1SYSTEMCTL(1) systemctl SYSTEMCTL(1)
2
3
4
6 systemctl - Control the systemd system and service manager
7
9 systemctl [OPTIONS...] COMMAND [UNIT...]
10
12 systemctl may be used to introspect and control the state of the
13 "systemd" system and service manager. Please refer to systemd(1) for an
14 introduction into the basic concepts and functionality this tool
15 manages.
16
18 The following commands are understood:
19
20 Unit Commands (Introspection and Modification)
21 list-units [PATTERN...]
22 List units that systemd currently has in memory. This includes
23 units that are either referenced directly or through a dependency,
24 units that are pinned by applications programmatically, or units
25 that were active in the past and have failed. By default only units
26 which are active, have pending jobs, or have failed are shown; this
27 can be changed with option --all. If one or more PATTERNs are
28 specified, only units matching one of them are shown. The units
29 that are shown are additionally filtered by --type= and --state= if
30 those options are specified.
31
32 Note that this command does not show unit templates, but only
33 instances of unit templates. Units templates that aren't
34 instantiated are not runnable, and will thus never show up in the
35 output of this command. Specifically this means that foo@.service
36 will never be shown in this list — unless instantiated, e.g. as
37 foo@bar.service. Use list-unit-files (see below) for listing
38 installed unit template files.
39
40 Produces output similar to
41
42 UNIT LOAD ACTIVE SUB DESCRIPTION
43 sys-module-fuse.device loaded active plugged /sys/module/fuse
44 -.mount loaded active mounted Root Mount
45 boot-efi.mount loaded active mounted /boot/efi
46 systemd-journald.service loaded active running Journal Service
47 systemd-logind.service loaded active running Login Service
48 ● user@1000.service loaded failed failed User Manager for UID 1000
49 ...
50 systemd-tmpfiles-clean.timer loaded active waiting Daily Cleanup of Temporary Directories
51
52 LOAD = Reflects whether the unit definition was properly loaded.
53 ACTIVE = The high-level unit activation state, i.e. generalization of SUB.
54 SUB = The low-level unit activation state, values depend on unit type.
55
56 123 loaded units listed. Pass --all to see loaded but inactive units, too.
57 To show all installed unit files use 'systemctl list-unit-files'.
58
59 The header and the last unit of a given type are underlined if the
60 terminal supports that. A colored dot is shown next to services
61 which were masked, not found, or otherwise failed.
62
63 The LOAD column shows the load state, one of loaded, not-found,
64 bad-setting, error, masked. The ACTIVE columns shows the general
65 unit state, one of active, reloading, inactive, failed, activating,
66 deactivating. The SUB column shows the unit-type-specific detailed
67 state of the unit, possible values vary by unit type. The list of
68 possible LOAD, ACTIVE, and SUB states is not constant and new
69 systemd releases may both add and remove values.
70
71 systemctl --state=help
72
73 command maybe be used to display the current set of possible
74 values.
75
76 This is the default command.
77
78 list-sockets [PATTERN...]
79 List socket units currently in memory, ordered by listening
80 address. If one or more PATTERNs are specified, only socket units
81 matching one of them are shown. Produces output similar to
82
83 LISTEN UNIT ACTIVATES
84 /dev/initctl systemd-initctl.socket systemd-initctl.service
85 ...
86 [::]:22 sshd.socket sshd.service
87 kobject-uevent 1 systemd-udevd-kernel.socket systemd-udevd.service
88
89 5 sockets listed.
90
91 Note: because the addresses might contains spaces, this output is
92 not suitable for programmatic consumption.
93
94 Also see --show-types, --all, and --state=.
95
96 list-timers [PATTERN...]
97 List timer units currently in memory, ordered by the time they
98 elapse next. If one or more PATTERNs are specified, only units
99 matching one of them are shown. Produces output similar to
100
101 NEXT LEFT LAST PASSED UNIT ACTIVATES
102 n/a n/a Thu 2017-02-23 13:40:29 EST 3 days ago ureadahead-stop.timer ureadahead-stop.service
103 Sun 2017-02-26 18:55:42 EST 1min 14s left Thu 2017-02-23 13:54:44 EST 3 days ago systemd-tmpfiles-clean.timer systemd-tmpfiles-clean.service
104 Sun 2017-02-26 20:37:16 EST 1h 42min left Sun 2017-02-26 11:56:36 EST 6h ago apt-daily.timer apt-daily.service
105 Sun 2017-02-26 20:57:49 EST 2h 3min left Sun 2017-02-26 11:56:36 EST 6h ago snapd.refresh.timer snapd.refresh.service
106
107
108 NEXT shows the next time the timer will run.
109
110 LEFT shows how long till the next time the timer runs.
111
112 LAST shows the last time the timer ran.
113
114 PASSED shows how long has passed since the timer last ran.
115
116 UNIT shows the name of the timer
117
118 ACTIVATES shows the name the service the timer activates when it
119 runs.
