man/systemd.automount.xml

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   6   SPDX-License-Identifier: LGPL-2.1+
   7
   8   This file is part of systemd.
   9
  10   Copyright 2010 Lennart Poettering
  11 -->
  12
  13 <refentry id="systemd.automount">
  14   <refentryinfo>
  15     <title>systemd.automount</title>
  16     <productname>systemd</productname>
  17
  18     <authorgroup>
  19       <author>
  20         <contrib>Developer</contrib>
  21         <firstname>Lennart</firstname>
  22         <surname>Poettering</surname>
  23         <email>lennart@poettering.net</email>
  24       </author>
  25     </authorgroup>
  26   </refentryinfo>
  27
  28   <refmeta>
  29     <refentrytitle>systemd.automount</refentrytitle>
  30     <manvolnum>5</manvolnum>
  31   </refmeta>
  32
  33   <refnamediv>
  34     <refname>systemd.automount</refname>
  35     <refpurpose>Automount unit configuration</refpurpose>
  36   </refnamediv>
  37
  38   <refsynopsisdiv>
  39     <para><filename><replaceable>automount</replaceable>.automount</filename></para>
  40   </refsynopsisdiv>
  41
  42   <refsect1>
  43     <title>Description</title>
  44
  45     <para>A unit configuration file whose name ends in
  46     <literal>.automount</literal> encodes information about a file
  47     system automount point controlled and supervised by
  48     systemd.</para>
  49
  50     <para>This man page lists the configuration options specific to
  51     this unit type. See
  52     <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>
  53     for the common options of all unit configuration files. The common
  54     configuration items are configured in the generic [Unit] and
  55     [Install] sections. The automount specific configuration options
  56     are configured in the [Automount] section.</para>
  57
  58     <para>Automount units must be named after the automount directories they control. Example: the automount point
  59     <filename noindex='true'>/home/lennart</filename> must be configured in a unit file
  60     <filename>home-lennart.automount</filename>. For details about the escaping logic used to convert a file system
  61     path to a unit name see
  62     <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>. Note that
  63     automount units cannot be templated, nor is it possible to add multiple names to an automount unit by creating
  64     additional symlinks to its unit file.</para>
  65
  66     <para>For each automount unit file a matching mount unit file (see
  67     <citerefentry><refentrytitle>systemd.mount</refentrytitle><manvolnum>5</manvolnum></citerefentry>
  68     for details) must exist which is activated when the automount path
  69     is accessed. Example: if an automount unit
  70     <filename>home-lennart.automount</filename> is active and the user
  71     accesses <filename>/home/lennart</filename> the mount unit
  72     <filename>home-lennart.mount</filename> will be activated.</para>
  73
  74     <para>Automount units may be used to implement on-demand mounting
  75     as well as parallelized mounting of file systems.</para>
  76   </refsect1>
  77
  78   <refsect1>
  79     <title>Automatic Dependencies</title>
  80
  81     <refsect2>
  82       <title>Implicit Dependencies</title>
  83
  84       <para>The following dependencies are implicitly added:</para>
  85
  86       <itemizedlist>
  87         <listitem><para>If an automount unit is beneath another mount unit in the
  88         file system hierarchy, both a requirement and an ordering
  89         dependency between both units are created automatically.</para></listitem>
  90
  91         <listitem><para>An implicit <varname>Before=</varname> dependency is created
  92         between an automount unit and the mount unit it activates.</para></listitem>
  93       </itemizedlist>
  94     </refsect2>
  95
  96     <refsect2>
  97       <title>Default Dependencies</title>
  98
  99       <para>The following dependencies are added unless <varname>DefaultDependencies=no</varname> is set:</para>
 100
 101       <itemizedlist>
 102         <listitem><para>Automount units acquire automatic <varname>Before=</varname> and
 103         <varname>Conflicts=</varname> on <filename>umount.target</filename> in order to be stopped during
 104         shutdown.</para></listitem>
 105       </itemizedlist>
 106     </refsect2>
 107   </refsect1>
 108
 109   <refsect1>
 110     <title><filename>fstab</filename></title>
 111
 112     <para>Automount units may either be configured via unit files, or
 113     via <filename>/etc/fstab</filename> (see
 114     <citerefentry project='man-pages'><refentrytitle>fstab</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 115     for details).</para>
 116
 117     <para>For details how systemd parses
 118     <filename>/etc/fstab</filename> see
 119     <citerefentry><refentrytitle>systemd.mount</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para>
 120
 121     <para>If an automount point is configured in both
 122     <filename>/etc/fstab</filename> and a unit file, the configuration
 123     in the latter takes precedence.</para>
 124   </refsect1>
 125
 126   <refsect1>
 127     <title>Options</title>
 128
 129     <para>Automount files must include an [Automount] section, which
 130     carries information about the file system automount points it
 131     supervises. The options specific to the [Automount] section of
 132     automount units are the following:</para>
 133
 134     <variablelist class='unit-directives'>
 135
 136       <varlistentry>
 137         <term><varname>Where=</varname></term>
 138         <listitem><para>Takes an absolute path of a directory of the
 139         automount point. If the automount point does not exist at time
 140         that the automount point is installed, it is created. This
 141         string must be reflected in the unit filename. (See above.)
 142         This option is mandatory.</para></listitem>
 143       </varlistentry>
 144
 145       <varlistentry>
 146         <term><varname>DirectoryMode=</varname></term>
 147         <listitem><para>Directories of automount points (and any
 148         parent directories) are automatically created if needed. This
 149         option specifies the file system access mode used when
 150         creating these directories. Takes an access mode in octal
 151         notation. Defaults to 0755.</para></listitem>
 152       </varlistentry>
 153       <varlistentry>
 154         <term><varname>TimeoutIdleSec=</varname></term>
 155         <listitem><para>Configures an idle timeout. Once the mount has been
 156         idle for the specified time, systemd will attempt to unmount. Takes a
 157         unit-less value in seconds, or a time span value such as "5min 20s".
 158         Pass 0 to disable the timeout logic. The timeout is disabled by
 159         default.</para></listitem>
 160       </varlistentry>
 161     </variablelist>
 162   </refsect1>
 163
 164   <refsect1>
 165       <title>See Also</title>
 166       <para>
 167         <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 168         <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 169         <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
 170         <citerefentry><refentrytitle>systemd.mount</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
 171         <citerefentry project='man-pages'><refentrytitle>mount</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
 172         <citerefentry project='die-net'><refentrytitle>automount</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
 173         <citerefentry><refentrytitle>systemd.directives</refentrytitle><manvolnum>7</manvolnum></citerefentry>
 174       </para>
 175   </refsect1>
 176
 177 </refentry>