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2 <!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
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6 This file is part of systemd.
8 Copyright 2010 Lennart Poettering
10 systemd is free software; you can redistribute it and/or modify it
11 under the terms of the GNU Lesser General Public License as published by
12 the Free Software Foundation; either version 2.1 of the License, or
13 (at your option) any later version.
15 systemd is distributed in the hope that it will be useful, but
16 WITHOUT ANY WARRANTY; without even the implied warranty of
17 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
18 Lesser General Public License for more details.
20 You should have received a copy of the GNU Lesser General Public License
21 along with systemd; If not, see <http://www.gnu.org/licenses/>.
24 <refentry id="systemctl">
27 <title>systemctl</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>systemctl</refentrytitle>
42 <manvolnum>1</manvolnum>
46 <refname>systemctl</refname>
47 <refpurpose>Control the systemd system and service manager</refpurpose>
52 <command>systemctl <arg choice="opt" rep="repeat">OPTIONS</arg> <arg choice="req">COMMAND</arg> <arg choice="opt" rep="repeat">NAME</arg></command>
57 <title>Description</title>
59 <para><command>systemctl</command> may be used to
60 introspect and control the state of the
61 <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>
62 system and service manager.</para>
66 <title>Options</title>
68 <para>The following options are understood:</para>
72 <term><option>--help</option></term>
73 <term><option>-h</option></term>
75 <listitem><para>Prints a short help
76 text and exits.</para></listitem>
80 <term><option>--version</option></term>
82 <listitem><para>Prints a short version
83 string and exits.</para></listitem>
87 <term><option>--type=</option></term>
88 <term><option>-t</option></term>
90 <listitem><para>When listing units,
91 limit display to certain unit
92 types. If not specified units of all
93 types will be shown. The argument
94 should be a unit type name such as
95 <option>service</option>,
96 <option>socket</option> and
97 similar.</para></listitem>
101 <term><option>--property=</option></term>
102 <term><option>-p</option></term>
104 <listitem><para>When showing
105 unit/job/manager properties, limit
106 display to certain properties as
107 specified as argument. If not
108 specified all set properties are
109 shown. The argument should be a
110 property name, such as
111 <literal>MainPID</literal>. If
112 specified more than once all
113 properties with the specified names
114 are shown.</para></listitem>
118 <term><option>--all</option></term>
119 <term><option>-a</option></term>
121 <listitem><para>When listing units,
122 show all units, regardless of their
123 state, including inactive units. When
124 showing unit/job/manager properties,
125 show all properties regardless whether
126 they are set or not.</para></listitem>
130 <term><option>--failed</option></term>
132 <listitem><para>When listing units,
133 show only failed units. Do not confuse
135 <option>--fail</option>.</para></listitem>
139 <term><option>--full</option></term>
141 <listitem><para>Do not ellipsize unit
142 names and truncate unit descriptions
144 <command>list-units</command> and
145 <command>list-jobs</command>.</para></listitem>
149 <term><option>--fail</option></term>
151 <listitem><para>If the requested
152 operation conflicts with a pending
153 unfinished job, fail the command. If
154 this is not specified the requested
155 operation will replace the pending job,
156 if necessary. Do not confuse
158 <option>--failed</option>.</para></listitem>
162 <term><option>--ignore-dependencies</option></term>
164 <listitem><para>When enqueuing a new
165 job ignore all its dependencies and
166 execute it immediately. If passed no
167 required units of the unit passed will
168 be pulled in, and no ordering
169 dependencies will be honoured. This is
170 mostly a debugging and rescue tool for
171 the administrator and should not be
173 applications.</para></listitem>
177 <term><option>--quiet</option></term>
178 <term><option>-q</option></term>
180 <listitem><para>Suppress output to
182 <command>snapshot</command>,
183 <command>is-active</command>,
184 <command>enable</command> and
185 <command>disable</command>.</para></listitem>
189 <term><option>--no-block</option></term>
191 <listitem><para>Do not synchronously wait for
192 the requested operation to finish. If this is
193 not specified the job will be verified,
194 enqueued and <command>systemctl</command> will
195 wait until it is completed. By passing this
196 argument it is only verified and
197 enqueued.</para></listitem>
201 <term><option>--no-legend</option></term>
203 <listitem><para>Do not print a legend, i.e.
204 the column headers and the footer with hints.
