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7 This file is part of systemd.
9 Copyright 2010 Lennart Poettering
11 systemd is free software; you can redistribute it and/or modify it
12 under the terms of the GNU Lesser General Public License as published by
13 the Free Software Foundation; either version 2.1 of the License, or
14 (at your option) any later version.
16 systemd is distributed in the hope that it will be useful, but
17 WITHOUT ANY WARRANTY; without even the implied warranty of
18 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
19 Lesser General Public License for more details.
21 You should have received a copy of the GNU Lesser General Public License
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25 <refentry id=
"systemd.service">
27 <title>systemd.service
</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.service
</refentrytitle>
42 <manvolnum>5</manvolnum>
46 <refname>systemd.service
</refname>
47 <refpurpose>systemd service configuration files
</refpurpose>
51 <para><filename>systemd.service
</filename></para>
55 <title>Description
</title>
57 <para>A unit configuration file whose name ends in
58 <filename>.service
</filename> encodes information
59 about a process 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
<literal>[Unit]
</literal> and
68 <literal>[Install]
</literal> sections. The service
69 specific configuration options are configured in the
70 <literal>[Service]
</literal> section.
</para>
72 <para>Additional options are listed in
73 <citerefentry><refentrytitle>systemd.exec
</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
74 which define the execution environment the commands
75 are executed in.
</para>
77 <para>Unless
<varname>DefaultDependencies=
</varname>
78 is set to
<option>false
</option>, service units will
79 implicitly have dependencies of type
80 <varname>Requires=
</varname> and
81 <varname>After=
</varname> on
82 <filename>basic.target
</filename> as well as
83 dependencies of type
<varname>Conflicts=
</varname> and
84 <varname>Before=
</varname> on
85 <filename>shutdown.target
</filename>. These ensure
86 that normal service units pull in basic system
87 initialization, and are terminated cleanly prior to
88 system shutdown. Only services involved with early
89 boot or late system shutdown should disable this
92 <para>If a service is requested under a certain name
93 but no unit configuration file is found, systemd looks
94 for a SysV init script by the same name (with the
95 <filename>.service
</filename> suffix removed) and
96 dynamically creates a service unit from that
97 script. This is useful for compatibility with
98 SysV. Note that this compatibility is quite
99 comprehensive but not
100%. For details about the
100 incomptibilities see the
<ulink
101 url=
"http://www.freedesktop.org/wiki/Software/systemd/Incompatibilities">Incompatibilities
102 with SysV
</ulink> document.
107 <title>Options
</title>
109 <para>Service files must include a
110 <literal>[Service]
</literal> section, which carries
111 information about the service and the process it
112 supervises. A number of options that may be used in
113 this section are shared with other unit types. These
114 options are documented in
115 <citerefentry><refentrytitle>systemd.exec
</refentrytitle><manvolnum>5</manvolnum></citerefentry>. The
116 options specific to the
<literal>[Service]
</literal>
117 section of service units are the following:
</para>
121 <term><varname>Type=
</varname></term>
123 <listitem><para>Configures the process
124 start-up type for this service
125 unit. One of
<option>simple
</option>,
126 <option>forking
</option>,
127 <option>oneshot
</option>,
128 <option>dbus
</option>,
129 <option>notify
</option> or
130 <option>idle
</option>.
</para>
133 <option>simple
</option> (the default
134 value if
<varname>BusName=
</varname>
135 is not specified) it is expected that
136 the process configured with
137 <varname>ExecStart=
</varname> is the
138 main process of the service. In this
139 mode, if the process offers
140 functionality to other processes on
141 the system its communication channels
142 should be installed before the daemon
143 is started up (e.g. sockets set up by
144 systemd, via socket activation), as
145 systemd will immediately proceed
146 starting follow-up units.
</para>
149 <option>forking
</option> it is
150 expected that the process configured
151 with
<varname>ExecStart=
</varname>
152 will call
<function>fork()
</function>
153 as part of its start-up. The parent process is
154 expected to exit when start-up is
155 complete and all communication
156 channels set up. The child continues
157 to run as the main daemon
158 process. This is the behaviour of
159 traditional UNIX daemons. If this
160 setting is used, it is recommended to
162 <varname>PIDFile=
</varname> option, so
163 that systemd can identify the main
164 process of the daemon. systemd will
165 proceed starting follow-up units as
166 soon as the parent process
170 <option>oneshot
</option> is similar
171 to
<option>simple
</option>, however
172 it is expected that the process has to
173 exit before systemd starts follow-up
174 units.
