man/nss-mymachines.xml

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  23
  24 <refentry id="nss-mymachines" conditional='ENABLE_MACHINED'>
  25
  26   <refentryinfo>
  27     <title>nss-mymachines</title>
  28     <productname>systemd</productname>
  29
  30     <authorgroup>
  31       <author>
  32         <contrib>Developer</contrib>
  33         <firstname>Lennart</firstname>
  34         <surname>Poettering</surname>
  35         <email>lennart@poettering.net</email>
  36       </author>
  37     </authorgroup>
  38   </refentryinfo>
  39
  40   <refmeta>
  41     <refentrytitle>nss-mymachines</refentrytitle>
  42     <manvolnum>8</manvolnum>
  43   </refmeta>
  44
  45   <refnamediv>
  46     <refname>nss-mymachines</refname>
  47     <refname>libnss_mymachines.so.2</refname>
  48     <refpurpose>Provide hostname resolution for local
  49     container instances.</refpurpose>
  50   </refnamediv>
  51
  52   <refsynopsisdiv>
  53     <para><filename>libnss_mymachines.so.2</filename></para>
  54   </refsynopsisdiv>
  55
  56   <refsect1>
  57     <title>Description</title>
  58
  59     <para><command>nss-mymachines</command> is a plugin for the GNU
  60     Name Service Switch (NSS) functionality of the GNU C Library
  61     (<command>glibc</command>), providing hostname resolution for
  62     container names of containers running locally that are registered
  63     with
  64     <citerefentry><refentrytitle>systemd-machined.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>.
  65     The container names are resolved to the IP addresses of the
  66     specific container, ordered by their scope.</para>
  67
  68     <para>The module also resolves user IDs used by containers to user
  69     names indicating the container name, and back.</para>
  70
  71     <para>To activate the NSS modules, <literal>mymachines</literal>
  72     has to be added to the lines starting with
  73     <literal>hosts:</literal>, <literal>passwd:</literal> and
  74     <literal>group:</literal> in
  75     <filename>/etc/nsswitch.conf</filename>.</para>
  76
  77     <para>It is recommended to place <literal>mymachines</literal>
  78     near the end of the <filename>nsswitch.conf</filename> lines to
  79     make sure that its mappings are only used as fallback, and that any
  80     other mappings, such as DNS or <filename>/etc/hosts</filename>
  81     based mappings, take precedence.</para>
  82   </refsect1>
  83
  84   <refsect1>
  85     <title>Example</title>
  86
  87     <para>Here's an example <filename>/etc/nsswitch.conf</filename>
  88     file that enables <command>mymachines</command> correctly:</para>
  89
  90     <programlisting>passwd:         compat <command>mymachines</command>
  91 group:          compat <command>mymachines</command>
  92 shadow:         compat
  93
  94 hosts:          files resolve <command>mymachines</command> myhostname
  95 networks:       files
  96
  97 protocols:      db files
  98 services:       db files
  99 ethers:         db files
 100 rpc:            db files
 101
 102 netgroup:       nis</programlisting>
 103
 104   </refsect1>
 105
 106   <refsect1>
 107     <title>See Also</title>
 108     <para>
 109       <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 110       <citerefentry><refentrytitle>systemd-machined.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
 111       <citerefentry><refentrytitle>nss-resolve</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
 112       <citerefentry><refentrytitle>nss-myhostname</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
 113       <citerefentry project='man-pages'><refentrytitle>nsswitch.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
 114       <citerefentry project='man-pages'><refentrytitle>getent</refentrytitle><manvolnum>1</manvolnum></citerefentry>
 115     </para>
 116   </refsect1>
 117
 118 </refentry>