120
121 Also see --all and --state=.
122
123 is-active PATTERN...
124 Check whether any of the specified units are active (i.e. running).
125 Returns an exit code 0 if at least one is active, or non-zero
126 otherwise. Unless --quiet is specified, this will also print the
127 current unit state to standard output.
128
129 is-failed PATTERN...
130 Check whether any of the specified units are in a "failed" state.
131 Returns an exit code 0 if at least one has failed, non-zero
132 otherwise. Unless --quiet is specified, this will also print the
133 current unit state to standard output.
134
135 status [PATTERN...|PID...]]
136 Show terse runtime status information about one or more units,
137 followed by most recent log data from the journal. If no units are
138 specified, show system status. If combined with --all, also show
139 the status of all units (subject to limitations specified with -t).
140 If a PID is passed, show information about the unit the process
141 belongs to.
142
143 This function is intended to generate human-readable output. If you
144 are looking for computer-parsable output, use show instead. By
145 default, this function only shows 10 lines of output and ellipsizes
146 lines to fit in the terminal window. This can be changed with
147 --lines and --full, see above. In addition, journalctl --unit=NAME
148 or journalctl --user-unit=NAME use a similar filter for messages
149 and might be more convenient.
150
151 systemd implicitly loads units as necessary, so just running the
152 status will attempt to load a file. The command is thus not useful
153 for determining if something was already loaded or not. The units
154 may possibly also be quickly unloaded after the operation is
155 completed if there's no reason to keep it in memory thereafter.
156
157 Example 1. Example output from systemctl status
158
159 $ systemctl status bluetooth
160 ● bluetooth.service - Bluetooth service
161 Loaded: loaded (/usr/lib/systemd/system/bluetooth.service; enabled; vendor preset: enabled)
162 Active: active (running) since Wed 2017-01-04 13:54:04 EST; 1 weeks 0 days ago
163 Docs: man:bluetoothd(8)
164 Main PID: 930 (bluetoothd)
165 Status: "Running"
166 Tasks: 1
167 Memory: 648.0K
168 CPU: 435ms
169 CGroup: /system.slice/bluetooth.service
170 └─930 /usr/lib/bluetooth/bluetoothd
171
172 Jan 12 10:46:45 example.com bluetoothd[8900]: Not enough free handles to register service
173 Jan 12 10:46:45 example.com bluetoothd[8900]: Current Time Service could not be registered
174 Jan 12 10:46:45 example.com bluetoothd[8900]: gatt-time-server: Input/output error (5)
175
176 The dot ("●") uses color on supported terminals to summarize the
177 unit state at a glance. Along with its color, its shape varies
178 according to its state: "inactive" or "maintenance" is a white
179 circle ("○"), "active" is a green dot ("●"), "deactivating" is a
180 white dot, "failed" or "error" is a red cross ("×"), and
181 "reloading" is a green clockwise circle arrow ("↻").
182
183 The "Loaded:" line in the output will show "loaded" if the unit has
184 been loaded into memory. Other possible values for "Loaded:"
185 include: "error" if there was a problem loading it, "not-found" if
186 no unit file was found for this unit, "bad-setting" if an essential
187 unit file setting could not be parsed and "masked" if the unit file
188 has been masked. Along with showing the path to the unit file, this
189 line will also show the enablement state. Enabled units are
190 included in the dependency network between units, and thus are
191 started at boot or via some other form of activation. See the full
192 table of possible enablement states — including the definition of
193 "masked" — in the documentation for the is-enabled command.
194
195 The "Active:" line shows active state. The value is usually
196 "active" or "inactive". Active could mean started, bound, plugged
197 in, etc depending on the unit type. The unit could also be in
198 process of changing states, reporting a state of "activating" or
199 "deactivating". A special "failed" state is entered when the
200 service failed in some way, such as a crash, exiting with an error
201 code or timing out. If the failed state is entered the cause will
202 be logged for later reference.