<varname>RemainAfterExit=
</varname>
175 is particularly useful for this type
179 <option>dbus
</option> is similar to
180 <option>simple
</option>, however it is
181 expected that the daemon acquires a
182 name on the D-Bus bus, as configured
184 <varname>BusName=
</varname>. systemd
185 will proceed starting follow-up units
186 after the D-Bus bus name has been
187 acquired. Service units with this
188 option configured implicitly gain
190 <filename>dbus.socket
</filename>
191 unit. This type is the default if
192 <varname>BusName=
</varname> is
196 <option>notify
</option> is similar to
197 <option>simple
</option>, however it is
198 expected that the daemon sends a
199 notification message via
200 <citerefentry><refentrytitle>sd_notify
</refentrytitle><manvolnum>3</manvolnum></citerefentry>
201 or an equivalent call when it finished
202 starting up. systemd will proceed
203 starting follow-up units after this
204 notification message has been sent. If
206 <varname>NotifyAccess=
</varname> (see
207 below) should be set to open access to
208 the notification socket provided by
210 <varname>NotifyAccess=
</varname> is
211 not set, it will be implicitly set to
212 <option>main
</option>.
</para>
215 <option>idle
</option> is very similar
216 to
<option>simple
</option>, however
217 actual execution of a the service
218 binary is delayed until all jobs are
219 dispatched. This may be used to avoid
220 interleaving of output of shell
221 services with the status output on the
227 <term><varname>RemainAfterExit=
</varname></term>
229 <listitem><para>Takes a boolean value
230 that specifies whether the service
231 shall be considered active even when
232 all its processes exited. Defaults to
233 <option>no
</option>.
</para>
238 <term><varname>GuessMainPID=
</varname></term>
240 <listitem><para>Takes a boolean value
241 that specifies whether systemd should
242 try to guess the main PID of a service
243 should if it cannot be determined
244 reliably. This option is ignored
245 unless
<option>Type=forking
</option>
246 is set and
<option>PIDFile=
</option>
247 is unset because for the other types
248 or with an explicitly configured PID
249 file the main PID is always known. The
250 guessing algorithm might come to
251 incorrect conclusions if a daemon
252 consists of more than one process. If
253 the main PID cannot be determined
254 failure detection and automatic
255 restarting of a service will not work
256 reliably. Defaults to
257 <option>yes
</option>.
</para>
262 <term><varname>PIDFile=
</varname></term>
264 <listitem><para>Takes an absolute file
265 name pointing to the PID file of this
266 daemon. Use of this option is
267 recommended for services where
268 <varname>Type=
</varname> is set to
269 <option>forking
</option>. systemd will
270 read the PID of the main process of
271 the daemon after start-up of the
272 service. systemd will not write to the
273 file configured here.
</para>
278 <term><varname>BusName=
</varname></term>
280 <listitem><para>Takes a D-Bus bus
281 name, where this service is reachable
282 as. This option is mandatory for
284 <varname>Type=
</varname> is set to
285 <option>dbus
</option>, but its use
286 is otherwise recommended as well if
287 the process takes a name on the D-Bus
293 <term><varname>ExecStart=
</varname></term>
294 <listitem><para>Takes a command line
295 that is executed when this service
296 shall be started up. The first token
297 of the command line must be an
298 absolute file name, then followed by
299 arguments for the process. It is
300 mandatory to set this option for all
301 services. This option may not be
302 specified more than once, except when
303 <varname>Type=oneshot
</varname> is
304 used in which case more than one
305 <varname>ExecStart=
</varname> line is
306 accepted which are then invoked one by
307 one, sequentially in the order they
308 appear in the unit file.
