systemd/man/systemd.mount.html
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<a href="../libudev/index.html">gudev </a><span style="float:right">systemd 219</span><hr><div class="refentry"><a name="systemd.mount"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>systemd.mount — Mount unit configuration</p></div><div class="refsynopsisdiv"><h2>Synopsis</h2><p><code class="filename"><em class="replaceable"><code>mount</code></em>.mount</code></p></div><div class="refsect1"><a name="idm139734078522512"></a><h2 id="Description">Description<a class="headerlink" title="Permalink to this headline" href="#Description"></a></h2><p>A unit configuration file whose name ends in
"<code class="literal">.mount</code>" encodes information about a file system
mount point controlled and supervised by systemd.</p><p>This man page lists the configuration options specific to
this unit type. See
<a href="systemd.unit.html"><span class="citerefentry"><span class="refentrytitle">systemd.unit</span>(5)</span></a>
for the common options of all unit configuration files. The common
configuration items are configured in the generic [Unit] and
[Install] sections. The mount specific configuration options are
configured in the [Mount] section.</p><p>Additional options are listed in
<a href="systemd.exec.html"><span class="citerefentry"><span class="refentrytitle">systemd.exec</span>(5)</span></a>,
which define the execution environment the
<a href="mount.html"><span class="citerefentry"><span class="refentrytitle">mount</span>(8)</span></a>
binary is executed in, and in
<a href="systemd.kill.html"><span class="citerefentry"><span class="refentrytitle">systemd.kill</span>(5)</span></a>,
which define the way the processes are terminated, and in
<a href="systemd.resource-control.html"><span class="citerefentry"><span class="refentrytitle">systemd.resource-control</span>(5)</span></a>,
which configure resource control settings for the processes of the
service. Note that the User= and Group= options are not
particularly useful for mount units specifying a
"<code class="literal">Type=</code>" option or using configuration not
specified in <code class="filename">/etc/fstab</code>;
<a href="mount.html"><span class="citerefentry"><span class="refentrytitle">mount</span>(8)</span></a>
will refuse options that are not listed in
<code class="filename">/etc/fstab</code> if it is not run as UID 0.</p><p>Mount units must be named after the mount point directories
they control. Example: the mount point
<code class="filename">/home/lennart</code> must be
configured in a unit file <code class="filename">home-lennart.mount</code>.
For details about the escaping logic used to convert a file system
path to a unit name, see
<a href="systemd.unit.html"><span class="citerefentry"><span class="refentrytitle">systemd.unit</span>(5)</span></a>.</p><p>Optionally, a mount unit may be accompanied by an automount
unit, to allow on-demand or parallelized mounting. See
<a href="systemd.automount.html"><span class="citerefentry"><span class="refentrytitle">systemd.automount</span>(5)</span></a>.</p><p>If a mount point is beneath another mount point in the file
system hierarchy, a dependency between both units is created
automatically.</p><p>Mount points created at runtime (independently of unit files
or <code class="filename">/etc/fstab</code>) will be monitored by systemd
and appear like any other mount unit in systemd. See
<code class="filename">/proc/self/mountinfo</code> description in
<a href="http://man7.org/linux/man-pages/man5/proc.5.html"><span class="citerefentry"><span class="refentrytitle">proc</span>(5)</span></a>.
</p><p>Some file systems have special semantics as API file systems
for kernel-to-userspace and userspace-to-userpace interfaces. Some
of them may not be changed via mount units, and cannot be
disabled. For a longer discussion see <a class="ulink" href="http://www.freedesktop.org/wiki/Software/systemd/APIFileSystems" target="_top">API
File Systems</a>.</p></div><div class="refsect1"><a name="idm139734082402144"></a><h2 id="fstab"><code class="filename">fstab</code><a class="headerlink" title="Permalink to this headline" href="#fstab"></a></h2><p>Mount units may either be configured via unit files, or via
<code class="filename">/etc/fstab</code> (see
<a href="fstab.html"><span class="citerefentry"><span class="refentrytitle">fstab</span>(5)</span></a>
for details). Mounts listed in <code class="filename">/etc/fstab</code>
will be converted into native units dynamically at boot and when
the configuration of the system manager is reloaded. In general,
configuring mount points through <code class="filename">/etc/fstab</code>
