabling/disabling
-of protocols, telling BIRD to show various information, telling it to
-show routing table filtered by filter, or asking BIRD to
-reconfigure. Press <tt/?/ at any time to get online help. Option
+a running BIRD. Communication is done using a <file/bird.ctl/ UNIX
+domain socket (unless changed with the <tt/-s/ option given to both
+the server and the client). The commands can perform simple actions
+such as enabling/disabling of protocols, telling BIRD to show various
+information, telling it to show routing table filtered by filter, or
+asking BIRD to reconfigure. Press <tt/?/ at any time to get online
+help. Option <tt/-r/ can be used to enable a restricted mode of BIRD
+client, which allows just read-only commands (<cf/show .../). Option
<tt/-v/ can be passed to the client, to make it dump numeric return
-codes along with the messages. You do not necessarily need to use <file/birdc/ to talk to BIRD, your
-own applications could do that, too -- the format of communication between
-BIRD and <file/birdc/ is stable (see the programmer's documentation).
+codes along with the messages. You do not necessarily need to use
+<file/birdc/ to talk to BIRD, your own applications could do that, too
+-- the format of communication between BIRD and <file/birdc/ is stable
+(see the programmer's documentation).
+
+Many commands have the <m/name/ of the protocol instance as an argument.
+This argument can be omitted if there exists only a single instance.
<p>Here is a brief list of supported functions:
<tag>show protocols [all]</tag>
Show list of protocol instances along with tables they are connected to and protocol status, possibly giving verbose information, if <cf/all/ is specified.
- <tag>show ospf [interface|neighbors] [<m/name/] ["<m/interface/"]</tag>
- Show detailed information about OSPF protocol, possibly giving a verbose list of interfaces and neighbors. The <m/name/ of the protocol instance can be omitted if there exists only a single instance.
+ <tag>show ospf interface [<m/name/] ["<m/interface/"]</tag>
+ Show detailed information about OSPF interfaces.
+
+ <tag>show ospf neighbors [<m/name/] ["<m/interface/"]</tag>
+ Show a list of OSPF neighbors and a state of adjacency to them.
+
+ <tag>show ospf state [<m/name/]</tag>
+ Show detailed information about OSPF areas based on a content of link-state database.
+ It shows network topology, aggregated networks and routers from other areas and external routes.
+
+ <tag>show ospf topology [<m/name/]</tag>
+ Show a topology of OSPF areas based on a content of link-state database.
+ It is just a stripped-down version of 'show ospf state'.
<tag>show static [<m/name/]</tag>
- Show detailed information about static routes. The <m/name/ of the protocol instance can be omitted if there exists only a single instance.
-
+ Show detailed information about static routes.
+
<tag>show interfaces [summary]</tag>
Show the list of interfaces. For each interface, print its type, state, MTU and addresses assigned.
<tag>show symbols</tag>
Show the list of symbols defined in the configuration (names of protocols, routing tables etc.).
- <tag>show route [[for] <m/prefix/|<m/IP/] [table <m/sym/] [filter <m/f/|where <m/c/] [(import|proto) <m/p/] [<m/options/]</tag>
+ <tag>show route [[for] <m/prefix/|<m/IP/] [table <m/sym/] [filter <m/f/|where <m/c/] [(export|preexport) <m/p/] [protocol <m/p/] [<m/options/]</tag>
Show contents of a routing table (by default of the main one),
that is routes, their metrics and (in case the <cf/all/ switch is given)
all their attributes.
<p>You can also ask for printing only routes processed and accepted by
a given filter (<cf>filter <m/name/</cf> or <cf>filter { <m/filter/ }
</cf> or matching a given condition (<cf>where <m/condition/</cf>).
- The <cf/import/ and <cf/proto/ switches ask for printing of entries as
- they would be seen by the specified protocol. With <cf/import/, the
+ The <cf/export/ and <cf/preexport/ switches ask for printing of entries
+ that are exported to the specified protocol. With <cf/preexport/, the
export filter of the protocol is skipped.
+ <p>You can also select just routes added by a specific protocol.
+ <cf>protocol <m/p/</cf>.
+
<p>The <cf/stats/ switch requests showing of route statistics (the
number of networks, number of routes before and after filtering). If
you use <cf/count/ instead, only the statistics will be printed.
+ <tag>configure [soft] ["<m/config file/"]</tag>
+ Reload configuration from a given file. BIRD will smoothly
+ switch itself to the new configuration, protocols are
+ reconfigured if possible, restarted otherwise. Changes in
+ filters usually lead to restart of affected protocols. If
+ <cf/soft/ option is used, changes in filters does not cause
+ BIRD to restart affected protocols, therefore already accepted
+ routes (according to old filters) would be still propagated,
+ but new routes would be processed according to the new
+ filters.
+
<tag>enable|disable|restart <m/name/|"<m/pattern/"|all</tag>
Enable, disable or restart a given protocol instance, instances matching the <cf><m/pattern/</cf> or <cf/all/ instances.
- <tag>configure ["<m/config file/"]</tag>
- Reload configuration from a given file.
+ <tag>reload [in|out] <m/name/|"<m/pattern/"|all</tag>
+
+ Reload a given protocol instance, that means re-import routes
+ from the protocol instance and re-export preferred routes to
+ the instance. If <cf/in/ or <cf/out/ options are used, the
+ command is restricted to one direction (re-import or
+ re-export).
+
+ This command is useful if appropriate filters have changed but
+ the protocol instance was not restarted (or reloaded),
+ therefore it still propagates the old set of routes. For example
+ when <cf/configure soft/ command was used to change filters.
+
+ Re-export always succeeds, but re-import is protocol-dependent
+ and might fail (for example, if BGP neighbor does not support
+ route-refresh extension). In that case, re-export is also
+ skipped. Note that for the pipe protocol, both directions are
+ always reloaded together (<cf/in/ or <cf/out/ options are
+ ignored in that case).
<tag/down/
Shut BIRD down.
to +2000000000. Overflows are not checked. You can use <cf/0x1234/ syntax to write hexadecimal values.