</para>
310 <para>Optionally, if the absolute file
311 name is prefixed with
312 <literal>@
</literal>, the second token
314 <literal>argv[
0]
</literal> to the
315 executed process, followed by the
316 further arguments specified. If the
317 first token is prefixed with
318 <literal>-
</literal> an exit code of
319 the command normally considered a
320 failure (i.e. non-zero exit status or
321 abnormal exit due to signal) is ignored
322 and considered success. If both
323 <literal>-
</literal> and
324 <literal>@
</literal> are used for the
325 same command the former must precede
327 <varname>Type=forking
</varname> is
328 set, the process started via this
329 command line will be considered the
330 main process of the daemon. The
331 command line accepts % specifiers as
333 <citerefentry><refentrytitle>systemd.unit
</refentrytitle><manvolnum>5</manvolnum></citerefentry>.
</para>
335 <para>On top of that basic environment
336 variable substitution is
338 <literal>${FOO}
</literal> as part of a
339 word, or as word of its own on the
340 command line, in which case it will be
341 replaced by the value of the
342 environment variable including all
343 whitespace it contains, resulting in a
345 <literal>$FOO
</literal> as a separate
346 word on the command line, in which
347 case it will be replaced by the value
348 of the environment variable split up
349 at whitespace, resulting in no or more
350 arguments. Note that the first
351 argument (i.e. the program to execute)
352 may not be a variable, and must be a
353 literal and absolute path
354 name.
</para></listitem>
358 <term><varname>ExecStartPre=
</varname></term>
359 <term><varname>ExecStartPost=
</varname></term>
360 <listitem><para>Additional commands
361 that are executed before (resp. after)
363 <varname>ExecStart=
</varname>. Multiple
364 command lines may be concatenated in a
365 single directive, by separating them
366 by semicolons (these semicolons must
367 be passed as separate words). In that
368 case, the commands are executed one
370 serially. Alternatively, these
371 directives may be specified more than
372 once with the same effect. However,
373 the latter syntax is not recommended
374 for compatibility with parsers
376 <filename>.desktop
</filename> files.
377 Use of these settings is
378 optional. Specifier and environment
379 variable substitution is
380 supported.
</para></listitem>
384 <term><varname>ExecReload=
</varname></term>
385 <listitem><para>Commands to execute to
386 trigger a configuration reload in the
387 service. This argument takes multiple
388 command lines, following the same
389 scheme as pointed out for
390 <varname>ExecStartPre=
</varname>
391 above. Use of this setting is
392 optional. Specifier and environment
393 variable substitution is supported
394 here following the same scheme as for
395 <varname>ExecStart=
</varname>. One
396 special environment variable is set:
397 if known
<literal>$MAINPID
</literal> is
398 set to the main process of the
399 daemon, and may be used for command
400 lines like the following:
401 <command>/bin/kill -HUP
402 $MAINPID
</command>.
</para></listitem>
406 <term><varname>ExecStop=
</varname></term>
407 <listitem><para>Commands to execute to
408 stop the service started via
409 <varname>ExecStart=
</varname>. This
410 argument takes multiple command lines,
411 following the same scheme as pointed
413 <varname>ExecStartPre=
</varname>
414 above. Use of this setting is
415 optional. All processes remaining for
416 a service after the commands
417 configured in this option are run are
418 terminated according to the
419 <varname>KillMode=
</varname> setting
420 (see below). If this option is not
421 specified the process is terminated
422 right-away when service stop is
423 requested. Specifier and environment
424 variable substitution is supported
426 <literal>$MAINPID
</literal>, see
427 above).
</para></listitem>
431 <term><varname>ExecStopPost=
</varname></term>
432 <listitem><para>Additional commands
433 that are executed after the service
434 was stopped using the commands
436 <varname>ExecStop=
</varname>. This
437 argument takes multiple command lines,
438 following the same scheme as pointed
440 <varname>ExecStartPre
</varname>. Use
442 optional. Specifier and environment
443 variable substitution is
444 supported.
</para></listitem>
448 <term><varname>RestartSec=
</varname></term>
449 <listitem><para>Configures the time to
450 sleep before restarting a service (as
452 <varname>Restart=
</varname>). Takes a
453 unit-less value in seconds, or a time
454 span value such as
"5min
456 100ms.