is the preferred approach. See
<a href="systemd-fstab-generator.html"><span class="citerefentry"><span class="refentrytitle">systemd-fstab-generator</span>(8)</span></a>
for details about the conversion.</p><p>When reading <code class="filename">/etc/fstab</code> a few special
mount options are understood by systemd which influence how
dependencies are created for mount points. systemd will create a
dependency of type <code class="option">Wants</code> or
<code class="option">Requires</code> (see option <code class="option">nofail</code>
below), from either <code class="filename">local-fs.target</code> or
<code class="filename">remote-fs.target</code>, depending whether the file
system is local or remote.</p><div class="variablelist"><dl class="variablelist"><dt id="x-systemd.automount"><span class="term"><code class="option">x-systemd.automount</code></span><a class="headerlink" title="Permalink to this term" href="#x-systemd.automount"></a></dt><dd><p>An automount unit will be created for the file
system. See
<a href="systemd.automount.html"><span class="citerefentry"><span class="refentrytitle">systemd.automount</span>(5)</span></a>
for details.</p></dd><dt id="x-systemd.device-timeout="><span class="term"><code class="option">x-systemd.device-timeout=</code></span><a class="headerlink" title="Permalink to this term" href="#x-systemd.device-timeout="></a></dt><dd><p>Configure how long systemd should wait for a
device to show up before giving up on an entry from
<code class="filename">/etc/fstab</code>. Specify a time in seconds or
explicitly append a unit as "<code class="literal">s</code>",
"<code class="literal">min</code>", "<code class="literal">h</code>",
"<code class="literal">ms</code>".</p><p>Note that this option can only be used in
<code class="filename">/etc/fstab</code>, and will be
ignored when part of <code class="varname">Options=</code>
setting in a unit file.</p></dd><dt id="noauto"><span class="term"><code class="option">noauto</code>, </span><span class="term"><code class="option">auto</code></span><a class="headerlink" title="Permalink to this term" href="#noauto"></a></dt><dd><p>With <code class="option">noauto</code>, this mount will
not be added as a dependency for
<code class="filename">local-fs.target</code> or
<code class="filename">remote-fs.target</code>. This means that it will
not be mounted automatically during boot, unless it is pulled
in by some other unit. Option <code class="option">auto</code> has the
opposite meaning and is the default.</p></dd><dt id="nofail"><span class="term"><code class="option">nofail</code></span><a class="headerlink" title="Permalink to this term" href="#nofail"></a></dt><dd><p>With <code class="option">nofail</code> this mount will
be only wanted, not required, by
<code class="filename">local-fs.target</code> or
<code class="filename">remote-fs.target</code>. This means that the
boot will continue even if this mount point is not mounted
successfully.</p></dd><dt id="x-initrd.mount"><span class="term"><code class="option">x-initrd.mount</code></span><a class="headerlink" title="Permalink to this term" href="#x-initrd.mount"></a></dt><dd><p>An additional filesystem to be mounted in the
initramfs. See <code class="filename">initrd-fs.target</code>
description in
<a href="systemd.special.html"><span class="citerefentry"><span class="refentrytitle">systemd.special</span>(7)</span></a>.
</p></dd></dl></div><p>If a mount point is configured in both
<code class="filename">/etc/fstab</code> and a unit file that is stored
below <code class="filename">/usr</code>, the former will take precedence.
If the unit file is stored below <code class="filename">/etc</code>, it
will take precedence. This means: native unit files take
precedence over traditional configuration files, but this is
superseded by the rule that configuration in
<code class="filename">/etc</code> will always take precedence over
configuration in <code class="filename">/usr</code>.</p></div><div class="refsect1"><a name="idm139734082359936"></a><h2 id="Options">Options<a class="headerlink" title="Permalink to this headline" href="#Options"></a></h2><p>Mount files must include a [Mount] section, which carries
information about the file system mount points it supervises. A
number of options that may be used in this section are shared with
other unit types. These options are documented in
<a href="systemd.exec.html"><span class="citerefentry"><span class="refentrytitle">systemd.exec</span>(5)</span></a>
and
<a href="systemd.kill.html"><span class="citerefentry"><span class="refentrytitle">systemd.kill</span>(5)</span></a>.