203
204 show [PATTERN...|JOB...]
205 Show properties of one or more units, jobs, or the manager itself.
206 If no argument is specified, properties of the manager will be
207 shown. If a unit name is specified, properties of the unit are
208 shown, and if a job ID is specified, properties of the job are
209 shown. By default, empty properties are suppressed. Use --all to
210 show those too. To select specific properties to show, use
211 --property=. This command is intended to be used whenever
212 computer-parsable output is required. Use status if you are looking
213 for formatted human-readable output.
214
215 Many properties shown by systemctl show map directly to
216 configuration settings of the system and service manager and its
217 unit files. Note that the properties shown by the command are
218 generally more low-level, normalized versions of the original
219 configuration settings and expose runtime state in addition to
220 configuration. For example, properties shown for service units
221 include the service's current main process identifier as "MainPID"
222 (which is runtime state), and time settings are always exposed as
223 properties ending in the "...USec" suffix even if a matching
224 configuration options end in "...Sec", because microseconds is the
225 normalized time unit used internally by the system and service
226 manager.
227
228 For details about many of these properties, see the documentation
229 of the D-Bus interface backing these properties, see
230 org.freedesktop.systemd1(5).
231
232 cat PATTERN...
233 Show backing files of one or more units. Prints the "fragment" and
234 "drop-ins" (source files) of units. Each file is preceded by a
235 comment which includes the file name. Note that this shows the
236 contents of the backing files on disk, which may not match the
237 system manager's understanding of these units if any unit files
238 were updated on disk and the daemon-reload command wasn't issued
239 since.
240
241 help PATTERN...|PID...
242 Show manual pages for one or more units, if available. If a PID is
243 given, the manual pages for the unit the process belongs to are
244 shown.
245
246 list-dependencies [UNIT...]
247 Shows units required and wanted by the specified units. This
248 recursively lists units following the Requires=, Requisite=,
249 ConsistsOf=, Wants=, BindsTo= dependencies. If no units are
250 specified, default.target is implied.
251
252 By default, only target units are recursively expanded. When --all
253 is passed, all other units are recursively expanded as well.
254
255 Options --reverse, --after, --before may be used to change what
256 types of dependencies are shown.
257
258 Note that this command only lists units currently loaded into
259 memory by the service manager. In particular, this command is not
260 suitable to get a comprehensive list at all reverse dependencies on
261 a specific unit, as it won't list the dependencies declared by
262 units currently not loaded.
263
264 start PATTERN...
265 Start (activate) one or more units specified on the command line.
266
267 Note that unit glob patterns expand to names of units currently in
268 memory. Units which are not active and are not in a failed state
269 usually are not in memory, and will not be matched by any pattern.
270 In addition, in case of instantiated units, systemd is often
271 unaware of the instance name until the instance has been started.
272 Therefore, using glob patterns with start has limited usefulness.
273 Also, secondary alias names of units are not considered.
274
275 Option --all may be used to also operate on inactive units which
276 are referenced by other loaded units. Note that this is not the
277 same as operating on "all" possible units, because as the previous
278 paragraph describes, such a list is ill-defined. Nevertheless,
279 systemctl start --all GLOB may be useful if all the units that
280 should match the pattern are pulled in by some target which is
281 known to be loaded.
282
283 stop PATTERN...
284 Stop (deactivate) one or more units specified on the command line.
285
286 This command will fail if the unit does not exist or if stopping of
287 the unit is prohibited (see RefuseManualStop= in systemd.unit(5)).
288 It will not fail if any of the commands configured to stop the unit
289 (ExecStop=, etc.) fail, because the manager will still forcibly
290 terminate the unit.
291
292 reload PATTERN...
293 Asks all units listed on the command line to reload their
294 configuration. Note that this will reload the service-specific
295 configuration, not the unit configuration file of systemd. If you
296 want systemd to reload the configuration file of a unit, use the
297 daemon-reload command. In other words: for the example case of
298 Apache, this will reload Apache's httpd.conf in the web server, not
299 the apache.service systemd unit file.
300
301 This command should not be confused with the daemon-reload command.
302
303 restart PATTERN...
304 Stop and then start one or more units specified on the command
305 line. If the units are not running yet, they will be started.
306
307 Note that restarting a unit with this command does not necessarily
308 flush out all of the unit's resources before it is started again.
