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7 This file is part of systemd.
9 Copyright 2010 Lennart Poettering
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25 <refentry id="systemd.mount">
27 <title>systemd.mount</title>
28 <productname>systemd</productname>
32 <contrib>Developer</contrib>
33 <firstname>Lennart</firstname>
34 <surname>Poettering</surname>
35 <email>lennart@poettering.net</email>
41 <refentrytitle>systemd.mount</refentrytitle>
42 <manvolnum>5</manvolnum>
46 <refname>systemd.mount</refname>
47 <refpurpose>Mount unit configuration</refpurpose>
51 <para><filename><replaceable>mount</replaceable>.mount</filename></para>
55 <title>Description</title>
57 <para>A unit configuration file whose name ends in
58 <literal>.mount</literal> encodes information about
59 a file system mount point controlled and supervised by
62 <para>This man page lists the configuration options
63 specific to this unit type. See
64 <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>
65 for the common options of all unit configuration
66 files. The common configuration items are configured
67 in the generic [Unit] and [Install] sections. The
68 mount specific configuration options are configured
69 in the [Mount] section.</para>
71 <para>Additional options are listed in
72 <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
73 which define the execution environment the
74 <citerefentry><refentrytitle>mount</refentrytitle><manvolnum>8</manvolnum></citerefentry>
75 binary is executed in, and in
76 <citerefentry><refentrytitle>systemd.kill</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
77 which define the way the processes are terminated, and
79 <citerefentry><refentrytitle>systemd.resource-control</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
80 which configure resource control settings for the
81 processes of the service. Note that the User= and
82 Group= options are not particularly useful for mount
83 units specifying a <literal>Type=</literal> option or
84 using configuration not specified in
85 <filename>/etc/fstab</filename>;
86 <citerefentry><refentrytitle>mount</refentrytitle><manvolnum>8</manvolnum></citerefentry>
87 will refuse options that are not listed in
88 <filename>/etc/fstab</filename> if it is not run as
91 <para>Mount units must be named after the mount point
92 directories they control. Example: the mount point
93 <filename noindex='true'>/home/lennart</filename> must be configured
95 <filename>home-lennart.mount</filename>. For details
96 about the escaping logic used to convert a file system
97 path to a unit name, see
98 <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para>
100 <para>Optionally, a mount unit may be accompanied by
101 an automount unit, to allow on-demand or parallelized
103 <citerefentry><refentrytitle>systemd.automount</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para>
105 <para>If a mount point is beneath another mount point
106 in the file system hierarchy, a dependency between both
107 units is created automatically.</para>
109 <para>Mount points created at runtime (independently of
110 unit files or <filename>/etc/fstab</filename>) will be
111 monitored by systemd and appear like any other mount
113 See <filename>/proc/self/mountinfo</filename> description
114 in <citerefentry project='man-pages'><refentrytitle>proc</refentrytitle><manvolnum>5</manvolnum></citerefentry>.
117 <para>Some file systems have special semantics as API
118 file systems for kernel-to-userspace and
119 userspace-to-userpace interfaces. Some of them may not
120 be changed via mount units, and cannot be disabled.
121 For a longer discussion see <ulink
122 url="http://www.freedesktop.org/wiki/Software/systemd/APIFileSystems">API
123 File Systems</ulink>.</para>
127 <title><filename>fstab</filename></title>
129 <para>Mount units may either be configured via unit
130 files, or via <filename>/etc/fstab</filename> (see
131 <citerefentry><refentrytitle>fstab</refentrytitle><manvolnum>5</manvolnum></citerefentry>
132 for details). Mounts listed in
133 <filename>/etc/fstab</filename> will be converted into
134 native units dynamically at boot and when the
135 configuration of the system manager is reloaded. In
136 general, configuring mount points through
137 <filename>/etc/fstab</filename> is the preferred
139 <citerefentry><refentrytitle>systemd-fstab-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>
140 for details about the conversion.</para>
142 <para>When reading <filename>/etc/fstab</filename> a
143 few special mount options are understood by systemd
144 which influence how dependencies are created for mount
145 points. systemd will create a dependency of type
146 <option>Wants</option> or <option>Requires</option>
147 (see option <option>nofail</option> below), from
148 either <filename>local-fs.target</filename> or
149 <filename>remote-fs.target</filename>, depending
150 whether the file system is local or remote.</para>
152 <variablelist class='fstab-options'>
155 <term><option>x-systemd.automount</option></term>
157 <listitem><para>An automount unit will be created
158 for the file system. See
159 <citerefentry><refentrytitle>systemd.automount</refentrytitle><manvolnum>5</manvolnum></citerefentry>
160 for details.</para></listitem>
164 <term><option>x-systemd.device-timeout=</option></term>
166 <listitem><para>Configure how long systemd should
167 wait for a device to show up before giving up on
169 <filename>/etc/fstab</filename>. Specify a time in
170 seconds or explicitly append a unit as
171 <literal>s</literal>, <literal>min</literal>,
172 <literal>h</literal>,
173 <literal>ms</literal>.</para>
175 <para>Note that this option can only be used in
176 <filename>/etc/fstab</filename>, and will be
177 ignored when part of <varname>Options=</varname>
178 setting in a unit file.</para>
183 <term><option>noauto</option></term>
184 <term><option>auto</option></term>
186 <listitem><para>With <option>noauto</option>, this
187 mount will not be added as a dependency for
188 <filename>local-fs.target</filename> or
189 <filename>remote-fs.target</filename>. This means
190 that it will not be mounted automatically during
191 boot, unless it is pulled in by some other
192 unit. Option <option>auto</option> has the
193 opposite meaning and is the default.</para>
198 <term><option>nofail</option></term>
200 <listitem><para>With <option>nofail</option> this
201 mount will be only wanted, not required, by
202 <filename>local-fs.target</filename> or
203 <filename>remote-fs.target</filename>. This means
204 that the boot will continue even if this mount
205 point is not mounted successfully.</para>
210 <term><option>x-initrd.mount</option></term>
212 <listitem><para>An additional filesystem to be
213 mounted in the initramfs. See
214 <filename>initrd-fs.target</filename> description
216 <citerefentry><refentrytitle>systemd.special</refentrytitle><manvolnum>7</manvolnum></citerefentry>.