<tag/pair/ This is a pair of two short integers. Each component can have values from 0 to
- 65535. Literals of this type is written as <cf/(1234,5678)/.
+ 65535. Literals of this type are written as <cf/(1234,5678)/. The same syntax can also be
+ used to construct a pair from two arbitrary integer expressions (for example <cf/(1+2,a)/).
+
+ <tag/quad/ This is a dotted quad of numbers used to represent
+ router IDs (and others). Each component can have a value
+ from 0 to 255. Literals of this type are written like IPv4
+ addresses.
<tag/string/ This is a string of characters. There are no ways to modify strings in
filters. You can pass them between functions, assign them to variables of type <cf/string/, print
<cf/.ip/ which extracts the IP address from the pair, and <cf/.len/, which separates prefix
length from the pair. So <cf>1.2.0.0/16.pxlen = 16</cf> is true.
- <tag/int|ip|prefix|pair|enum set/
+ <tag/int|pair|quad|ip|prefix|enum set/
Filters recognize four types of sets. Sets are similar to strings: you can pass them around
- but you can't modify them. Literals of type <cf>set int</cf> look like <cf>
+ but you can't modify them. Literals of type <cf>int set</cf> look like <cf>
[ 1, 2, 5..7 ]</cf>. As you can see, both simple values and ranges are permitted in
- sets. Sets of prefixes are special: you can specify which prefix lengths should match them by
- using <cf>[ 1.0.0.0/8+, 2.0.0.0/8-, 3.0.0.0/8{5,6} ]</cf>. <cf>3.0.0.0/8{5,6}</cf> matches
- prefixes <cf/3.X.X.X/ whose prefix length is 5 to 6. <cf><m>address</m>/<m>num</m>+</cf> is a shorthand for <cf><m>address</m>/{0,<m/num/}</cf>,
- <cf><m>address</m>/<m/num/-</cf> is a shorthand for <cf><m>address</m>/{0,<m/num-1/}</cf>. For example,
- <cf>1.2.0.0/16 ˜ [ 1.0.0.0/8{ 15 , 17 } ]</cf> is true, but
- <cf>1.0.0.0/8 ˜ [ 1.0.0.0/8- ]</cf> is false.
+ sets.
+
+ Sets of prefixes are special: their literals does not allow ranges, but allows
+ prefix patterns that are written as <cf><M>ipaddress</M>/<M>pxlen</M>{<M>low</M>,<M>high</M>}</cf>.
+ Prefix <cf><m>ip1</m>/<m>len1</m></cf> matches prefix pattern <cf><m>ip2</m>/<m>len2</m>{<m>l</m>,<m>h</m>}</cf> iff
+ the first <cf>min(len1, len2)</cf> bits of <cf/ip1/ and <cf/ip2/ are identical and <cf>len1 <= ip1 <= len2</cf>.
+ A valid prefix pattern has to satisfy <cf>low <= high</cf>, but <cf/pxlen/ is not constrained by <cf/low/
+ or <cf/high/. Obviously, a prefix matches a prefix set literal iff it matches any prefix pattern in the
+ prefix set literal.
+
+ There are also two shorthands for prefix patterns: <cf><m>address</m>/<m/len/+</cf> is a shorthand for
+ <cf><m>address</m>/<m/len/{<m/len/,<m/maxlen/}</cf> (where <cf><m>maxlen</m></cf> is 32 for IPv4 and 128 for IPv6),
+ that means network prefix <cf><m>address</m>/<m/len/</cf> and all its subnets. <cf><m>address</m>/<m/len/-</cf>
+ is a shorthand for <cf><m>address</m>/<m/len/{0,<m/len/}</cf>, that means network prefix <cf><m>address</m>/<m/len/</cf>
+ and all its supernets (network prefixes that contain it).
+
+ For example, <cf>[ 1.0.0.0/8, 2.0.0.0/8+, 3.0.0.0/8-, 4.0.0.0/8{16,24} ]</cf> matches
+ prefix <cf>1.0.0.0/8</cf>, all subprefixes of <cf>2.0.0.0/8</cf>, all superprefixes of <cf>3.0.0.0/8</cf> and prefixes
+ <cf/4.X.X.X/ whose prefix length is 16 to 24. <cf>[ 0.0.0.0/0{20,24} ]</cf> matches all prefixes (regardless of
+ IP address) whose prefix length is 20 to 24, <cf>[ 1.2.3.4/32- ]</cf> matches any prefix that contains IP address
+ <cf>1.2.3.4</cf>. <cf>1.2.0.0/16 ˜ [ 1.0.0.0/8{15,17} ]</cf> is true,
+ but <cf>1.0.0.0/16 ˜ [ 1.0.0.0/8- ]</cf> is false.
+
+ Cisco-style patterns like <cf>10.0.0.0/8 ge 16 le 24</cf> can be expressed
+ in BIRD as <cf>10.0.0.0/8{16,24}</cf>, <cf>192.168.0.0/16 le 24</cf> as
+ <cf>192.168.0.0/16{16,24}</cf> and <cf>192.168.0.0/16 ge 24</cf> as
+ <cf>192.168.0.0/16{24,32}</cf>.
<tag/enum/
Enumeration types are fixed sets of possibilities. You can't define your own
<tag/bgppath/
BGP path is a list of autonomous system numbers. You can't write literals of this type.
+ There are several special operators on bgppaths:
+
+ <cf><m/P/.first</cf> returns the first ASN (the neighbor ASN) in path <m/P/.
+
+ <cf><m/P/.last</cf> returns the last ASN (the source ASN) in path <m/P/.
+
+ Both <cf/first/ and <cf/last/ return zero if there is no appropriate ASN,
+ for example if the path contains an AS set element as the first (or the last) part.
+
+ <cf><m/P/.len</cf> returns the length of path <m/P/.
+
+ <cf>prepend(<m/P/,<m/A/)</cf> prepends ASN <m/A/ to path <m/P/ and returns the result.
+ Statement <cf><m/P/ = prepend(<m/P/, <m/A/);</cf> can be shortened to
+ <cf><m/P/.prepend(<m/A/);</cf> if <m/P/ is appropriate route attribute
+ (for example <cf/bgp_path/).