309 For example, the per-service file descriptor storage facility (see
310 FileDescriptorStoreMax= in systemd.service(5)) will remain intact
311 as long as the unit has a job pending, and is only cleared when the
312 unit is fully stopped and no jobs are pending anymore. If it is
313 intended that the file descriptor store is flushed out, too, during
314 a restart operation an explicit systemctl stop command followed by
315 systemctl start should be issued.
316
317 try-restart PATTERN...
318 Stop and then start one or more units specified on the command line
319 if the units are running. This does nothing if units are not
320 running.
321
322 reload-or-restart PATTERN...
323 Reload one or more units if they support it. If not, stop and then
324 start them instead. If the units are not running yet, they will be
325 started.
326
327 try-reload-or-restart PATTERN...
328 Reload one or more units if they support it. If not, stop and then
329 start them instead. This does nothing if the units are not running.
330
331 isolate UNIT
332 Start the unit specified on the command line and its dependencies
333 and stop all others, unless they have IgnoreOnIsolate=yes (see
334 systemd.unit(5)). If a unit name with no extension is given, an
335 extension of ".target" will be assumed.
336
337 This command is dangerous, since it will immediately stop processes
338 that are not enabled in the new target, possibly including the
339 graphical environment or terminal you are currently using.
340
341 Note that this is allowed only on units where AllowIsolate= is
342 enabled. See systemd.unit(5) for details.
343
344 kill PATTERN...
345 Send a signal to one or more processes of the unit. Use --kill-who=
346 to select which process to kill. Use --signal= to select the signal
347 to send.
348
349 clean PATTERN...
350 Remove the configuration, state, cache, logs or runtime data of the
351 specified units. Use --what= to select which kind of resource to
352 remove. For service units this may be used to remove the
353 directories configured with ConfigurationDirectory=,
354 StateDirectory=, CacheDirectory=, LogsDirectory= and
355 RuntimeDirectory=, see systemd.exec(5) for details. For timer units
356 this may be used to clear out the persistent timestamp data if
357 Persistent= is used and --what=state is selected, see
358 systemd.timer(5). This command only applies to units that use
359 either of these settings. If --what= is not specified, both the
360 cache and runtime data are removed (as these two types of data are
361 generally redundant and reproducible on the next invocation of the
362 unit).
363
364 freeze PATTERN...
365 Freeze one or more units specified on the command line using cgroup
366 freezer
367
368 Freezing the unit will cause all processes contained within the
369 cgroup corresponding to the unit to be suspended. Being suspended
370 means that unit's processes won't be scheduled to run on CPU until
371 thawed. Note that this command is supported only on systems that
372 use unified cgroup hierarchy. Unit is automatically thawed just
373 before we execute a job against the unit, e.g. before the unit is
374 stopped.
375
376 thaw PATTERN...
377 Thaw (unfreeze) one or more units specified on the command line.
378
379 This is the inverse operation to the freeze command and resumes the
380 execution of processes in the unit's cgroup.
381
382 set-property UNIT PROPERTY=VALUE...
383 Set the specified unit properties at runtime where this is
384 supported. This allows changing configuration parameter properties
385 such as resource control settings at runtime. Not all properties
386 may be changed at runtime, but many resource control settings
387 (primarily those in systemd.resource-control(5)) may. The changes
388 are applied immediately, and stored on disk for future boots,
389 unless --runtime is passed, in which case the settings only apply
390 until the next reboot. The syntax of the property assignment
391 follows closely the syntax of assignments in unit files.
392
393 Example: systemctl set-property foobar.service CPUWeight=200
394
395 If the specified unit appears to be inactive, the changes will be
396 only stored on disk as described previously hence they will be
397 effective when the unit will be started.
398
399 Note that this command allows changing multiple properties at the
400 same time, which is preferable over setting them individually.
401
402 Example: systemctl set-property foobar.service CPUWeight=200
403 MemoryMax=2G IPAccounting=yes
404
405 Like with unit file configuration settings, assigning an empty
406 setting usually resets a property to its defaults.
407
408 Example: systemctl set-property avahi-daemon.service IPAddressDeny=
409
410 bind UNIT PATH [PATH]
411 Bind-mounts a file or directory from the host into the specified
412 unit's mount namespace. The first path argument is the source file
413 or directory on the host, the second path argument is the
414 destination file or directory in the unit's mount namespace. When
415 the latter is omitted, the destination path in the unit's mount
416 namespace is the same as the source path on the host. When combined
417 with the --read-only switch, a ready-only bind mount is created.
