man/systemd.automount.xml

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  10   Copyright 2010 Lennart Poettering
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  25
  26 <refentry id="systemd.automount">
  27   <refentryinfo>
  28     <title>systemd.automount</title>
  29     <productname>systemd</productname>
  30
  31     <authorgroup>
  32       <author>
  33         <contrib>Developer</contrib>
  34         <firstname>Lennart</firstname>
  35         <surname>Poettering</surname>
  36         <email>lennart@poettering.net</email>
  37       </author>
  38     </authorgroup>
  39   </refentryinfo>
  40
  41   <refmeta>
  42     <refentrytitle>systemd.automount</refentrytitle>
  43     <manvolnum>5</manvolnum>
  44   </refmeta>
  45
  46   <refnamediv>
  47     <refname>systemd.automount</refname>
  48     <refpurpose>Automount unit configuration</refpurpose>
  49   </refnamediv>
  50
  51   <refsynopsisdiv>
  52     <para><filename><replaceable>automount</replaceable>.automount</filename></para>
  53   </refsynopsisdiv>
  54
  55   <refsect1>
  56     <title>Description</title>
  57
  58     <para>A unit configuration file whose name ends in
  59     <literal>.automount</literal> encodes information about a file
  60     system automount point controlled and supervised by
  61     systemd.</para>
  62
  63     <para>This man page lists the configuration options specific to
  64     this unit type. See
  65     <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>
  66     for the common options of all unit configuration files. The common
  67     configuration items are configured in the generic [Unit] and
  68     [Install] sections. The automount specific configuration options
  69     are configured in the [Automount] section.</para>
  70
  71     <para>Automount units must be named after the automount directories they control. Example: the automount point
  72     <filename noindex='true'>/home/lennart</filename> must be configured in a unit file
  73     <filename>home-lennart.automount</filename>. For details about the escaping logic used to convert a file system
  74     path to a unit name see
  75     <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>. Note that
  76     automount units cannot be templated, nor is it possible to add multiple names to an automount unit by creating
  77     additional symlinks to its unit file.</para>
  78
  79     <para>For each automount unit file a matching mount unit file (see
  80     <citerefentry><refentrytitle>systemd.mount</refentrytitle><manvolnum>5</manvolnum></citerefentry>
  81     for details) must exist which is activated when the automount path
  82     is accessed. Example: if an automount unit
  83     <filename>home-lennart.automount</filename> is active and the user
  84     accesses <filename>/home/lennart</filename> the mount unit
  85     <filename>home-lennart.mount</filename> will be activated.</para>
  86
  87     <para>Automount units may be used to implement on-demand mounting
  88     as well as parallelized mounting of file systems.</para>
  89   </refsect1>
  90
  91   <refsect1>
  92     <title>Implicit Dependencies</title>
  93
  94     <para>The following dependencies are implicitly added:</para>
  95
  96     <itemizedlist>
  97       <listitem><para>If an automount unit is beneath another mount unit in the
  98       file system hierarchy, both a requirement and an ordering
  99       dependency between both units are created automatically.</para></listitem>
 100
 101       <listitem><para>An implicit <varname>Before=</varname> dependency is created
 102       between an automount unit and the mount unit it activates.</para></listitem>
 103     </itemizedlist>
 104   </refsect1>
 105
 106   <refsect1>
 107     <title>Default Dependencies</title>
 108
 109     <para>The following dependencies are added unless <varname>DefaultDependencies=no</varname> is set:</para>
 110
 111     <itemizedlist>
 112       <listitem><para>Automount units acquire automatic <varname>Before=</varname> and
 113       <varname>Conflicts=</varname> on <filename>umount.target</filename> in order to be stopped during
 114       shutdown.</para></listitem>
 115     </itemizedlist>
 116   </refsect1>
 117
 118   <refsect1>
 119     <title><filename>fstab</filename></title>
 120
 121     <para>Automount units may either be configured via unit files, or
 122     via <filename>/etc/fstab</filename> (see
 123     <citerefentry project='man-pages'><refentrytitle>fstab</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 124     for details).</para>
 125
 126     <para>For details how systemd parses
 127     <filename>/etc/fstab</filename> see
 128     <citerefentry><refentrytitle>systemd.mount</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para>
 129
 130     <para>If an automount point is configured in both
 131     <filename>/etc/fstab</filename> and a unit file, the configuration
 132     in the latter takes precedence.</para>
 133   </refsect1>
 134
 135   <refsect1>
 136     <title>Options</title>
 137
 138     <para>Automount files must include an [Automount] section, which
 139     carries information about the file system automount points it
 140     supervises. The options specific to the [Automount] section of
 141     automount units are the following:</para>
 142
 143     <variablelist class='unit-directives'>
 144
 145       <varlistentry>
 146         <term><varname>Where=</varname></term>
 147         <listitem><para>Takes an absolute path of a directory of the
 148         automount point. If the automount point does not exist at time
 149         that the automount point is installed, it is created. This
 150         string must be reflected in the unit filename. (See above.)
 151         This option is mandatory.</para></listitem>
 152       </varlistentry>
 153
 154       <varlistentry>
 155         <term><varname>DirectoryMode=</varname></term>
 156         <listitem><para>Directories of automount points (and any
 157         parent directories) are automatically created if needed. This
 158         option specifies the file system access mode used when
 159         creating these directories. Takes an access mode in octal
 160         notation. Defaults to 0755.</para></listitem>
 161       </varlistentry>
 162       <varlistentry>
 163         <term><varname>TimeoutIdleSec=</varname></term>
 164         <listitem><para>Configures an idle timeout. Once the mount has been
 165         idle for the specified time, systemd will attempt to unmount. Takes a
 166         unit-less value in seconds, or a time span value such as "5min 20s".
 167         Pass 0 to disable the timeout logic. The timeout is disabled by
 168         default.</para></listitem>
 169       </varlistentry>
 170     </variablelist>
 171   </refsect1>
 172
 173   <refsect1>
 174       <title>See Also</title>
 175       <para>
 176         <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 177         <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 178         <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
 179         <citerefentry><refentrytitle>systemd.mount</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
 180         <citerefentry project='man-pages'><refentrytitle>mount</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
 181         <citerefentry project='die-net'><refentrytitle>automount</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
 182         <citerefentry><refentrytitle>systemd.directives</refentrytitle><manvolnum>7</manvolnum></citerefentry>
 183       </para>
 184   </refsect1>
 185
 186 </refentry>