209 <term><option>--no-pager</option></term>
211 <listitem><para>Do not pipe output into a
212 pager.</para></listitem>
216 <term><option>--system</option></term>
218 <listitem><para>Talk to the systemd
219 system manager. (Default)</para></listitem>
223 <term><option>--user</option></term>
225 <listitem><para>Talk to the systemd
226 manager of the calling user.</para></listitem>
230 <term><option>--order</option></term>
231 <term><option>--require</option></term>
233 <listitem><para>When used in
235 <command>dot</command> command (see
236 below), selects which dependencies are
237 shown in the dependency graph. If
238 <option>--order</option> is passed
239 only dependencies of type
240 <varname>After=</varname> or
241 <varname>Before=</varname> are
242 shown. If <option>--require</option>
243 is passed only dependencies of type
244 <varname>Requires=</varname>,
245 <varname>RequiresOverridable=</varname>,
246 <varname>Requisite=</varname>,
247 <varname>RequisiteOverridable=</varname>,
248 <varname>Wants=</varname> and
249 <varname>Conflicts=</varname> are
250 shown. If neither is passed, shows
251 dependencies of all these
252 types.</para></listitem>
256 <term><option>--no-wall</option></term>
258 <listitem><para>Don't send wall
260 halt, power-off, reboot.</para></listitem>
264 <term><option>--global</option></term>
266 <listitem><para>When used with
267 <command>enable</command> and
268 <command>disable</command>, operate on the
269 global user configuration
270 directory, thus enabling or disabling
271 a unit file globally for all future
272 logins of all users.</para></listitem>
276 <term><option>--no-reload</option></term>
278 <listitem><para>When used with
279 <command>enable</command> and
280 <command>disable</command>, do not
281 implicitly reload daemon configuration
283 changes.</para></listitem>
287 <term><option>--no-ask-password</option></term>
289 <listitem><para>When used with
290 <command>start</command> and related
291 commands, disables asking for
292 passwords. Background services may
293 require input of a password or
294 passphrase string, for example to
295 unlock system hard disks or
296 cryptographic certificates. Unless
297 this option is specified and the
298 command is invoked from a terminal
299 <command>systemctl</command> will
300 query the user on the terminal for the
301 necessary secrets. Use this option to
302 switch this behavior off. In this case
303 the password must be supplied by some
304 other means (for example graphical
305 password agents) or the service might
306 fail. This also disables querying the
307 user for authentication for privileged
308 operations.</para></listitem>
312 <term><option>--kill-who=</option></term>
314 <listitem><para>When used with
315 <command>kill</command>, choose which
316 processes to kill. Must be one of
317 <option>main</option>,
318 <option>control</option> or
319 <option>all</option> to select whether
320 to kill only the main process of the
321 unit, the control process or all
322 processes of the unit. If omitted
324 <option>all</option>.</para></listitem>
328 <term><option>--signal=</option></term>
329 <term><option>-s</option></term>
331 <listitem><para>When used with
332 <command>kill</command>, choose which
333 signal to send to selected
334 processes. Must be one of the well
335 known signal specifiers such as
336 SIGTERM, SIGINT or SIGSTOP. If
338 <option>SIGTERM</option>.</para></listitem>
342 <term><option>--force</option></term>
343 <term><option>-f</option></term>
345 <listitem><para>When used with
346 <command>enable</command>, overwrite any
348 symlinks.</para></listitem>
350 <listitem><para>When used with
351 <command>halt</command>,
352 <command>poweroff</command>,
353 <command>reboot</command> or
354 <command>kexec</command> execute the
355 selected operation without shutting
356 down all units. However, all processes
357 will be killed forcibly and all file
358 systems are unmounted or remounted
359 read-only. This is hence a drastic but
360 relatively safe option to request an
362 <option>--force</option> is specified
363 twice for these operations, they will
364 be executed immediately without
365 terminating any processes or umounting
366 any file systems. Warning: specifying
367 <option>--force</option> twice with
368 any of these operations might result
369 in data loss.</para></listitem>
373 <term><option>--root=</option></term>
375 <listitem><para>When used with
376 <command>enable</command>/<command>disable</command>/<command>is-enabled</command> (and
377 related commands), use alternative
378 root path when looking for unit
379 files.</para></listitem>
383 <term><option>--runtime</option></term>
385 <listitem><para>When used with
386 <command>enable</command>/<command>disable</command>/<command>is-enabled</command> (and related commands), make
387 changes only temporarily, so that they