<tag/bgpmask/
BGP masks are patterns used for BGP path matching
- (using <cf>path ˜ /2 3 5 ?/</cf> syntax). The masks
+ (using <cf>path ˜ [= 2 3 5 * =]</cf> syntax). The masks
resemble wildcard patterns as used by UNIX shells. Autonomous
- system numbers match themselves, <cf/?/ matches any (even empty)
- sequence of arbitrary AS numbers (<cf/*/ hasn't been chosen, because
- <cf>/*</cf> starts a comment). For example:
- <tt>/4 3 2 1/ ˜ /? 4 3 ?/</tt> is true, but
- <tt>/4 3 2 1/ ˜ /? 4 5 ?/</tt> is false.
- <tag/clist/
- Community list is similar to set of pairs,
- except that unlike other sets, it can be modified.
- There exist no literals of this type.
+ system numbers match themselves, <cf/*/ matches any (even empty)
+ sequence of arbitrary AS numbers and <cf/?/ matches one arbitrary AS number.
+ For example, if <cf>bgp_path</cf> is 4 3 2 1, then:
+ <tt>bgp_path ˜ [= * 4 3 * =]</tt> is true, but
+ <tt>bgp_path ˜ [= * 4 5 * =]</tt> is false.
+ BGP mask expressions can also contain integer expressions enclosed in parenthesis
+ and integer variables, for example <tt>[= * 4 (1+2) a =]</tt>.
+ There is also old syntax that uses / .. / instead of [= .. =] and ? instead of *.
+
+ <tag/clist/
+ Clist is similar to a set, except that unlike other sets, it
+ can be modified. The type is used for community list (a set
+ of pairs) and for cluster list (a set of quads). There exist
+ no literals of this type. There are two special operators on
+ clists:
+
+ <cf>add(<m/C/,<m/P/)</cf> adds pair (or quad) <m/P/ to clist <m/C/ and returns the result.
+
+ <cf>delete(<m/C/,<m/P/)</cf> deletes pair (or quad) <m/P/ from clist <m/C/ and returns the result.
+
+ Statement <cf><m/C/ = add(<m/C/, <m/P/);</cf> can be shortened to
+ <cf><m/C/.add(<m/P/);</cf> if <m/C/ is appropriate route attribute
+ (for example <cf/bgp_community/). Similarly for <cf/delete/.
</descrip>
<p>The filter language supports common integer operators <cf>(+,-,*,/)</cf>, parentheses <cf/(a*(b+c))/, comparison
<cf/(a=b, a!=b, a<b, a>=b)/. Logical operations include unary not (<cf/!/), and (<cf/&&/) and or (<cf/||/).
Special operators include <cf/˜/ for "is element of a set" operation - it can be
-used on element and set of elements of the same type (returning true if element is contained in the given set), or on IP and prefix (returning true if IP is within the range defined by that prefix), or on
-prefix and prefix (returning true if first prefix is more specific than second one) or on bgppath and bgpmask (returning true if the path matches the mask) or on pair and clist (returning true if the community is element of the community list).
+used on element and set of elements of the same type (returning true if element is contained in the given set), or
+on two strings (returning true if first string matches a shell-like pattern stored in second string) or on IP and prefix (returning true if IP is within the range defined by that prefix), or on
+prefix and prefix (returning true if first prefix is more specific than second one) or on bgppath and bgpmask (returning true if the path matches the mask) or on pair and clist (returning true if the pair (or quad) is element of the clist).
<sect>Control structures
attributes just like it accesses variables. Attempts to access undefined
attribute result in a runtime error; you can check if an attribute is
defined by using the <cf>defined( <m>attribute</m> )</cf> operator.
+One notable exception to this rule are attributes of clist type, where
+undefined value is regarded as empty clist for most purposes.
<descrip>
<tag><m/prefix/ net</tag>
Network the route is talking about. Read-only. (See the chapter about routing tables.)
<tag><m/enum/ scope</tag>
- Address scope of the network (<cf/SCOPE_HOST/ for addresses local to this host, <cf/SCOPE_LINK/ for those specific for a physical link, <cf/SCOPE_SITE/ and <cf/SCOPE_ORGANIZATION/ for private addresses, <cf/SCOPE_UNIVERSE/ for globally visible addresses).
+ The scope of the route. Possible values: <cf/SCOPE_HOST/ for
+ routes local to this host, <cf/SCOPE_LINK/ for those specific
+ for a physical link, <cf/SCOPE_SITE/ and
+ <cf/SCOPE_ORGANIZATION/ for private routes and
+ <cf/SCOPE_UNIVERSE/ for globally visible routes. This
+ attribute is not interpreted by BIRD and can be used to mark
+ routes in filters. The default value for new routes is
+ <cf/SCOPE_UNIVERSE/.
<tag><m/int/ preference</tag>
- Preference of the route. (See the chapter about routing tables.)
+ Preference of the route. Valid values are 0-65535. (See the chapter about routing tables.)
<tag><m/ip/ from</tag>
The router which the route has originated from. Read-only.
<tag><m/ip/ gw</tag>
Next hop packets routed using this route should be forwarded to.
+ <tag><m/string/ proto</tag>
+ The name of the protocol which the route has been imported from. Read-only.
+
<tag><m/enum/ source</tag>
- what protocol has told me about this route. Possible values: <cf/RTS_DUMMY/, <cf/RTS_STATIC/, <cf/RTS_INHERIT/, <cf/RTS_DEVICE/, <cf/RTS_STATIC_DEVICE/, <cf/RTS_REDIRECT/, <cf/RTS_RIP/, <cf/RTS_OSPF/, <cf/RTS_OSPF_EXT/, <cf/RTS_OSPF_IA/, <cf/RTS_OSPF_BOUNDARY/, <cf/RTS_BGP/, <cf/RTS_PIPE/.
