man/systemd.automount.xml

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