--- /dev/null
+<?xml version='1.0'?> <!--*-nxml-*-->
+<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
+ "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
+
+<!--
+ 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
+ (at your option) any later version.
+
+ systemd is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with systemd; If not, see <http://www.gnu.org/licenses/>.
+-->
+
+<refentry id="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>
+ <refentrytitle>nss-myhostname</refentrytitle>
+ <manvolnum>8</manvolnum>
+ </refmeta>
+
+ <refnamediv>
+ <refname>nss-myhostname</refname>
+ <refpurpose>Provide host name resolution for the locally
+ configured system hostname.</refpurpose>
+ </refnamediv>
+
+ <refsynopsisdiv>
+ <cmdsynopsis>
+ <command>nss-myhostname.la</command>
+ </cmdsynopsis>
+ </refsynopsisdiv>
+
+ <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>)
+ providing host name resolution for the locally configured system
+ hostname as returned by
+ <citerefentry><refentrytitle>gethostname</refentrytitle><manvolnum>2</manvolnum></citerefentry>.
+ Various software relies on an always resolvable local host name. When
+ using dynamic hostnames this is usually achieved by patching
+ <filename>/etc/hosts</filename> at the same time as changing the host
+ name. This however is not ideal since it requires a writable
+ <filename>/etc</filename> file system and is fragile because the file
+ might be edited by the administrator at the same time. <command>nss-myhostname</command>
+ simply returns all locally configure public IP addresses, or -- if none
+ are configured -- the IPv4 address 127.0.0.2 (wich is on the local
+ loopback) and the IPv6 address ::1 (which is the local host) for
+ whatever system hostname is configured locally. Patching
+ <filename>/etc/hosts</filename> is thus no longer necessary.</para>
+
+ <para>To activate the NSS modules, <option>myhostname</option>
+ has to be added to the line starting with "<varname>hosts:</varname>" in
+ <filename>/etc/nsswitch.conf</filename></para>
+
+ <para>It is recommended to put <option>myhostname</option>
+ last in the <filename>nsswitch.conf</filename> line to make
+ sure that this mapping is only used as fallback, and any DNS
+ or <filename>/etc/hosts</filename> based mapping takes precedence.</para>
+ </refsect1>
+
+ <refsect1>
+ <title>Example</title>
+
+ <programlisting>
+# /etc/nsswitch.conf
+
+passwd: compat
+group: compat
+shadow: compat
+
+hosts: files dns <varname>myhostname</varname>
+networks: files
+
+protocols: db files
+services: db files
+ethers: db files
+rpc: db files
+
+netgroup: nis
+ </programlisting>
+
+ <para>To test, use <command>glibc</command>'s <command>getent</command> tool:</para>
+
+ <programlisting>
+$ getent ahosts `hostname`
+::1 STREAM omega
+::1 DGRAM
+::1 RAW
+127.0.0.2 STREAM
+127.0.0.2 DGRAM
+127.0.0.2 RAW
+ </programlisting>
+
+ <para>In this case the local host name is <varname>omega</varname>.</para>
+
+ </refsect1>
+
+ <refsect1>
+ <title>See Also</title>
+ <para>
+ <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>systemd-logind.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>logind.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>loginctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>pam.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>pam.d</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>pam</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>pam_loginuid</refentrytitle><manvolnum>8</manvolnum></citerefentry>
+ </para>
+ </refsect1>
+
+</refentry>
~ianmdlvl / elogind.git / blobdiff