388 are dropped on the next reboot. This
389 will have the effect that changes are
390 not made in subdirectories of
391 <filename>/etc</filename> but in
392 <filename>/run</filename>, with
393 identical immediate effects, however,
394 since the latter is lost on reboot,
396 too.</para></listitem>
400 <term><option>-H</option></term>
401 <term><option>--host</option></term>
403 <listitem><para>Execute operation
404 remotely. Specify a hostname, or
405 username and hostname separated by @,
406 to connect to. This will use SSH to
407 talk to the remote systemd
408 instance.</para></listitem>
412 <term><option>-P</option></term>
413 <term><option>--privileged</option></term>
415 <listitem><para>Acquire privileges via
416 PolicyKit before executing the
417 operation.</para></listitem>
421 <term><option>--lines=</option></term>
422 <term><option>-n</option></term>
424 <listitem><para>When used with
425 <command>status</command> controls the
426 number of journal lines to show,
427 counting from the most recent
428 ones. Takes a positive integer
429 argument. Defaults to
430 10.</para></listitem>
434 <term><option>--follow</option></term>
435 <term><option>-f</option></term>
437 <listitem><para>When used with
438 <command>status</command> continously
439 prints new journal entries as they are
441 journal.</para></listitem>
445 <term><option>--output=</option></term>
446 <term><option>-o</option></term>
448 <listitem><para>When used with
449 <command>status</command> controls the
450 formatting of the journal entries that
451 are shown. For the available choices
453 <citerefentry><refentrytitle>journalctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>. Defaults
455 <literal>short</literal>.</para></listitem>
460 <para>The following commands are understood:</para>
464 <term><command>list-units</command></term>
466 <listitem><para>List known units.</para></listitem>
469 <term><command>start [NAME...]</command></term>
471 <listitem><para>Start (activate) one
472 or more units specified on the command
473 line.</para></listitem>
476 <term><command>stop [NAME...]</command></term>
478 <listitem><para>Stop (deactivate) one
479 or more units specified on the command
480 line.</para></listitem>
483 <term><command>reload [NAME...]</command></term>
485 <listitem><para>Asks all units listed
486 on the command line to reload their
487 configuration. Note that this will
488 reload the service-specific
489 configuration, not the unit
490 configuration file of systemd. If you
491 want systemd to reload the
492 configuration file of a unit use the
493 <command>daemon-reload</command>
494 command. In other words: for the
495 example case of Apache, this will
497 <filename>httpd.conf</filename> in the
499 <filename>apache.service</filename>
500 systemd unit file. </para>
502 <para>This command should not be
504 <command>daemon-reload</command> or
505 <command>load</command>
506 commands.</para></listitem>
510 <term><command>restart [NAME...]</command></term>
512 <listitem><para>Restart one or more
513 units specified on the command
514 line. If the units are not running yet
516 started.</para></listitem>
519 <term><command>try-restart [NAME...]</command></term>
521 <listitem><para>Restart one or more
522 units specified on the command
523 line if the units are running. Do
524 nothing if units are not running.
525 Note that for compatibility
526 with Red Hat init scripts
527 <command>condrestart</command> is
528 equivalent to this command.</para></listitem>
531 <term><command>reload-or-restart [NAME...]</command></term>
533 <listitem><para>Reload one or more
534 units if they support it. If not,
535 restart them instead. If the units
536 are not running yet they will be
537 started.</para></listitem>
540 <term><command>reload-or-try-restart [NAME...]</command></term>
542 <listitem><para>Reload one or more
543 units if they support it. If not,
544 restart them instead. Do nothing if
545 the units are not running. Note that
546 for compatibility with SysV init
548 <command>force-reload</command> is
550 command.</para></listitem>
553 <term><command>isolate [NAME]</command></term>
555 <listitem><para>Start the unit
556 specified on the command line and its
557 dependencies and stop all others.</para>
559 <para>This is similar to changing the
560 runlevel in a traditional init system. The
561 <command>isolate</command> command will
562 immediately stop processes that are not
563 enabled in the new unit, possibly including
564 the graphical environment or terminal you
565 are currently using.</para>
567 <para>Note that this works only on units
568 where <option>AllowIsolate=</option> is
570 <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>
571 for details.</para></listitem>
574 <term><command>kill [NAME...]</command></term>
576 <listitem><para>Send a signal to one
577 or more processes of the unit. Use