418 When combined with the --mkdir switch, the destination path is
419 first created before the mount is applied.
420
421 Note that this option is currently only supported for units that
422 run within a mount namespace (e.g.: with RootImage=,
423 PrivateMounts=, etc.). This command supports bind-mounting
424 directories, regular files, device nodes, AF_UNIX socket nodes, as
425 well as FIFOs. The bind mount is ephemeral, and it is undone as
426 soon as the current unit process exists. Note that the namespace
427 mentioned here, where the bind mount will be added to, is the one
428 where the main service process runs. Other processes (those
429 exececuted by ExecReload=, ExecStartPre=, etc.) run in distinct
430 namespaces.
431
432 mount-image UNIT IMAGE [PATH [PARTITION_NAME:MOUNT_OPTIONS]]
433 Mounts an image from the host into the specified unit's mount
434 namespace. The first path argument is the source image on the host,
435 the second path argument is the destination directory in the unit's
436 mount namespace (i.e. inside RootImage=/RootDirectory=). The
437 following argument, if any, is interpreted as a colon-separated
438 tuple of partition name and comma-separated list of mount options
439 for that partition. The format is the same as the service
440 MountImages= setting. When combined with the --read-only switch, a
441 ready-only mount is created. When combined with the --mkdir switch,
442 the destination path is first created before the mount is applied.
443
444 Note that this option is currently only supported for units that
445 run within a mount namespace (i.e. with RootImage=, PrivateMounts=,
446 etc.). Note that the namespace mentioned here where the image mount
447 will be added to, is the one where the main service process runs.
448 Note that the namespace mentioned here, where the bind mount will
449 be added to, is the one where the main service process runs. Other
450 processes (those exececuted by ExecReload=, ExecStartPre=, etc.)
451 run in distinct namespaces.
452
453 Example:
454
455 systemctl mount-image foo.service /tmp/img.raw /var/lib/image root:ro,nosuid
456
457
458
459 systemctl mount-image --mkdir bar.service /tmp/img.raw /var/lib/baz/img
460
461
462 service-log-level SERVICE [LEVEL]
463 If the LEVEL argument is not given, print the current log level as
464 reported by service SERVICE.
465
466 If the optional argument LEVEL is provided, then change the current
467 log level of the service to LEVEL. The log level should be a
468 typical syslog log level, i.e. a value in the range 0...7 or one of
469 the strings emerg, alert, crit, err, warning, notice, info, debug;
470 see syslog(3) for details.
471
472 The service must have the appropriate BusName=destination property
473 and also implement the generic org.freedesktop.LogControl1(5)
474 interface. (systemctl will use the generic D-Bus protocol to access
475 the org.freedesktop.LogControl1.LogLevel interface for the D-Bus
476 name destination.)
477
478 service-log-target SERVICE [TARGET]
479 If the TARGET argument is not given, print the current log target
480 as reported by service SERVICE.
481
482 If the optional argument TARGET is provided, then change the
483 current log target of the service to TARGET. The log target should
484 be one of the strings console (for log output to the service's
485 standard error stream), kmsg (for log output to the kernel log
486 buffer), journal (for log output to systemd-journald.service(8)
487 using the native journal protocol), syslog (for log output to the
488 classic syslog socket /dev/log), null (for no log output
489 whatsoever) or auto (for an automatically determined choice,
490 typically equivalent to console if the service is invoked
491 interactively, and journal or syslog otherwise).
492
493 For most services, only a small subset of log targets make sense.
494 In particular, most "normal" services should only implement
495 console, journal, and null. Anything else is only appropriate for
496 low-level services that are active in very early boot before proper
497 logging is established.
498
499 The service must have the appropriate BusName=destination property
500 and also implement the generic org.freedesktop.LogControl1(5)
501 interface. (systemctl will use the generic D-Bus protocol to access
502 the org.freedesktop.LogControl1.LogLevel interface for the D-Bus
503 name destination.)
504
505 reset-failed [PATTERN...]
506 Reset the "failed" state of the specified units, or if no unit name
507 is passed, reset the state of all units. When a unit fails in some
508 way (i.e. process exiting with non-zero error code, terminating
509 abnormally or timing out), it will automatically enter the "failed"
510 state and its exit code and status is recorded for introspection by
511 the administrator until the service is stopped/re-started or reset
512 with this command.
