"http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
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- This file is part of systemd.
-
- Copyright 2011 Lennart Poettering
- Copyright 2013 Tom Gundersen
-
- systemd is free software; you can redistribute it and/or modify it
- under the terms of the GNU Lesser General Public License as published by
- the Free Software Foundation; either version 2.1 of the License, or
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-->
-<refentry id="nss-myhostname" conditional='HAVE_MYHOSTNAME'>
+<refentry id="nss-myhostname" conditional='ENABLE_NSS_MYHOSTNAME'>
<refentryinfo>
<title>nss-myhostname</title>
<productname>systemd</productname>
-
- <authorgroup>
- <author>
- <contrib>Developer</contrib>
- <firstname>Lennart</firstname>
- <surname>Poettering</surname>
- <email>lennart@poettering.net</email>
- </author>
- </authorgroup>
</refentryinfo>
<refmeta>
<refsect1>
<title>Description</title>
- <para><command>nss-myhostname</command> is a plugin for the GNU
- Name Service Switch (NSS) functionality of the GNU C Library
- (<command>glibc</command>), primarily providing hostname resolution
- for the locally configured system hostname as returned by
- <citerefentry><refentrytitle>gethostname</refentrytitle><manvolnum>2</manvolnum></citerefentry>.
- The precise hostnames resolved by this module are:</para>
+ <para><command>nss-myhostname</command> is a plug-in module for the GNU Name Service Switch (NSS) functionality of
+ the GNU C Library (<command>glibc</command>), primarily providing hostname resolution for the locally configured
+ system hostname as returned by
+ <citerefentry><refentrytitle>gethostname</refentrytitle><manvolnum>2</manvolnum></citerefentry>. The precise
+ hostnames resolved by this module are:</para>
<itemizedlist>
<listitem><para>The local, configured hostname is resolved to
is on the local loopback) and the IPv6 address ::1 (which is the
local host).</para></listitem>
- <listitem><para>The hostname <literal>localhost</literal> is
- resolved to the IP addresses 127.0.0.1 and
- ::1.</para></listitem>
+ <listitem><para>The hostnames <literal>localhost</literal> and
+ <literal>localhost.localdomain</literal> (as well as any hostname
+ ending in <literal>.localhost</literal> or <literal>.localhost.localdomain</literal>)
+ are resolved to the IP addresses 127.0.0.1 and ::1.</para></listitem>
- <listitem><para>The hostname <literal>gateway</literal> is
+ <listitem><para>The hostname <literal>_gateway</literal> is
resolved to all current default routing gateway addresses,
ordered by their metric. This assigns a stable hostname to the
current gateway, useful for referencing it independently of the
current network configuration state.</para></listitem>
-
</itemizedlist>
<para>Various software relies on an always-resolvable local
changing <filename>/etc/hosts</filename> is unnecessary, and on
many systems, the file becomes entirely optional.</para>
- <para>To activate the NSS modules, <literal>myhostname</literal>
- has to be added to the line starting with
- <literal>hosts:</literal> in
- <filename>/etc/nsswitch.conf</filename>.</para>
+ <para>To activate the NSS modules, add <literal>myhostname</literal> to the line starting with
+ <literal>hosts:</literal> in <filename>/etc/nsswitch.conf</filename>.</para>
- <para>It is recommended to place <literal>myhostname</literal>
- last in the <filename>nsswitch.conf</filename> line to make sure
- that this mapping is only used as fallback, and that any DNS or
- <filename>/etc/hosts</filename> based mapping takes
- precedence.</para>
+ <para>It is recommended to place <literal>myhostname</literal> last in the <filename>nsswitch.conf</filename>'
+ <literal>hosts:</literal> line to make sure that this mapping is only used as fallback, and that any DNS or
+ <filename>/etc/hosts</filename> based mapping takes precedence.</para>
</refsect1>
<refsect1>
<title>Example</title>
- <para>Here is an example <filename>/etc/nsswitch.conf</filename>
- file that enables <command>myhostname</command> correctly:</para>
+ <para>Here is an example <filename>/etc/nsswitch.conf</filename> file that enables
+ <command>nss-myhostname</command> correctly:</para>
-<programlisting>passwd: compat mymachines
-group: compat mymachines
+<programlisting>passwd: compat mymachines systemd
+group: compat mymachines systemd
shadow: compat
-hosts: files resolve mymachines <command>myhostname</command>
+hosts: files mymachines resolve [!UNAVAIL=return] dns <command>myhostname</command>
networks: files
protocols: db files
<title>See Also</title>
<para>
<citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>nss-systemd</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
<citerefentry><refentrytitle>nss-resolve</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
<citerefentry><refentrytitle>nss-mymachines</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
<citerefentry project='man-pages'><refentrytitle>nsswitch.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
projects / thirdparty / systemd.git / blobdiff