578 <option>--kill-who=</option> to select
579 which process to kill. Use
580 <option>--kill-mode=</option> to
581 select the kill mode and
582 <option>--signal=</option> to select
583 the signal to send.</para></listitem>
586 <term><command>is-active [NAME...]</command></term>
588 <listitem><para>Check whether any of
589 the specified units are active
590 (i.e. running). Returns an exit code
591 0 if at least one is active, non-zero
593 <option>--quiet</option> is specified
594 this will also print the current unit
595 state to STDOUT.</para></listitem>
598 <term><command>status [NAME...|PID...]</command></term>
600 <listitem><para>Show terse runtime
601 status information about one or more
602 units, followed by its most recent log
603 data from the journal. This function
604 is intended to generate human-readable
605 output. If you are looking for
606 computer-parsable output, use
607 <command>show</command> instead. If a
608 PID is passed information about the
609 unit the process of the PID belongs to
610 is shown.</para></listitem>
613 <term><command>show [NAME...|JOB...]</command></term>
615 <listitem><para>Show properties of one
616 or more units, jobs or the manager
617 itself. If no argument is specified
618 properties of the manager will be
619 shown. If a unit name is specified
620 properties of the unit is shown, and
621 if a job id is specified properties of
622 the job is shown. By default, empty
623 properties are suppressed. Use
624 <option>--all</option> to show those
625 too. To select specific properties to
627 <option>--property=</option>. This
628 command is intended to be used
629 whenever computer-parsable output is
631 <command>status</command> if you are
632 looking for formatted human-readable
633 output.</para></listitem>
636 <term><command>help [NAME...|PID...]</command></term>
638 <listitem><para>Show manual pages for
639 one or more units, if available. If a
640 PID is passed the manual pages for the
641 unit the process of the PID belongs to
642 is shown.</para></listitem>
645 <term><command>reset-failed [NAME...]</command></term>
647 <listitem><para>Reset the
648 '<literal>failed</literal>' state of the
649 specified units, or if no unit name is
650 passed of all units. When a unit fails
651 in some way (i.e. process exiting with
652 non-zero error code, terminating
653 abnormally or timing out) it will
654 automatically enter the
655 '<literal>failed</literal>' state and
656 its exit code and status is recorded
657 for introspection by the administrator
658 until the service is restarted or
660 command.</para></listitem>
664 <term><command>list-unit-files</command></term>
666 <listitem><para>List installed unit files.
671 <term><command>enable [NAME...]</command></term>
673 <listitem><para>Enable one or more
674 unit files, as specified on the
675 command line. This will create a
676 number of symlinks as encoded in the
677 <literal>[Install]</literal> sections
678 of the unit files. After the symlinks
679 have been created the systemd
680 configuration is reloaded (in a way
681 that is equivalent to
682 <command>daemon-reload</command>) to
683 ensure the changes are taken into
684 account immediately. Note that this
685 does not have the effect that any of
686 the units enabled are also started at
687 the same time. If this is desired a
688 separate <command>start</command>
689 command must be invoked for the
692 <para>This command will
693 print the actions executed. This
694 output may be suppressed by passing
695 <option>--quiet</option>.</para>
697 <para>Note that this operation creates
698 only the suggested symlinks for the
699 units. While this command is the
700 recommended way to manipulate the unit
701 configuration directory, the
702 administrator is free to make
703 additional changes manually, by
704 placing or removing symlinks in the
705 directory. This is particularly useful
706 to create configurations that deviate
707 from the suggested default
708 installation. In this case the
709 administrator must make sure to invoke
710 <command>daemon-reload</command>
711 manually as necessary, to ensure his
712 changes are taken into account.</para>
714 <para>Enabling units should not be
715 confused with starting (activating)
716 units, as done by the
717 <command>start</command>
718 command. Enabling and starting units
719 is orthogonal: units may be enabled
720 without being started and started
721 without being enabled. Enabling simply
722 hooks the unit into various suggested
723 places (for example, so that the unit
724 is automatically started on boot or
725 when a particular kind of hardware is
726 plugged in). Starting actually spawns
727 the daemon process (in case of service
728 units), or binds the socket (in case
729 of socket units), and so
732 <para>Depending on whether
733 <option>--system</option>,
734 <option>--user</option> or
735 <option>--global</option> is specified