513
514 In addition to resetting the "failed" state of a unit it also
515 resets various other per-unit properties: the start rate limit
516 counter of all unit types is reset to zero, as is the restart
517 counter of service units. Thus, if a unit's start limit (as
518 configured with StartLimitIntervalSec=/StartLimitBurst=) is hit and
519 the unit refuses to be started again, use this command to make it
520 startable again.
521
522 Unit File Commands
523 list-unit-files [PATTERN...]
524 List unit files installed on the system, in combination with their
525 enablement state (as reported by is-enabled). If one or more
526 PATTERNs are specified, only unit files whose name matches one of
527 them are shown (patterns matching unit file system paths are not
528 supported).
529
530 Unlike list-units this command will list template units in addition
531 to explicitly instantiated units.
532
533 enable UNIT..., enable PATH...
534 Enable one or more units or unit instances. This will create a set
535 of symlinks, as encoded in the [Install] sections of the indicated
536 unit files. After the symlinks have been created, the system
537 manager configuration is reloaded (in a way equivalent to
538 daemon-reload), in order to ensure the changes are taken into
539 account immediately. Note that this does not have the effect of
540 also starting any of the units being enabled. If this is desired,
541 combine this command with the --now switch, or invoke start with
542 appropriate arguments later. Note that in case of unit instance
543 enablement (i.e. enablement of units of the form foo@bar.service),
544 symlinks named the same as instances are created in the unit
545 configuration directory, however they point to the single template
546 unit file they are instantiated from.
547
548 This command expects either valid unit names (in which case various
549 unit file directories are automatically searched for unit files
550 with appropriate names), or absolute paths to unit files (in which
551 case these files are read directly). If a specified unit file is
552 located outside of the usual unit file directories, an additional
553 symlink is created, linking it into the unit configuration path,
554 thus ensuring it is found when requested by commands such as start.
555 The file system where the linked unit files are located must be
556 accessible when systemd is started (e.g. anything underneath /home/
557 or /var/ is not allowed, unless those directories are located on
558 the root file system).
559
560 This command will print the file system operations executed. This
561 output may be suppressed by passing --quiet.
562
563 Note that this operation creates only the symlinks suggested in the
564 [Install] section of the unit files. While this command is the
565 recommended way to manipulate the unit configuration directory, the
566 administrator is free to make additional changes manually by
567 placing or removing symlinks below this directory. This is
568 particularly useful to create configurations that deviate from the
569 suggested default installation. In this case, the administrator
570 must make sure to invoke daemon-reload manually as necessary, in
571 order to ensure the changes are taken into account.
572
573 Enabling units should not be confused with starting (activating)
574 units, as done by the start command. Enabling and starting units is
575 orthogonal: units may be enabled without being started and started
576 without being enabled. Enabling simply hooks the unit into various
577 suggested places (for example, so that the unit is automatically
578 started on boot or when a particular kind of hardware is plugged
579 in). Starting actually spawns the daemon process (in case of
580 service units), or binds the socket (in case of socket units), and
581 so on.
582
583 Depending on whether --system, --user, --runtime, or --global is
584 specified, this enables the unit for the system, for the calling
585 user only, for only this boot of the system, or for all future
586 logins of all users. Note that in the last case, no systemd daemon
587 configuration is reloaded.
588
589 Using enable on masked units is not supported and results in an
590 error.
591
592 disable UNIT...
593 Disables one or more units. This removes all symlinks to the unit
594 files backing the specified units from the unit configuration
595 directory, and hence undoes any changes made by enable or link.
596 Note that this removes all symlinks to matching unit files,
597 including manually created symlinks, and not just those actually
598 created by enable or link. Note that while disable undoes the
599 effect of enable, the two commands are otherwise not symmetric, as
600 disable may remove more symlinks than a prior enable invocation of
601 the same unit created.
602
603 This command expects valid unit names only, it does not accept
604 paths to unit files.
605
606 In addition to the units specified as arguments, all units are
607 disabled that are listed in the Also= setting contained in the
608 [Install] section of any of the unit files being operated on.
609
610 This command implicitly reloads the system manager configuration
611 after completing the operation. Note that this command does not
612 implicitly stop the units that are being disabled. If this is
613 desired, either combine this command with the --now switch, or
614 invoke the stop command with appropriate arguments later.
615
616 This command will print information about the file system
617 operations (symlink removals) executed. This output may be
618 suppressed by passing --quiet.