+ what protocol has told me about this route. Possible values: <cf/RTS_DUMMY/, <cf/RTS_STATIC/, <cf/RTS_INHERIT/, <cf/RTS_DEVICE/, <cf/RTS_STATIC_DEVICE/, <cf/RTS_REDIRECT/, <cf/RTS_RIP/, <cf/RTS_OSPF/, <cf/RTS_OSPF_IA/, <cf/RTS_OSPF_EXT/, <cf/RTS_BGP/, <cf/RTS_PIPE/.
<tag><m/enum/ cast</tag>
- Route type (<cf/RTC_UNICAST/ for normal routes, <cf/RTC_BROADCAST/, <cf/RTC_MULTICAST/, <cf/RTC_ANYCAST/ for broadcast, multicast and anycast routes). Read-only.
+
+ Route type (Currently <cf/RTC_UNICAST/ for normal routes,
+ <cf/RTC_BROADCAST/, <cf/RTC_MULTICAST/, <cf/RTC_ANYCAST/ will
+ be used in the future for broadcast, multicast and anycast
+ routes). Read-only.
<tag><m/enum/ dest</tag>
- Type of destination the packets should be sent to (<cf/RTD_ROUTER/ for forwarding to a neighboring router, <cf/RTD_NETWORK/ for routing to a directly-connected network, <cf/RTD_BLACKHOLE/ for packets to be silently discarded, <cf/RTD_UNREACHABLE/, <cf/RTD_PROHIBIT/ for packets that should be returned with ICMP host unreachable / ICMP administratively prohibited messages). Read-only.
+ Type of destination the packets should be sent to (<cf/RTD_ROUTER/ for forwarding to a neighboring router, <cf/RTD_DEVICE/ for routing to a directly-connected network, <cf/RTD_BLACKHOLE/ for packets to be silently discarded, <cf/RTD_UNREACHABLE/, <cf/RTD_PROHIBIT/ for packets that should be returned with ICMP host unreachable / ICMP administratively prohibited messages). Read-only.
</descrip>
<p>There also exist some protocol-specific attributes which are described in the corresponding protocol sections.
route) in order to avoid routing loops.
<p>BIRD supports all requirements of the BGP4 standard as defined in
-RFC 1771<htmlurl url="ftp://ftp.rfc-editor.org/in-notes/rfc1771.txt">
-including several enhancements from the
-latest draft<htmlurl url="ftp://ftp.rfc-editor.org/internet-drafts/draft-ietf-idr-bgp4-09.txt">.
-It also supports the community attributes as per
-RFC 1997<htmlurl url="ftp://ftp.rfc-editor.org/in-notes/rfc1997.txt">,
-capability negotiation defined in
-RFC 2842<htmlurl url="ftp://ftp.rfc-editor.org/in-notes/rfc2842.txt">.
+RFC 4271<htmlurl url="ftp://ftp.rfc-editor.org/in-notes/rfc4271.txt">
+It also supports the community attributes
+(RFC 1997<htmlurl url="ftp://ftp.rfc-editor.org/in-notes/rfc1997.txt">),
+capability negotiation
+(RFC 3392<htmlurl url="ftp://ftp.rfc-editor.org/in-notes/rfc3392.txt">),
+MD5 password authentication
+(RFC 2385<htmlurl url="ftp://ftp.rfc-editor.org/in-notes/rfc2385.txt">),
+route reflectors
+(RFC 4456<htmlurl url="ftp://ftp.rfc-editor.org/in-notes/rfc4456.txt">),
+multiprotocol extensions
+(RFC 4760<htmlurl url="ftp://ftp.rfc-editor.org/in-notes/rfc4760.txt">),
+and 4B AS numbers
+(RFC 4893<htmlurl url="ftp://ftp.rfc-editor.org/in-notes/rfc4893.txt">).
+
+
For IPv6, it uses the standard multiprotocol extensions defined in
RFC 2283<htmlurl url="ftp://ftp.rfc-editor.org/in-notes/rfc2283.txt">
including changes described in the
we should route via our direct neighbor with address <m/ip/.
Default: switched off.
- <tag>next hop self</tag> Avoid calculation of the Next Hop attribute
- and always advertise our own source address (see below) as a next hop.
- This needs to be used only
- occasionally to circumvent misconfigurations of other routers.
+ <tag>next hop self</tag> Avoid calculation of the Next Hop
+ attribute and always advertise our own source address (see
+ below) as a next hop. This needs to be used only occasionally
+ to circumvent misconfigurations of other routers.
Default: disabled.
+ <tag>missing lladdr self|drop|ignore</tag>Next Hop attribute
+ in BGP-IPv6 sometimes contains just the global IPv6 address,
+ but sometimes it has to contain both global and link-local
+ IPv6 addresses. This option specifies what to do if BIRD have
+ to send both addresses but does not know link-local address.
+ This situation might happen when routes from other protocols
+ are exported to BGP, or when improper updates are received
+ from BGP peers. <cf/self/ means that BIRD advertises its own
+ local address instead. <cf/drop/ means that BIRD skips that
+ prefixes and logs error. <cf/ignore/ means that BIRD ignores
+ the problem and sends just the global address (and therefore
+ forms improper BGP update). Default: <cf/self/, unless BIRD
+ is configured as a route server (option <cf/rs client/), in
+ that case default is <cf/drop/, because route servers usually
+ does not forward packets ifselves.
+
<tag>source address <m/ip/</tag> Define local address we should use
for next hop calculation. Default: the address of the local end
of the interface our neighbor is connected to.
+ <tag>password <m/string/</tag> Use this password for MD5 authentication
+ of BGP sessions. Default: no authentication. Password has to be set by
+ external utility (e.g. setkey(8)) on BSD systems.
+
+ <tag>passive <m/switch/</tag> Standard BGP behavior is both
+ initiating outgoing connections and accepting incoming
+ connections. In passive mode, outgoing connections are not
+ initiated. Default: off.
+
+ <tag>rr client</tag> Be a route reflector and treat the neighbor as
+ a route reflection client. Default: disabled.