221 <para>If a mount point is configured in both
222 <filename>/etc/fstab</filename> and a unit file that
223 is stored below <filename>/usr</filename>, the former
224 will take precedence. If the unit file is stored below
225 <filename>/etc</filename>, it will take
226 precedence. This means: native unit files take
227 precedence over traditional configuration files, but
228 this is superseded by the rule that configuration in
229 <filename>/etc</filename> will always take precedence
230 over configuration in
231 <filename>/usr</filename>.</para>
235 <title>Options</title>
237 <para>Mount files must include a [Mount] section,
238 which carries information about the file system mount points it
239 supervises. A number of options that may be used in
240 this section are shared with other unit types. These
241 options are documented in
242 <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>
244 <citerefentry><refentrytitle>systemd.kill</refentrytitle><manvolnum>5</manvolnum></citerefentry>. The
245 options specific to the [Mount] section of mount
246 units are the following:</para>
248 <variablelist class='unit-directives'>
251 <term><varname>What=</varname></term>
252 <listitem><para>Takes an absolute path
253 of a device node, file or other
254 resource to mount. See
255 <citerefentry><refentrytitle>mount</refentrytitle><manvolnum>8</manvolnum></citerefentry>
256 for details. If this refers to a
257 device node, a dependency on the
258 respective device unit is
259 automatically created. (See
260 <citerefentry><refentrytitle>systemd.device</refentrytitle><manvolnum>5</manvolnum></citerefentry> for more information.)
262 mandatory.</para></listitem>
266 <term><varname>Where=</varname></term>
267 <listitem><para>Takes an absolute path
268 of a directory of the mount point. If
269 the mount point does not exist at the
270 time of mounting, it is created. This
271 string must be reflected in the unit
272 filename. (See above.) This option is
273 mandatory.</para></listitem>
277 <term><varname>Type=</varname></term>
278 <listitem><para>Takes a string for the
279 file system type. See
280 <citerefentry><refentrytitle>mount</refentrytitle><manvolnum>8</manvolnum></citerefentry>
281 for details. This setting is
282 optional.</para></listitem>
286 <term><varname>Options=</varname></term>
288 <listitem><para>Mount options to use
289 when mounting. This takes a
290 comma-separated list of options. This
291 setting is optional.</para></listitem>
295 <term><varname>SloppyOptions=</varname></term>
297 <listitem><para>Takes a boolean
298 argument. If true, parsing of the
300 <varname>Options=</varname> is
301 relaxed, and unknown mount options are
302 tolerated. This corresponds with
303 <citerefentry><refentrytitle>mount</refentrytitle><manvolnum>8</manvolnum></citerefentry>'s
304 <parameter>-s</parameter>
306 off.</para></listitem>
310 <term><varname>DirectoryMode=</varname></term>
311 <listitem><para>Directories of mount
312 points (and any parent directories)
313 are automatically created if
314 needed. This option specifies the file
315 system access mode used when creating
316 these directories. Takes an access
317 mode in octal notation. Defaults to
318 0755.</para></listitem>
322 <term><varname>TimeoutSec=</varname></term>
323 <listitem><para>Configures the time to
324 wait for the mount command to
325 finish. If a command does not exit
326 within the configured time, the mount
327 will be considered failed and be shut
328 down again. All commands still running
329 will be terminated forcibly via
330 <constant>SIGTERM</constant>, and after another delay of
331 this time with <constant>SIGKILL</constant>. (See
332 <option>KillMode=</option> in
333 <citerefentry><refentrytitle>systemd.kill</refentrytitle><manvolnum>5</manvolnum></citerefentry>.)
334 Takes a unit-less value in seconds, or
335 a time span value such as "5min
336 20s". Pass 0 to disable the timeout
337 logic. The default value is set from the manager configuration
338 file's <varname>DefaultTimeoutStart=</varname> variable.</para></listitem>
343 <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>
345 <citerefentry><refentrytitle>systemd.kill</refentrytitle><manvolnum>5</manvolnum></citerefentry>
346 for more settings.</para>
350 <title>See Also</title>
352 <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
353 <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
354 <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
355 <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
356 <citerefentry><refentrytitle>systemd.kill</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
357 <citerefentry><refentrytitle>systemd.resource-control</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
358 <citerefentry><refentrytitle>systemd.service</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
359 <citerefentry><refentrytitle>systemd.device</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
360 <citerefentry project='man-pages'><refentrytitle>proc</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
361 <citerefentry><refentrytitle>mount</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
362 <citerefentry><refentrytitle>systemd-fstab-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
363 <citerefentry><refentrytitle>systemd.directives</refentrytitle><manvolnum>7</manvolnum></citerefentry>