736 this enables the unit for the system,
737 for the calling user only
738 or for all future logins of all
739 users. Note that in the latter case no
740 systemd daemon configuration is
746 <term><command>disable [NAME...]</command></term>
748 <listitem><para>Disables one or more
749 units. This removes all symlinks to
750 the specified unit files from the unit
751 configuration directory, and hence
752 undoes the changes made by
753 <command>enable</command>. Note
754 however that this removes
755 all symlinks to the unit files
756 (i.e. including manual additions), not
757 just those actually created by
758 <command>enable</command>. This call
759 implicitly reloads the systemd daemon
760 configuration after completing the
761 disabling of the units. Note that this
762 command does not implicitly stop the
763 units that is being disabled. If this
764 is desired an additional
765 <command>stop</command> command should
766 be executed afterwards.</para>
768 <para>This command will print the
769 actions executed. This output may be
770 suppressed by passing
771 <option>--quiet</option>.</para>
774 <para>This command honors
775 <option>--system</option>,
776 <option>--user</option>,
777 <option>--global</option> in a similar
779 <command>enable</command>.</para>
783 <term><command>is-enabled [NAME...]</command></term>
785 <listitem><para>Checks whether any of
786 the specified unit files is enabled
788 <command>enable</command>). Returns an
789 exit code of 0 if at least one is
790 enabled, non-zero otherwise. Prints
791 the current enable status. To suppress
793 <option>--quiet</option>.</para></listitem>
797 <term><command>reenable [NAME...]</command></term>
799 <listitem><para>Reenable one or more
800 unit files, as specified on the
801 command line. This is a combination of
802 <command>disable</command> and
803 <command>enable</command> and is
804 useful to reset the symlinks a unit is
805 enabled with to the defaults
807 <literal>[Install]</literal> section
808 of the unit file.</para>
813 <term><command>preset [NAME...]</command></term>
815 <listitem><para>Reset one or more unit
816 files, as specified on the command
817 line, to the defaults configured in
818 the preset policy files. This has the
820 <command>disable</command> or
821 <command>enable</command>, depending
822 how the unit is listed in the preset
823 files. For more information on preset
825 <citerefentry><refentrytitle>systemd.preset</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para>
830 <term><command>mask [NAME...]</command></term>
832 <listitem><para>Mask one or more unit
833 files, as specified on the command
834 line. This will link these units to
835 <filename>/dev/null</filename>, making
836 it impossible to start them. This is a stronger version
837 of <command>disable</command>, since
838 it prohibits all kinds of activation
839 of the unit, including manual
840 activation. Use this option with
846 <term><command>unmask [NAME...]</command></term>
848 <listitem><para>Unmask one or more
849 unit files, as specified on the
850 command line. This will undo the
852 <command>mask</command>.</para>
857 <term><command>link [NAME...]</command></term>
859 <listitem><para>Link a unit file that
860 is not in the unit file search paths
861 into the unit file search path. This
862 requires an absolute path to a unit
863 file. The effect of this can be undone
864 with <command>disable</command>. The
865 effect of this command is that a unit
866 file is available for
867 <command>start</command> and other
868 commands although it isn't installed
869 directly in the unit search
875 <term><command>load [NAME...]</command></term>
877 <listitem><para>Load one or more units
878 specified on the command line. This
879 will simply load their configuration
880 from disk, but not start them. To
881 start them you need to use the
882 <command>start</command> command which
883 will implicitly load a unit that has
884 not been loaded yet. Note that systemd
885 garbage collects loaded units that are
886 not active or referenced by an active
887 unit. This means that units loaded
888 this way will usually not stay loaded
889 for long. Also note that this command
890 cannot be used to reload unit
891 configuration. Use the
892 <command>daemon-reload</command>
893 command for that. All in all, this
894 command is of little use except for
896 <para>This command should not be
898 <command>daemon-reload</command> or
899 <command>reload</command>
900 commands.</para></listitem>
903 <term><command>list-jobs</command></term>
905 <listitem><para>List jobs that are in progress.</para></listitem>
908 <term><command>cancel [JOB...]</command></term>
910 <listitem><para>Cancel one or more
911 jobs specified on the command line by
913 IDs. If no job id is specified, cancel all pending jobs.</para></listitem>
916 <term><command>dump</command></term>