</para></listitem>
460 <term><varname>TimeoutSec=
</varname></term>
461 <listitem><para>Configures the time to
462 wait for start-up and stop. If a
463 daemon service does not signal
464 start-up completion within the
465 configured time the service will be
466 considered failed and be shut down
467 again. If a service is asked to stop
468 but does not terminate in the
469 specified time it will be terminated
470 forcibly via SIGTERM, and after
471 another delay of this time with
473 <varname>KillMode=
</varname>
474 below.) Takes a unit-less value in seconds, or a
475 time span value such as
"5min
476 20s". Pass
0 to disable the timeout
478 90s, except when
<varname>Type=oneshot
</varname> is
479 used in which case the timeout
480 is disabled by default.
</para></listitem>
484 <term><varname>WatchdogSec=
</varname></term>
485 <listitem><para>Configures the
486 watchdog timeout for a service. This
487 is activated when the start-up is
488 completed. The service must call
489 <citerefentry><refentrytitle>sd_notify
</refentrytitle><manvolnum>3</manvolnum></citerefentry>
490 regularly with
"WATCHDOG=1" (i.e. the
491 "keep-alive ping"). If the time
492 between two such calls is larger than
493 the configured time then the service
494 is placed in a failure state. By
495 setting
<varname>Restart=
</varname> to
496 <option>on-failure
</option> or
497 <option>always
</option> the service
498 will be automatically restarted. The
499 time configured here will be passed to
500 the executed service process in the
501 <varname>WATCHDOG_USEC=
</varname>
502 environment variable. This allows
503 daemons to automatically enable the
504 keep-alive pinging logic if watchdog
505 support is enabled for the service. If
507 <varname>NotifyAccess=
</varname> (see
508 below) should be set to open access to
509 the notification socket provided by
511 <varname>NotifyAccess=
</varname> is
512 not set, it will be implicitly set to
513 <option>main
</option>. Defaults to
0,
515 feature.
</para></listitem>
519 <term><varname>Restart=
</varname></term>
520 <listitem><para>Configures whether the
521 main service process shall be
522 restarted when it exits. Takes one of
524 <option>on-success
</option>,
525 <option>on-failure
</option>,
526 <option>on-abort
</option> or
527 <option>always
</option>. If set to
528 <option>no
</option> (the default) the
529 service will not be restarted when it
531 <option>on-success
</option> it will be
532 restarted only when it exited cleanly,
533 i.e. terminated with an exit code of
535 <option>on-failure
</option> it will be
536 restarted only when it exited with an
537 exit code not equalling
0, when
538 terminated by a signal, when an
539 operation times out or when the
540 configured watchdog timeout is
542 <option>on-abort
</option> it will be
543 restarted only if it exits due to
544 reception of an uncaught signal. If
545 set to
<option>always
</option> the
546 service will be restarted regardless
547 whether it exited cleanly or not,
548 got terminated abnormally by a
549 signal or hit a timeout.
</para></listitem>
553 <term><varname>PermissionsStartOnly=
</varname></term>
554 <listitem><para>Takes a boolean
555 argument. If true, the permission
556 related execution options as
558 <varname>User=
</varname> and similar
560 <citerefentry><refentrytitle>systemd.exec
</refentrytitle><manvolnum>5</manvolnum></citerefentry>
561 for more information) are only applied
562 to the process started with
563 <varname>ExecStart=
</varname>, and not
565 <varname>ExecStartPre=
</varname>,
566 <varname>ExecStartPost=
</varname>,
567 <varname>ExecReload=
</varname>,
568 <varname>ExecStop=
</varname>,
569 <varname>ExecStopPost=
</varname>
570 commands. If false, the setting is
571 applied to all configured commands the
572 same way. Defaults to
573 false.
</para></listitem>
577 <term><varname>RootDirectoryStartOnly=
</varname></term>
578 <listitem><para>Takes a boolean
579 argument. If true, the root directory
580 as configured with the
581 <varname>RootDirectory=
</varname>
583 <citerefentry><refentrytitle>systemd.exec
</refentrytitle><manvolnum>5</manvolnum></citerefentry>
584 for more information) is only applied
585 to the process started with
586 <varname>ExecStart=
</varname>, and not
588 <varname>ExecStartPre=
</varname>,
589 <varname>ExecStartPost=
</varname>,
590 <varname>ExecReload=
</varname>,
591 <varname>ExecStop=
</varname>,
592 <varname>ExecStopPost=
</varname>
593 commands. If false, the setting is
594 applied to all configured commands the
595 same way. Defaults to
596 false.
