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