+
+ <tag>rr cluster id <m/IPv4 address/</tag> Route reflectors use cluster id
+ to avoid route reflection loops. When there is one route reflector in a cluster
+ it usually uses its router id as a cluster id, but when there are more route
+ reflectors in a cluster, these need to be configured (using this option) to
+ use a common cluster id. Clients in a cluster need not know their cluster
+ id and this option is not allowed for them. Default: the same as router id.
+
+ <tag>rs client</tag> Be a route server and treat the neighbor
+ as a route server client. A route server is used as a
+ replacement for full mesh EBGP routing in Internet exchange
+ points in a similar way to route reflectors used in IBGP routing.
+ BIRD does not implement obsoleted RFC 1863, but uses ad-hoc implementation,
+ which behaves like plain EBGP but reduces modifications to advertised route
+ attributes to be transparent (for example does not prepend its AS number to
+ AS PATH attribute and keep MED attribute). Default: disabled.
+
+ <tag>enable route refresh <m/switch/</tag> When BGP speaker
+ changes its import filter, it has to re-examine all routes
+ received from its neighbor against the new filter. As these
+ routes might not be available, there is a BGP protocol
+ extension Route Refresh (specified in RFC 2918) that allows
+ BGP speaker to request re-advertisement of all routes from its
+ neighbor. This option specifies whether BIRD advertises this
+ capability and accepts such requests. Even when disabled, BIRD
+ can send route refresh requests. Default: on.
+
+ <tag>interpret communities <m/switch/</tag> RFC 1997 demands
+ that BGP speaker should process well-known communities like
+ no-export (65535, 65281) or no-advertise (65535, 65282). For
+ example, received route carrying a no-adverise community
+ should not be advertised to any of its neighbors. If this
+ option is enabled (which is by default), BIRD has such
+ behavior automatically (it is evaluated when a route is
+ exported to the BGP protocol just before the export filter).
+ Otherwise, this integrated processing of well-known
+ communities is disabled. In that case, similar behavior can be
+ implemented in the export filter. Default: on.
+
+ <tag>enable as4 <m/switch/</tag> BGP protocol was designed to use 2B AS numbers
+ and was extended later to allow 4B AS number. BIRD supports 4B AS extension,
+ but by disabling this option it can be persuaded not to advertise it and
+ to maintain old-style sessions with its neighbors. This might be useful for
+ circumventing bugs in neighbor's implementation of 4B AS extension.
+ Even when disabled (off), BIRD behaves internally as AS4-aware BGP router.
+ Default: on.
+
+ <tag>capabilities <m/switch/</tag> Use capability advertisement
+ to advertise optional capabilities. This is standard behavior
+ for newer BGP implementations, but there might be some older
+ BGP implementations that reject such connection attempts.
+ When disabled (off), features that request it (4B AS support)
+ are also disabled. Default: on, with automatic fallback to
+ off when received capability-related error.
+
+ <tag>advertise ipv4 <m/switch/</tag> Advertise IPv4 multiprotocol capability.
+ This is not a correct behavior according to the strict interpretation
+ of RFC 4760, but it is widespread and required by some BGP
+ implementations (Cisco and Quagga). This option is relevant
+ to IPv4 mode with enabled capability advertisement only. Default: on.
+
+ <tag>route limit <m/number/</tag> The maximal number of routes
+ that may be imported from the protocol. If the route limit is
+ exceeded, the connection is closed with error. Default: no limit.
+
<tag>disable after error <m/switch/</tag> When an error is encountered (either
locally or by the other side), disable the instance automatically
and wait for an administrator to fix the problem manually. Default: off.
<tag>path metric <m/switch/</tag> Enable comparison of path lengths
when deciding which BGP route is the best one. Default: on.
+ <tag>prefer older <m/switch/</tag> Standard route selection algorithm
+ breaks ties by comparing router IDs. This changes the behavior
+ to prefer older routes (when both are external and from different
+ peer). For details, see RFC 5004. Default: off.
+
<tag>default bgp_med <m/number/</tag> Value of the Multiple Exit
Discriminator to be used during route selection when the MED attribute
- is missing. Default: infinite.
-
- <tag>default bgp_local_pref <m/number/</tag> Value of the Local Preference
- to be used during route selection when the Local Preference attribute
is missing. Default: 0.
+
+ <tag>default bgp_local_pref <m/number/</tag> A default value
+ for the Local Preference attribute. It is used when a new
+ Local Preference attribute is attached to a route by the BGP
+ protocol itself (for example, if a route is received through
+ eBGP and therefore does not have such attribute). Default: 100
+ (0 in pre-1.2.0 versions of BIRD).
</descrip>
<sect1>Attributes
selection among multiple BGP routes (see the selection rules above). It's
used as an additional metric which is propagated through the whole local AS.
- <tag>int <cf/bgp_med/ [IO]</tag> The Multiple Exit Discriminator of the route
- is an optional attribute which is often used within the local AS to
- reflect interior distances to various boundary routers. See the route selection
- rules above for exact semantics.
+ <tag>int <cf/bgp_med/ [O]</tag> The Multiple Exit Discriminator of the route
+ is an optional attribute which is used on on external (inter-AS) links to
+ convey to an adjacent AS the optimal entry point into the local AS.
+ The received attribute may be also propagated over internal BGP links
+ (and this is default behavior). The attribute value is zeroed when a route
+ is exported from a routing table to a BGP instance to ensure that the attribute
+ received from a neighboring AS is not propagated to other neighboring ASes.
+ A new value might be set in the export filter of a BGP instance.
+ See RFC 4451<htmlurl url="ftp://ftp.rfc-editor.org/in-notes/rfc4451.txt">
+ for further discussion of BGP MED attribute.
<tag>enum <cf/bgp_origin/</tag> Origin of the route: either <cf/ORIGIN_IGP/
if the route has originated in an interior routing protocol or
policy information like "don't export to USA peers". As each AS can define
its own routing policy, it also has a complete freedom about which community
attributes it defines and what will their semantics be.
+
+ <tag>quad <cf/bgp_originator_id/ [O]</tag> This attribute is created by the
+ route reflector when reflecting the route and contains the router ID of the
+ originator of the route in the local AS.