</para></listitem>
600 <term><varname>KillMode=
</varname></term>
601 <listitem><para>Specifies how
602 processes of this service shall be
604 <option>control-group
</option>,
605 <option>process
</option>,
606 <option>none
</option>.
</para>
609 <option>control-group
</option> all
610 remaining processes in the control
611 group of this service will be
612 terminated on service stop, after the
613 stop command (as configured with
614 <varname>ExecStop=
</varname>) is
616 <option>process
</option> only the main
617 process itself is killed. If set to
618 <option>none
</option> no process is
619 killed. In this case only the stop
620 command will be executed on service
621 stop, but no process be killed
622 otherwise. Processes remaining alive
623 after stop are left in their control
624 group and the control group continues
625 to exist after stop unless it is
627 <option>control-group
</option>.
</para>
629 <para>Processes will first be
630 terminated via SIGTERM (unless the
631 signal to send is changed via
632 <varname>KillSignal=
</varname>). If
633 then after a delay (configured via the
634 <varname>TimeoutSec=
</varname> option)
635 processes still remain, the
636 termination request is repeated with
637 the SIGKILL signal (unless this is
639 <varname>SendSIGKILL=
</varname>
641 <citerefentry><refentrytitle>kill
</refentrytitle><manvolnum>2</manvolnum></citerefentry>
643 information.
</para></listitem>
647 <term><varname>KillSignal=
</varname></term>
648 <listitem><para>Specifies which signal
649 to use when killing a
650 service. Defaults to SIGTERM.
655 <term><varname>SendSIGKILL=
</varname></term>
656 <listitem><para>Specifies whether to
657 send SIGKILL to remaining processes
658 after a timeout, if the normal
659 shutdown procedure left processes of
660 the service around. Takes a boolean
661 value. Defaults to
"yes".
666 <term><varname>NonBlocking=
</varname></term>
667 <listitem><para>Set O_NONBLOCK flag
668 for all file descriptors passed via
669 socket-based activation. If true, all
670 file descriptors
>=
3 (i.e. all except
671 STDIN/STDOUT/STDERR) will have
672 the O_NONBLOCK flag set and hence are in
673 non-blocking mode. This option is only
674 useful in conjunction with a socket
675 unit, as described in
676 <citerefentry><refentrytitle>systemd.socket
</refentrytitle><manvolnum>5</manvolnum></citerefentry>. Defaults
677 to false.
</para></listitem>
681 <term><varname>NotifyAccess=
</varname></term>
682 <listitem><para>Controls access to the
683 service status notification socket, as
685 <citerefentry><refentrytitle>sd_notify
</refentrytitle><manvolnum>3</manvolnum></citerefentry>
687 <option>none
</option> (the default),
688 <option>main
</option> or
689 <option>all
</option>. If
690 <option>none
</option> no daemon status
691 updates are accepted from the service
692 processes, all status update messages
693 are ignored. If
<option>main
</option>
694 only service updates sent from the
695 main process of the service are
696 accepted. If
<option>all
</option> all
697 services updates from all members of
698 the service's control group are
699 accepted. This option should be set to
700 open access to the notification socket
702 <varname>Type=notify
</varname> or
703 <varname>WatchdogUsec=
</varname> (see
704 above). If those options are used but
705 <varname>NotifyAccess=
</varname> not
706 configured it will be implicitly set
708 <option>main
</option>.
</para></listitem>
712 <term><varname>Sockets=
</varname></term>
713 <listitem><para>Specifies the name of
714 the socket units this service shall
715 inherit the sockets from when the
716 service is started. Normally it
717 should not be necessary to use this
718 setting as all sockets whose unit
719 shares the same name as the service
720 (ignoring the different suffix of course)
721 are passed to the spawned
724 <para>Note that the same socket may be
725 passed to multiple processes at the
726 same time. Also note that a different
727 service may be activated on incoming
728 traffic than inherits the sockets. Or
730 <varname>Service=
</varname> setting of
731 <filename>.socket
</filename> units
732 doesn't have to match the inverse of the
733 <varname>Sockets=
</varname> setting of
734 the
<filename>.service
</filename> it
735 refers to.