619
620 This command honors --system, --user, --runtime and --global in a
621 similar way as enable.
622
623 reenable UNIT...
624 Reenable one or more units, as specified on the command line. This
625 is a combination of disable and enable and is useful to reset the
626 symlinks a unit file is enabled with to the defaults configured in
627 its [Install] section. This command expects a unit name only, it
628 does not accept paths to unit files.
629
630 preset UNIT...
631 Reset the enable/disable status one or more unit files, as
632 specified on the command line, to the defaults configured in the
633 preset policy files. This has the same effect as disable or enable,
634 depending how the unit is listed in the preset files.
635
636 Use --preset-mode= to control whether units shall be enabled and
637 disabled, or only enabled, or only disabled.
638
639 If the unit carries no install information, it will be silently
640 ignored by this command. UNIT must be the real unit name, any
641 alias names are ignored silently.
642
643 For more information on the preset policy format, see
644 systemd.preset(5).
645
646 preset-all
647 Resets all installed unit files to the defaults configured in the
648 preset policy file (see above).
649
650 Use --preset-mode= to control whether units shall be enabled and
651 disabled, or only enabled, or only disabled.
652
653 is-enabled UNIT...
654 Checks whether any of the specified unit files are enabled (as with
655 enable). Returns an exit code of 0 if at least one is enabled,
656 non-zero otherwise. Prints the current enable status (see table).
657 To suppress this output, use --quiet. To show installation targets,
658 use --full.
659
660 Table 1. is-enabled output
661 ┌──────────────────┬─────────────────────────┬───────────┐
662 │Name │ Description │ Exit Code │
663 ├──────────────────┼─────────────────────────┼───────────┤
664 │"enabled" │ Enabled via │ │
665 ├──────────────────┤ .wants/, .requires/ │ │
666 │"enabled-runtime" │ or Alias= symlinks │ │
667 │ │ (permanently in │ 0 │
668 │ │ /etc/systemd/system/, │ │
669 │ │ or transiently in │ │
670 │ │ /run/systemd/system/). │ │
671 ├──────────────────┼─────────────────────────┼───────────┤
672 │"linked" │ Made available through │ │
673 ├──────────────────┤ one or more symlinks │ │
674 │"linked-runtime" │ to the unit file │ │
675 │ │ (permanently in │ │
676 │ │ /etc/systemd/system/ │ │
677 │ │ or transiently in │ > 0 │
678 │ │ /run/systemd/system/), │ │
679 │ │ even though the unit │ │
680 │ │ file might reside │ │
681 │ │ outside of the unit │ │
682 │ │ file search path. │ │
683 ├──────────────────┼─────────────────────────┼───────────┤
684 │"alias" │ The name is an alias │ 0 │
685 │ │ (symlink to another │ │
686 │ │ unit file). │ │
687 ├──────────────────┼─────────────────────────┼───────────┤
688 │"masked" │ Completely disabled, │ │
689 ├──────────────────┤ so that any start │ │
690 │"masked-runtime" │ operation on it fails │ │
691 │ │ (permanently in │ > 0 │
692 │ │ /etc/systemd/system/ │ │
693 │ │ or transiently in │ │
694 │ │ /run/systemd/systemd/). │ │
695 ├──────────────────┼─────────────────────────┼───────────┤
696 │"static" │ The unit file is not │ 0 │
697 │ │ enabled, and has no │ │
698 │ │ provisions for enabling │ │
699 │ │ in the [Install] unit │ │
700 │ │ file section. │ │
701 ├──────────────────┼─────────────────────────┼───────────┤
702 │"indirect" │ The unit file itself is │ 0 │
703 │ │ not enabled, but it has │ │
704 │ │ a non-empty Also= │ │
705 │ │ setting in the │ │
706 │ │ [Install] unit file │ │
707 │ │ section, listing other │ │
708 │ │ unit files that might │ │
709 │ │ be enabled, or it has │ │
710 │ │ an alias under a │ │
711 │ │ different name through │ │
712 │ │ a symlink that is not │ │
713 │ │ specified in Also=. For │ │
714 │ │ template unit files, an │ │
715 │ │ instance different than │ │
716 │ │ the one specified in │ │
717 │ │ DefaultInstance= is │ │
718 │ │ enabled. │ │
719 ├──────────────────┼─────────────────────────┼───────────┤
720 │"disabled" │ The unit file is not │ > 0 │
721 │ │ enabled, but contains │ │
722 │ │ an [Install] section │ │
723 │ │ with installation │ │
724 │ │ instructions. │ │
725 ├──────────────────┼─────────────────────────┼───────────┤
726 │"generated" │ The unit file was │ 0 │
727 │ │ generated dynamically │ │
728 │ │ via a generator tool. │ │
729 │ │ See │ │