+
+ <tag>clist <cf/bgp_cluster_list/ [O]</tag> This attribute contains a list
+ of cluster IDs of route reflectors. Each route reflector prepends its
+ cluster ID when reflecting the route.
</descrip>
<sect1>Example
bgp_community.add((65000,5678));
# Artificially increase path length
# by advertising local AS number twice
- if bgp_path ~ / 65000 / then
+ if bgp_path ~ [= 65000 =] then
bgp_path.prepend(65000);
accept;
}
this protocol in the configuration since almost all other protocols
require network interfaces to be defined for them to work with.
-<p>The only configurable thing is interface scan time:
+<sect1>Configuration
<p><descrip>
<tag>scan time <m/number/</tag> Time in seconds between two scans
interface status changes asynchronously (such as newer versions of
Linux), we need to scan the list only in order to avoid confusion by lost
notification messages, so the default time is set to a large value.
+
+ <tag>primary [ "<m/mask/" ] <m/prefix/</tag>
+ If a network interface has more than one network address,
+ BIRD has to choose one of them as a primary one, because some
+ routing protocols (for example OSPFv2) suppose there is only
+ one network address per interface. By default, BIRD chooses
+ the lexicographically smallest address as the primary one.
+
+ This option allows to specify which network address should be
+ chosen as a primary one. Network addresses that match
+ <m/prefix/ are preferred to non-matching addresses. If more
+ <cf/primary/ options are used, the first one has the highest
+ preference. If "<m/mask/" is specified, then such
+ <cf/primary/ option is relevant only to matching network
+ interfaces.
+
+ In all cases, an address marked by operating system as
+ secondary cannot be chosen as the primary one.
</descrip>
<p>As the Device protocol doesn't generate any routes, it cannot have
-any attributes. Example configuration looks really simple:
+any attributes. Example configuration looks like this:
<p><code>
protocol device {
scan time 10; # Scan the interfaces often
+ primary "eth0" 192.168.1.1;
+ primary 192.168.0.0/16;
}
</code>
directly connected networks according to the list of interfaces provided
by the kernel via the Device protocol.
-<p>It's highly recommended to include this protocol in your configuration
-unless you want to use BIRD as a route server or a route reflector, that is
-on a machine which doesn't forward packets itself and only participates in
-distribution of routing information.
+<p>The question is whether it is a good idea to have such device
+routes in BIRD routing table. OS kernel usually handles device routes
+for directly connected networks by itself so we don't need (and don't
+want) to export these routes to the kernel protocol. OSPF protocol
+creates device routes for its interfaces itself and BGP protocol is
+usually used for exporting aggregate routes. Although there are some
+use cases that use the direct protocol (like abusing eBGP as an IGP
+routing protocol), in most cases it is not needed to have these device
+routes in BIRD routing table and to use the direct protocol.
<p>The only configurable thing about direct is what interfaces it watches:
<sect>Kernel
<p>The Kernel protocol is not a real routing protocol. Instead of communicating
-the with other routers in the network, it performs synchronization of BIRD's routing
+with other routers in the network, it performs synchronization of BIRD's routing
tables with the OS kernel. Basically, it sends all routing table updates to the kernel
and from time to time it scans the kernel tables to see whether some routes have
disappeared (for example due to unnoticed up/down transition of an interface)
or whether an `alien' route has been added by someone else (depending on the
-<cf/learn/ switch, such routes are either deleted or accepted to our
+<cf/learn/ switch, such routes are either ignored or accepted to our
table).
+<p>Unfortunately, there is one thing that makes the routing table
+synchronization a bit more complicated. In the kernel routing table
+there are also device routes for directly connected networks. These
+routes are usually managed by OS itself (as a part of IP address
+configuration) and we don't want to touch that. They are completely
+ignored during the scan of the kernel tables and also the export of
+device routes from BIRD tables to kernel routing tables is restricted
+to prevent accidental interference. This restriction can be disabled using
+<cf/device routes/ switch.
+
<p>If your OS supports only a single routing table, you can configure only one
instance of the Kernel protocol. If it supports multiple tables (in order to
allow policy routing; such an OS is for example Linux 2.2), you can run as many instances as you want, but each of
routing tables by other routing daemons or by the system administrator.
This is possible only on systems which support identification of route
authorship.
+
+ <tag>device routes <m/switch/</tag> Enable export of device
+ routes to the kernel routing table. By default, such routes
+ are rejected (with the exception of explicitly configured
+ device routes from the static protocol) regardless of the
+ export filter to protect device routes in kernel routing table
+ (managed by OS itself) from accidental overwriting or erasing.
+
<tag>kernel table <m/number/</tag> Select which kernel table should
this particular instance of the Kernel protocol work with. Available
only on systems supporting multiple routing tables.
<sect1>Introduction
<p>Open Shortest Path First (OSPF) is a quite complex interior gateway
-protocol. The current IPv4 version (OSPFv2) is defined in RFC 2328<htmlurl url="ftp://ftp.rfc-editor.org/in-notes/rfc2328.txt">. It's a link
-state (a.k.a. shortest path first) protocol -- each router maintains a database
-describing the autonomous system's topology. Each participating router
-has an identical copy of the database and all routers run the same algorithm
-calculating a shortest path tree with themselves as a root.
-OSPF chooses the least cost path as the best path.
+protocol. The current IPv4 version (OSPFv2) is defined in RFC
+2328<htmlurl url="ftp://ftp.rfc-editor.org/in-notes/rfc2328.txt"> and
+the current IPv6 version (OSPFv3) is defined in RFC 5340<htmlurl
+url="ftp://ftp.rfc-editor.org/in-notes/rfc5340.txt"> It's a link state
+(a.k.a. shortest path first) protocol -- each router maintains a
+database describing the autonomous system's topology. Each participating
+router has an identical copy of the database and all routers run the
+same algorithm calculating a shortest path tree with themselves as a
+root. OSPF chooses the least cost path as the best path.
<p>In OSPF, the autonomous system can be split to several areas in order
to reduce the amount of resources consumed for exchanging the routing
information and to protect the other areas from incorrect routing data.