</para></listitem>
739 <term><varname>StartLimitInterval=
</varname></term>
740 <term><varname>StartLimitBurst=
</varname></term>
742 <listitem><para>Configure service
743 start rate limiting. By default
744 services which are started more often
745 than
5 times within
10s are not
746 permitted to start any more times
747 until the
10s interval ends. With
748 these two options this rate limiting
750 <varname>StartLimitInterval=
</varname>
751 to configure the checking interval
752 (defaults to
10s, set to
0 to disable
753 any kind of rate limiting). Use
754 <varname>StartLimitBurst=
</varname> to
755 configure how many starts per interval
756 are allowed (defaults to
5). These
757 configuration options are particularly
758 useful in conjunction with
759 <varname>Restart=
</varname>.
</para></listitem>
763 <term><varname>StartLimitAction=
</varname></term>
765 <listitem><para>Configure the action
766 to take if the rate limit configured
768 <varname>StartLimitInterval=
</varname>
770 <varname>StartLimitBurst=
</varname> is
772 <option>none
</option>,
773 <option>reboot
</option>,
774 <option>reboot-force
</option> or
775 <option>reboot-immediate
</option>. If
776 <option>none
</option> is set,
777 hitting the rate limit will trigger no
778 action besides that the start will not
780 permitted.
<option>reboot
</option>
781 causes a reboot following the normal
782 shutdown procedure (i.e. equivalent to
783 <command>systemctl reboot
</command>),
784 <option>reboot-force
</option> causes
785 an forced reboot which will terminate
786 all processes forcibly but should
787 cause no dirty file systems on reboot
788 (i.e. equivalent to
<command>systemctl
789 reboot -f
</command>) and
790 <option>reboot-immediate
</option>
791 causes immediate execution of the
792 <citerefentry><refentrytitle>reboot
</refentrytitle><manvolnum>2</manvolnum></citerefentry>
793 system call, which might result in
794 data loss. Defaults to
795 <option>none
</option>.
</para></listitem>
802 <title>Compatibility Options
</title>
804 <para>The following options are also available in the
805 <literal>[Service]
</literal> section, but exist purely
806 for compatibility reasons and should not be used in
807 newly written service files.
</para>
811 <term><varname>SysVStartPriority=
</varname></term>
812 <listitem><para>Set the SysV start
813 priority to use to order this service
814 in relation to SysV services lacking
815 LSB headers. This option is only
816 necessary to fix ordering in relation
817 to legacy SysV services, that have no
818 ordering information encoded in the
819 script headers. As such it should only
820 be used as temporary compatibility
821 option, and not be used in new unit
822 files. Almost always it is a better
823 choice to add explicit ordering
825 <varname>After=
</varname> or
826 <varname>Before=
</varname>,
827 instead. For more details see
828 <citerefentry><refentrytitle>systemd.unit
</refentrytitle><manvolnum>5</manvolnum></citerefentry>. If
829 used, pass an integer value in the
830 range
0-
99.
</para></listitem>
834 <term><varname>FsckPassNo=
</varname></term>
835 <listitem><para>Set the fsck passno
836 priority to use to order this service
837 in relation to other file system
838 checking services. This option is only
839 necessary to fix ordering in relation
840 to fsck jobs automatically created for
841 all
<filename>/etc/fstab
</filename>
842 entries with a value in the fs_passno
843 column
> 0. As such it should only be
844 used as option for fsck
845 services. Almost always it is a better
846 choice to add explicit ordering
848 <varname>After=
</varname> or
849 <varname>Before=
</varname>,
850 instead. For more details see
851 <citerefentry><refentrytitle>systemd.unit
</refentrytitle><manvolnum>5</manvolnum></citerefentry>. If
852 used, pass an integer value in the
854 <filename>/etc/fstab
</filename>'s
855 fs_passno column. See
856 <citerefentry><refentrytitle>fstab
</refentrytitle><manvolnum>5</manvolnum></citerefentry>
857 for details.
</para></listitem>
864 <title>See Also
</title>
866 <citerefentry><refentrytitle>systemd
</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
867 <citerefentry><refentrytitle>systemctl
</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
868 <citerefentry><refentrytitle>systemd.unit
</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
869 <citerefentry><refentrytitle>systemd.exec
</refentrytitle><manvolnum>5</manvolnum></citerefentry>