The options specific to the [Mount] section of mount units are the
following:</p><div class="variablelist"><dl class="variablelist"><dt id="What="><span class="term"><code class="varname">What=</code></span><a class="headerlink" title="Permalink to this term" href="#What="></a></dt><dd><p>Takes an absolute path of a device node, file
or other resource to mount. See
<a href="mount.html"><span class="citerefentry"><span class="refentrytitle">mount</span>(8)</span></a>
for details. If this refers to a device node, a dependency on
the respective device unit is automatically created. (See
<a href="systemd.device.html"><span class="citerefentry"><span class="refentrytitle">systemd.device</span>(5)</span></a>
for more information.) This option is
mandatory.</p></dd><dt id="Where="><span class="term"><code class="varname">Where=</code></span><a class="headerlink" title="Permalink to this term" href="#Where="></a></dt><dd><p>Takes an absolute path of a directory of the
mount point. If the mount point does not exist at the time of
mounting, it is created. This string must be reflected in the
unit filename. (See above.) This option is
mandatory.</p></dd><dt id="Type="><span class="term"><code class="varname">Type=</code></span><a class="headerlink" title="Permalink to this term" href="#Type="></a></dt><dd><p>Takes a string for the file system type. See
<a href="mount.html"><span class="citerefentry"><span class="refentrytitle">mount</span>(8)</span></a>
for details. This setting is optional.</p></dd><dt id="Options="><span class="term"><code class="varname">Options=</code></span><a class="headerlink" title="Permalink to this term" href="#Options="></a></dt><dd><p>Mount options to use when mounting. This takes
a comma-separated list of options. This setting is
optional.</p></dd><dt id="SloppyOptions="><span class="term"><code class="varname">SloppyOptions=</code></span><a class="headerlink" title="Permalink to this term" href="#SloppyOptions="></a></dt><dd><p>Takes a boolean argument. If true, parsing of
the options specified in <code class="varname">Options=</code> is
relaxed, and unknown mount options are tolerated. This
corresponds with
<a href="mount.html"><span class="citerefentry"><span class="refentrytitle">mount</span>(8)</span></a>'s
<em class="parameter"><code>-s</code></em> switch. Defaults to
off.</p></dd><dt id="DirectoryMode="><span class="term"><code class="varname">DirectoryMode=</code></span><a class="headerlink" title="Permalink to this term" href="#DirectoryMode="></a></dt><dd><p>Directories of mount points (and any parent
directories) are automatically created if needed. This option
specifies the file system access mode used when creating these
directories. Takes an access mode in octal notation. Defaults
to 0755.</p></dd><dt id="TimeoutSec="><span class="term"><code class="varname">TimeoutSec=</code></span><a class="headerlink" title="Permalink to this term" href="#TimeoutSec="></a></dt><dd><p>Configures the time to wait for the mount
command to finish. If a command does not exit within the
configured time, the mount will be considered failed and be
shut down again. All commands still running will be terminated
forcibly via <code class="constant">SIGTERM</code>, and after another
delay of this time with <code class="constant">SIGKILL</code>. (See
<code class="option">KillMode=</code> in
<a href="systemd.kill.html"><span class="citerefentry"><span class="refentrytitle">systemd.kill</span>(5)</span></a>.)
Takes a unit-less value in seconds, or a time span value such
as "5min 20s". Pass 0 to disable the timeout logic. The
default value is set from the manager configuration file's
<code class="varname">DefaultTimeoutStart=</code>
variable.</p></dd></dl></div><p>Check
<a href="systemd.exec.html"><span class="citerefentry"><span class="refentrytitle">systemd.exec</span>(5)</span></a>
and
<a href="systemd.kill.html"><span class="citerefentry"><span class="refentrytitle">systemd.kill</span>(5)</span></a>
for more settings.</p></div><div class="refsect1"><a name="idm139734077426000"></a><h2 id="See Also">See Also<a class="headerlink" title="Permalink to this headline" href="#See%20Also"></a></h2><p>
<a href="systemd.html"><span class="citerefentry"><span class="refentrytitle">systemd</span>(1)</span></a>,
<a href="systemctl.html"><span class="citerefentry"><span class="refentrytitle">systemctl</span>(1)</span></a>,
<a href="systemd.unit.html"><span class="citerefentry"><span class="refentrytitle">systemd.unit</span>(5)</span></a>,
<a href="systemd.exec.html"><span class="citerefentry"><span class="refentrytitle">systemd.exec</span>(5)</span></a>,
<a href="systemd.kill.html"><span class="citerefentry"><span class="refentrytitle">systemd.kill</span>(5)</span></a>,
<a href="systemd.resource-control.html"><span class="citerefentry"><span class="refentrytitle">systemd.resource-control</span>(5)</span></a>,
<a href="systemd.service.html"><span class="citerefentry"><span class="refentrytitle">systemd.service</span>(5)</span></a>,
<a href="systemd.device.html"><span class="citerefentry"><span class="refentrytitle">systemd.device</span>(5)</span></a>,
<a href="http://man7.org/linux/man-pages/man5/proc.5.html"><span class="citerefentry"><span class="refentrytitle">proc</span>(5)</span></a>,
<a href="mount.html"><span class="citerefentry"><span class="refentrytitle">mount</span>(8)</span></a>,
<a href="systemd-fstab-generator.html"><span class="citerefentry"><span class="refentrytitle">systemd-fstab-generator</span>(8)</span></a>,
<a href="systemd.directives.html"><span class="citerefentry"><span class="refentrytitle">systemd.directives</span>(7)</span></a>
</p></div></div></body></html>