Topology of the area is hidden to the rest of the autonomous system.
-Unfortunately, multiple OSPF areas are not yet fully supported
-by this version of BIRD and neither is the IPv6 version (OSPFv3).
<p>Another very important feature of OSPF is that
it can keep routing information from other protocols (like Static or BGP)
<code>
protocol ospf <name> {
rfc1583compat <switch>;
+ tick <num>;
area <id> {
stub cost <num>;
- tick <num>;
networks {
<prefix>;
<prefix> hidden;
}
- interface <interface pattern>
- {
+ stubnet <prefix>;
+ stubnet <prefix> {
+ hidden <switch>;
+ summary <switch>;
+ cost <num>;
+ }
+ interface <interface pattern> {
cost <num>;
stub <switch>;
hello <num>;
priority <num>;
wait <num>;
dead count <num>;
+ dead <num>;
+ rx buffer [normal|large|<num>];
type [broadcast|nonbroadcast|pointopoint];
strict nonbroadcast <switch>;
- authentication [none|simple];
+ authentication [none|simple|cryptographic];
password "<text>";
+ password "<text>" {
+ id <num>;
+ generate from "<date>";
+ generate to "<date>";
+ accept from "<date>";
+ accept to "<date>";
+ };
neighbors {
<ip>;
<ip> eligible;
};
};
+ virtual link <id> {
+ hello <num>;
+ retransmit <num>;
+ wait <num>;
+ dead count <num>;
+ dead <num>;
+ authentication [none|simple|cryptographic];
+ password "<text>";
+ };
};
}
</code>
Default value is no. (Area is not stub.)
<tag>tick <M>num</M></tag>
- The routing table calculation is not performed when a single link state
+ The routing table calculation and clean-up of areas' databases
+ is not performed when a single link state
change arrives. To lower the CPU utilization, it's processed later
- at periodical intervals of <m/num/ seconds. The default value is 7.
+ at periodical intervals of <m/num/ seconds. The default value is 1.
<tag>networks { <m/set/ }</tag>
- Definition of area IP ranges. This is used in summary lsa origination.
+ Definition of area IP ranges. This is used in summary LSA origination.
Hidden networks are not propagated into other areas.
+ <tag>stubnet <m/prefix/ { <m/options/ }</tag>
+ Stub networks are networks that are not transit networks
+ between OSPF routers. They are also propagated through an
+ OSPF area as a part of a link state database. By default,
+ BIRD generates a stub network record for each primary network
+ address on each OSPF interface that does not have any OSPF
+ neighbors, and also for each non-primary network address on
+ each OSPF interface. This option allows to alter a set of
+ stub networks propagated by this router.
+
+ Each instance of this option adds a stub network with given
+ network prefix to the set of propagated stub network, unless
+ option <cf/hidden/ is used. It also suppresses default stub
+ networks for given network prefix. When option
+ <cf/summary/ is used, also default stub networks that are
+ subnetworks of given stub network are suppressed. This might
+ be used, for example, to aggregate generated stub networks.
+
<tag>interface <M>pattern</M></tag>
Defines that the specified interfaces belong to the area being defined.
+ See <ref id="dsc-iface" name="interface"> common option for detailed description.
+
+ <tag>virtual link <M>id</M></tag>
+ Virtual link to router with the router id. Virtual link acts as a
+ point-to-point interface belonging to backbone. The actual area is
+ used as transport area. This item cannot be in the backbone.
<tag>cost <M>num</M></tag>
Specifies output cost (metric) of an interface. Default value is 10.
When the router does not receive any messages from a neighbor in
<m/dead count/*<m/hello/ seconds, it will consider the neighbor down.
+ <tag>dead <M>num</M></tag>
+ When the router does not receive any messages from a neighbor in
+ <m/dead/ seconds, it will consider the neighbor down. If both directives
+ <m/dead count/ and <m/dead/ are used, <m/dead/ has precendence.
+
+ <tag>rx buffer <M>num</M></tag>
+ This sets the size of buffer used for receiving packets. The buffer should
+ be bigger than maximal size of any packets. Value NORMAL (default)
+ means 2*MTU, value LARGE means maximal allowed packet - 65536.
+
<tag>type broadcast</tag>
BIRD detects a type of a connected network automatically, but sometimes it's
convenient to force use of a different type manually.
<tag>strict nonbroadcast <M>switch</M></tag>
If set, don't send hello to any undefined neighbor. This switch
- is ignored on on any non-NBMA network. Default is No.
+ is ignored on any non-NBMA network. Default is No.
<tag>authentication none</tag>
No passwords are sent in OSPF packets. This is the default value.
lacking this password are ignored. This authentication mechanism is
very weak.
+ <tag>authentication cryptographic</tag>
+ 16-byte long MD5 digest is appended to every packet. For the digest
+ generation 16-byte long passwords are used. Those passwords are
+ not sent via network, so this mechanism is quite secure.
+ Packets can still be read by an attacker.
+
<tag>password "<M>text</M>"</tag>
- An 8-byte password used for authentication.
+ An 8-byte or 16-byte password used for authentication.
+ See <ref id="dsc-pass" name="password"> common option for detailed description.
<tag>neighbors { <m/set/ } </tag>
A set of neighbors to which Hello messages on nonbroadcast networks
<sect1>Attributes
-<p>OSPF defines three route attributes. Each internal route has a <cf/metric/
+<p>OSPF defines four route attributes. Each internal route has a <cf/metric/.
Metric is ranging from 1 to infinity (65535).
External routes use <cf/metric type 1/ or <cf/metric type 2/.
A <cf/metric of type 1/ is comparable with internal <cf/metric/, a
<cf/metric of type 2/ is always longer
than any <cf/metric of type 1/ or any <cf/internal metric/.
+<cf/Internal metric/ or <cf/metric of type 1/ is stored in attribute
+<cf/ospf_metric1/, <cf/metric type 2/ is stored in attribute <cf/ospf_metric2/.
If you specify both metrics only metric1 is used.
