Systemd/man/nss-mymachines.xml
Yu Watanabe 08540a9591 meson: allow building resolved and machined without nss modules
This adds -Dnss-resolve= and -Dnss-mymachines= meson options.
By using this option, e.g., resolved can be built without nss-resolve.
When no nss modules are built, then test-nss is neither built.

Also, This changes the option name -Dmyhostname= to -Dnss-myhostname=
for consistency to other nss related options.

Closes #9596.
2018-07-23 14:03:05 +02:00

91 lines
3.7 KiB
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<?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">
<!--
SPDX-License-Identifier: LGPL-2.1+
-->
<refentry id="nss-mymachines" conditional='ENABLE_NSS_MYMACHINES'>
<refentryinfo>
<title>nss-mymachines</title>
<productname>systemd</productname>
</refentryinfo>
<refmeta>
<refentrytitle>nss-mymachines</refentrytitle>
<manvolnum>8</manvolnum>
</refmeta>
<refnamediv>
<refname>nss-mymachines</refname>
<refname>libnss_mymachines.so.2</refname>
<refpurpose>Provide hostname resolution for local
container instances.</refpurpose>
</refnamediv>
<refsynopsisdiv>
<para><filename>libnss_mymachines.so.2</filename></para>
</refsynopsisdiv>
<refsect1>
<title>Description</title>
<para><command>nss-mymachines</command> is a plug-in module for the GNU Name Service Switch (NSS) functionality of
the GNU C Library (<command>glibc</command>), providing hostname resolution for the names of containers running
locally that are registered with
<citerefentry><refentrytitle>systemd-machined.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>. The
container names are resolved to the IP addresses of the specific container, ordered by their scope. This
functionality only applies to containers using network namespacing.</para>
<para>The module also resolves user and group IDs used by containers to user and group names indicating the
container name, and back. This functionality only applies to containers using user namespacing.</para>
<para>To activate the NSS module, add <literal>mymachines</literal> to the lines starting with
<literal>hosts:</literal>, <literal>passwd:</literal> and <literal>group:</literal> in
<filename>/etc/nsswitch.conf</filename>.</para>
<para>It is recommended to place <literal>mymachines</literal> after the <literal>files</literal> or
<literal>compat</literal> entry of the <filename>/etc/nsswitch.conf</filename> lines to make sure that its mappings
are preferred over other resolvers such as DNS, but so that <filename>/etc/hosts</filename>,
<filename>/etc/passwd</filename> and <filename>/etc/group</filename> based mappings take precedence.</para>
</refsect1>
<refsect1>
<title>Example</title>
<para>Here is an example <filename>/etc/nsswitch.conf</filename> file that enables
<command>nss-mymachines</command> correctly:</para>
<programlisting>passwd: compat <command>mymachines</command> systemd
group: compat <command>mymachines</command> systemd
shadow: compat
hosts: files <command>mymachines</command> resolve [!UNAVAIL=return] dns myhostname
networks: files
protocols: db files
services: db files
ethers: db files
rpc: db files
netgroup: nis</programlisting>
</refsect1>
<refsect1>
<title>See Also</title>
<para>
<citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
<citerefentry><refentrytitle>systemd-machined.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
<citerefentry><refentrytitle>nss-systemd</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
<citerefentry><refentrytitle>nss-resolve</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
<citerefentry><refentrytitle>nss-myhostname</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
<citerefentry project='man-pages'><refentrytitle>nsswitch.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
<citerefentry project='man-pages'><refentrytitle>getent</refentrytitle><manvolnum>1</manvolnum></citerefentry>
</para>
</refsect1>
</refentry>