918 <listitem><para>Dump server
919 status. This will output a (usually
920 very long) human readable manager
921 status dump. Its format is subject to
922 change without notice and should not
924 applications.</para></listitem>
927 <term><command>dot</command></term>
929 <listitem><para>Generate textual
930 dependency graph description in dot
931 format for further processing with the
933 <citerefentry><refentrytitle>dot</refentrytitle><manvolnum>1</manvolnum></citerefentry>
934 tool. Use a command line like
935 <command>systemctl dot | dot -Tsvg >
936 systemd.svg</command> to generate a
937 graphical dependency tree. Unless
938 <option>--order</option> or
939 <option>--require</option> is passed
940 the generated graph will show both
941 ordering and requirement
942 dependencies.</para></listitem>
945 <term><command>snapshot [NAME]</command></term>
947 <listitem><para>Create a snapshot. If
948 a snapshot name is specified, the new
949 snapshot will be named after it. If
950 none is specified an automatic
951 snapshot name is generated. In either
952 case, the snapshot name used is
953 printed to STDOUT, unless
954 <option>--quiet</option> is
957 <para>A snapshot refers to a saved
958 state of the systemd manager. It is
959 implemented itself as a unit that is
960 generated dynamically with this
961 command and has dependencies on all
962 units active at the time. At a later
963 time the user may return to this state
965 <command>isolate</command> command on
966 the snapshot unit.</para></listitem>
968 <para>Snapshots are only useful for
969 saving and restoring which units are
970 running or are stopped, they do not
971 save/restore any other
972 state. Snapshots are dynamic and lost
976 <term><command>delete [NAME...]</command></term>
978 <listitem><para>Remove a snapshot
979 previously created with
980 <command>snapshot</command>.</para></listitem>
983 <term><command>daemon-reload</command></term>
985 <listitem><para>Reload systemd manager
986 configuration. This will reload all
987 unit files and recreate the entire
988 dependency tree. While the daemon is
989 reloaded, all sockets systemd listens
990 on on behalf of user configuration will
991 stay accessible.</para> <para>This
992 command should not be confused with
993 the <command>load</command> or
994 <command>reload</command>
995 commands.</para></listitem>
998 <term><command>daemon-reexec</command></term>
1000 <listitem><para>Reexecute the systemd
1001 manager. This will serialize the
1002 manager state, reexecute the process
1003 and deserialize the state again. This
1004 command is of little use except for
1005 debugging and package
1006 upgrades. Sometimes it might be
1007 helpful as a heavy-weight
1008 <command>daemon-reload</command>. While
1009 the daemon is reexecuted all sockets
1010 systemd listens on on behalf of user
1011 configuration will stay
1012 accessible.</para></listitem>
1015 <term><command>show-environment</command></term>
1017 <listitem><para>Dump the systemd
1018 manager environment block. The
1019 environment block will be dumped in
1020 straight-forward form suitable for
1021 sourcing into a shell script. This
1022 environment block will be passed to
1023 all processes the manager
1024 spawns.</para></listitem>
1027 <term><command>set-environment [NAME=VALUE...]</command></term>
1029 <listitem><para>Set one or more
1030 systemd manager environment variables,
1031 as specified on the command
1032 line.</para></listitem>
1035 <term><command>unset-environment [NAME...]</command></term>
1037 <listitem><para>Unset one or more
1038 systemd manager environment
1039 variables. If only a variable name is
1040 specified it will be removed
1041 regardless of its value. If a variable
1042 and a value are specified the variable
1043 is only removed if it has the
1044 specified value.</para></listitem>
1047 <term><command>default</command></term>
1049 <listitem><para>Enter default
1050 mode. This is mostly equivalent to
1052 default.target</command>.</para></listitem>
1055 <term><command>rescue</command></term>
1057 <listitem><para>Enter rescue
1058 mode. This is mostly equivalent to
1060 rescue.target</command> but also
1061 prints a wall message to all
1062 users.</para></listitem>
1065 <term><command>emergency</command></term>
1067 <listitem><para>Enter emergency
1068 mode. This is mostly equivalent to
1070 emergency.target</command> but also
1071 prints a wall message to all
1072 users.</para></listitem>
1075 <term><command>halt</command></term>
1077 <listitem><para>Shut down and halt the
1078 system. This is mostly equivalent to
1079 <command>start halt.target</command>
1080 but also prints a wall message to all
1081 users. If combined with
1082 <option>--force</option> shutdown of
1083 all running services is skipped,
1084 however all processes are killed and
1085 all file systems are unmounted or