-Each external route can also carry a <cf/tag/ which is a 32-bit
-integer which is used when exporting routes to other protocols;
+
+Each external route can also carry attribute <cf/ospf_tag/ which is a
+32-bit integer which is used when exporting routes to other protocols;
otherwise, it doesn't affect routing inside the OSPF domain at all.
-Default is <cf/metric of type 2 = 10000/ and <cf/tag = 0/.
+The fourth attribute <cf/ospf_router_id/ is a router ID of the router
+advertising that route/network. This attribute is read-only. Default
+is <cf/ospf_metric2 = 10000/ and <cf/ospf_tag = 0/.
<sect1>Example
<code>
protocol ospf MyOSPF {
+ rfc1583compat yes;
+ tick 2;
export filter {
if source = RTS_BGP then {
ospf_metric1 = 100;
accept;
}
- reject;
- };
+ reject;
+ };
area 0.0.0.0 {
- tick 8;
interface "eth*" {
cost 11;
hello 15;
};
interface "ppp*" {
cost 100;
+ authentication cryptographic;
+ password "abc" {
+ id 1;
+ generate to "22-04-2003 11:00:06";
+ accept from "17-01-2001 12:01:05";
+ };
+ password "def" {
+ id 2;
+ generate to "22-07-2005 17:03:21";
+ accept from "22-02-2001 11:34:06";
+ };
};
interface "arc0" {
cost 10;
stub yes;
};
+ interface "arc1";
};
area 120 {
stub yes;
+ networks {
+ 172.16.1.0/24;
+ 172.16.2.0/24 hidden;
+ }
interface "-arc0" , "arc*" {
type nonbroadcast;
authentication none;
of routes from the primary table to the secondary one, import filters control the opposite
direction.
+<p>The Pipe protocol may work in the opaque mode or in the transparent
+mode. In the opaque mode, the Pipe protocol retransmits optimal route
+from one table to the other table in a similar way like other
+protocols send and receive routes. Retransmitted route will have the
+source set to the Pipe protocol, which may limit access to protocol
+specific route attributes. The opaque mode is a default mode.
+
+<p>In transparent mode, the Pipe protocol retransmits all routes from
+one table to the other table, retaining their original source and
+attributes. If import and export filters are set to accept, then both
+tables would have the same content. The mode can be set by
+<tt/mode/ option.
+
<p>The primary use of multiple routing tables and the Pipe protocol is for policy routing,
where handling of a single packet doesn't depend only on its destination address, but also
on its source address, source interface, protocol type and other similar parameters.
-In many systems (Linux 2.2 being a good example), the kernel allows to enforce routing policies
+In many systems (Linux being a good example), the kernel allows to enforce routing policies
by defining routing rules which choose one of several routing tables to be used for a packet
according to its parameters. Setting of these rules is outside the scope of BIRD's work
(on Linux, you can use the <tt/ip/ command), but you can create several routing tables in BIRD,
<sect1>Configuration
<p><descrip>
- <tag>peer table <m/table/</tag> Define secondary routing table to connect to. The
+ <tag>peer table <m/table/</tag> Defines secondary routing table to connect to. The
primary one is selected by the <cf/table/ keyword.
+
+ <tag>mode opaque|transparent</tag> Specifies the mode for the pipe to work in. Default is opaque.
</descrip>
<sect1>Attributes
URL="http://www.ietf.org/html.charters/rip-charter.html" name="http://www.ietf.org/html.charters/rip-charter.html">. Both IPv4
(RFC 1723<htmlurl url="ftp://ftp.rfc-editor.org/in-notes/rfc1723.txt">)
and IPv6 (RFC 2080<htmlurl url="ftp://ftp.rfc-editor.org/in-notes/rfc2080.txt">) versions of RIP are supported by BIRD, historical RIPv1 (RFC 1058<htmlurl url="ftp://ftp.rfc-editor.org/in-notes/rfc1058.txt">)is
-not currently supported. RIPv4 md5 authentication (RFC 2082<htmlurl url="ftp://ftp.rfc-editor.org/in-notes/rfc2082.txt">) is supported.
+not currently supported. RIPv4 MD5 authentication (RFC 2082<htmlurl url="ftp://ftp.rfc-editor.org/in-notes/rfc2082.txt">) is supported.
<p>RIP is a very simple protocol, and it has a lot of shortcomings. Slow
convergence, big network load and inability to handle larger networks
-makes it pretty much obsolete in IPv4 world. (It is still usable on
-very small networks.) It is widely used in IPv6 networks,
-because there are no good implementations of OSPFv3.
+makes it pretty much obsolete. (It is still usable on very small networks.)
<sect1>Configuration
<p>In addition to options common for all to other protocols, RIP supports the following ones:
<descrip>
- <tag/authentication none|password|md5/ selects authentication method to be used. <cf/none/ means that
- packets are not authenticated at all, <cf/password/ means that a plaintext password is embedded
- into each packet, and <cf/md5/ means that packets are authenticated using a md5 cryptographic
- hash. If you set authentication to not-none, it is a good idea to add <cf>passwords { }</cf>
+ <tag/authentication none|plaintext|md5/ selects authentication method to be used. <cf/none/ means that
+ packets are not authenticated at all, <cf/plaintext/ means that a plaintext password is embedded
+ into each packet, and <cf/md5/ means that packets are authenticated using a MD5 cryptographic
+ hash. If you set authentication to not-none, it is a good idea to add <cf>password</cf>
section. Default: none.
<tag>honor always|neighbor|never </tag>specifies when should requests for dumping routing table
port 1520;
period 10;
garbage time 60;
- interface "eth0" { metric 3; mode multicast; }
- "eth1" { metric 2; mode broadcast; };
+ interface "eth0" { metric 3; mode multicast; };
+ interface "eth*" { metric 2; mode broadcast; };
honor neighbor;
authentication none;
import filter { print "importing"; accept; };
implemented in future versions of BIRD:
<itemize>
-<item>OSPF for IPv6 networks
<item>OSPF NSSA areas and opaque LSA's
<item>Route aggregation and flap dampening
<item>Generation of IPv6 router advertisements
projects / thirdparty / bird.git / blobdiff