man/systemd.snapshot.xml

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   9   Copyright 2010 Lennart Poettering
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  24
  25 <refentry id="systemd.snapshot">
  26         <refentryinfo>
  27                 <title>systemd.snapshot</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>systemd.snapshot</refentrytitle>
  42                 <manvolnum>5</manvolnum>
  43         </refmeta>
  44
  45         <refnamediv>
  46                 <refname>systemd.snapshot</refname>
  47                 <refpurpose>systemd snapshot units</refpurpose>
  48         </refnamediv>
  49
  50         <refsynopsisdiv>
  51                 <para><filename>systemd.snapshot</filename></para>
  52         </refsynopsisdiv>
  53
  54         <refsect1>
  55                 <title>Description</title>
  56
  57                 <para>Snapshot units are not configured via unit
  58                 configuration files. Nonetheless they are named
  59                 similar to filenames. A unit name whose name ends in
  60                 <filename>.snapshot</filename> refers to a dynamic
  61                 snapshot of the systemd runtime state.</para>
  62
  63                 <para>Snapshots are not configured on disk but created
  64                 dynamically via <command>systemctl snapshot</command>
  65                 (see
  66                 <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>8</manvolnum></citerefentry>
  67                 for details) or an equivalent command. When created,
  68                 they will automatically get dependencies on the
  69                 currently activated units. They act as saved
  70                 runtime state of the systemd manager. Later on, the
  71                 user may choose to return to the saved state via
  72                 <command>systemctl isolate</command>. They are
  73                 useful to roll back to a defined state after
  74                 temporarily starting/stopping services or
  75                 similar.</para>
  76         </refsect1>
  77
  78         <refsect1>
  79                   <title>See Also</title>
  80                   <para>
  81                           <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
  82                           <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
  83                           <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>
  84                   </para>
  85         </refsect1>
  86
  87 </refentry>