1086 mounted read-only, immediately
1087 followed by the system halt. If
1088 <option>--force</option> is specified
1089 twice the the operation is immediately
1090 executed without terminating any
1091 processes or unmounting any file
1092 systems. This may result in data
1093 loss.</para></listitem>
1096 <term><command>poweroff</command></term>
1098 <listitem><para>Shut down and
1099 power-off the system. This is mostly
1100 equivalent to <command>start
1101 poweroff.target</command> but also
1102 prints a wall message to all users. If
1103 combined with <option>--force</option>
1104 shutdown of all running services is
1105 skipped, however all processes are
1106 killed and all file systems are
1107 unmounted or mounted read-only,
1108 immediately followed by the powering
1109 off. If <option>--force</option> is
1110 specified twice the the operation is
1111 immediately executed without
1112 terminating any processes or
1113 unmounting any file systems. This may
1114 result in data loss.</para></listitem>
1117 <term><command>reboot</command></term>
1119 <listitem><para>Shut down and reboot
1120 the system. This is mostly equivalent
1122 reboot.target</command> but also
1123 prints a wall message to all users. If
1124 combined with <option>--force</option>
1125 shutdown of all running services is
1126 skipped, however all processes are
1127 killed and all file systems are
1128 unmounted or mounted read-only,
1129 immediately followed by the reboot. If
1130 <option>--force</option> is specified
1131 twice the the operation is immediately
1132 executed without terminating any
1133 processes or unmounting any file
1134 systems. This may result in data
1135 loss.</para></listitem>
1138 <term><command>kexec</command></term>
1140 <listitem><para>Shut down and reboot
1141 the system via kexec. This is mostly
1142 equivalent to <command>start
1143 kexec.target</command> but also prints
1144 a wall message to all users. If
1145 combined with <option>--force</option>
1146 shutdown of all running services is
1147 skipped, however all processes are killed
1148 and all file systems are unmounted or
1149 mounted read-only, immediately
1151 reboot.</para></listitem>
1154 <term><command>exit</command></term>
1156 <listitem><para>Ask the systemd
1157 manager to quit. This is only
1158 supported for user service managers
1159 (i.e. in conjunction with the
1160 <option>--user</option> option) and
1161 will fail otherwise.</para></listitem>
1164 <term><command>suspend</command></term>
1166 <listitem><para>Suspend the system.</para></listitem>
1169 <term><command>hibernate</command></term>
1171 <listitem><para>Hibernate the system.</para></listitem>
1174 <term><command>switch-root [ROOT] [INIT]</command></term>
1176 <listitem><para>Switches to a
1177 different root directory and executes
1178 a new system manager process below
1179 it. This is intended for usage in
1180 initial RAM disks ("initrd"), and will
1181 transition from the initrd's system
1182 manager process (a.k.a "init" process)
1183 to the main system manager
1184 process. Takes two arguments: the
1185 directory to make the new root
1186 directory, and the path to the new
1187 system manager binary below it to
1188 execute as PID 1. If the latter is
1189 ommitted or the empty string, a
1190 systemd binary will automatically be
1191 searched for and used as init. If the
1192 system manager path is ommitted or
1193 equal the empty string the state of
1194 the initrd's system manager process is
1195 passed to the main system manager,
1196 which allows later introspection of the
1197 state of the services involved in the
1198 initrd boot.</para></listitem>
1205 <title>Exit status</title>
1207 <para>On success 0 is returned, a non-zero failure
1208 code otherwise.</para>
1212 <title>Environment</title>
1216 <term><varname>$SYSTEMD_PAGER</varname></term>
1217 <listitem><para>Pager to use when
1218 <option>--no-pager</option> is not given;
1219 overrides <varname>$PAGER</varname>. Setting
1220 this to an empty string or the value
1221 <literal>cat</literal> is equivalent to passing
1222 <option>--no-pager</option>.</para></listitem>
1228 <title>See Also</title>
1230 <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
1231 <citerefentry><refentrytitle>systemadm</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
1232 <citerefentry><refentrytitle>journalctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
1233 <citerefentry><refentrytitle>loginctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
1234 <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
1235 <citerefentry><refentrytitle>systemd.special</refentrytitle><manvolnum>7</manvolnum></citerefentry>,
1236 <citerefentry><refentrytitle>wall</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
1237 <citerefentry><refentrytitle>systemd.preset</refentrytitle><manvolnum>5</manvolnum></citerefentry>