man/systemd.automount.xml

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