730 │ │ systemd.generator(7). │ │
731 │ │ Generated unit files │ │
732 │ │ may not be enabled, │ │
733 │ │ they are enabled │ │
734 │ │ implicitly by their │ │
735 │ │ generator. │ │
736 ├──────────────────┼─────────────────────────┼───────────┤
737 │"transient" │ The unit file has been │ 0 │
738 │ │ created dynamically │ │
739 │ │ with the runtime API. │ │
740 │ │ Transient units may not │ │
741 │ │ be enabled. │ │
742 ├──────────────────┼─────────────────────────┼───────────┤
743 │"bad" │ The unit file is │ > 0 │
744 │ │ invalid or another │ │
745 │ │ error occurred. Note │ │
746 │ │ that is-enabled will │ │
747 │ │ not actually return │ │
748 │ │ this state, but print │ │
749 │ │ an error message │ │
750 │ │ instead. However the │ │
751 │ │ unit file listing │ │
752 │ │ printed by │ │
753 │ │ list-unit-files might │ │
754 │ │ show it. │ │
755 └──────────────────┴─────────────────────────┴───────────┘
756
757 mask UNIT...
758 Mask one or more units, as specified on the command line. This will
759 link these unit files to /dev/null, making it impossible to start
760 them. This is a stronger version of disable, since it prohibits all
761 kinds of activation of the unit, including enablement and manual
762 activation. Use this option with care. This honors the --runtime
763 option to only mask temporarily until the next reboot of the
764 system. The --now option may be used to ensure that the units are
765 also stopped. This command expects valid unit names only, it does
766 not accept unit file paths.
767
768 unmask UNIT...
769 Unmask one or more unit files, as specified on the command line.
770 This will undo the effect of mask. This command expects valid unit
771 names only, it does not accept unit file paths.
772
773 link PATH...
774 Link a unit file that is not in the unit file search paths into the
775 unit file search path. This command expects an absolute path to a
776 unit file. The effect of this may be undone with disable. The
777 effect of this command is that a unit file is made available for
778 commands such as start, even though it is not installed directly in
779 the unit search path. The file system where the linked unit files
780 are located must be accessible when systemd is started (e.g.
781 anything underneath /home/ or /var/ is not allowed, unless those
782 directories are located on the root file system).
783
784 revert UNIT...
785 Revert one or more unit files to their vendor versions. This
786 command removes drop-in configuration files that modify the
787 specified units, as well as any user-configured unit file that
788 overrides a matching vendor supplied unit file. Specifically, for a
789 unit "foo.service" the matching directories "foo.service.d/" with
790 all their contained files are removed, both below the persistent
791 and runtime configuration directories (i.e. below
792 /etc/systemd/system and /run/systemd/system); if the unit file has
793 a vendor-supplied version (i.e. a unit file located below /usr/)
794 any matching persistent or runtime unit file that overrides it is
795 removed, too. Note that if a unit file has no vendor-supplied
796 version (i.e. is only defined below /etc/systemd/system or
797 /run/systemd/system, but not in a unit file stored below /usr/),
798 then it is not removed. Also, if a unit is masked, it is unmasked.
799
800 Effectively, this command may be used to undo all changes made with
801 systemctl edit, systemctl set-property and systemctl mask and puts
802 the original unit file with its settings back in effect.
803
804 add-wants TARGET UNIT..., add-requires TARGET UNIT...
805 Adds "Wants=" or "Requires=" dependencies, respectively, to the
806 specified TARGET for one or more units.
807
808 This command honors --system, --user, --runtime and --global in a
809 way similar to enable.
810
811 edit UNIT...
812 Edit a drop-in snippet or a whole replacement file if --full is
813 specified, to extend or override the specified unit.
814
815 Depending on whether --system (the default), --user, or --global is
816 specified, this command creates a drop-in file for each unit either
817 for the system, for the calling user, or for all futures logins of
818 all users. Then, the editor (see the "Environment" section below)
819 is invoked on temporary files which will be written to the real
820 location if the editor exits successfully.
821
822 If --full is specified, this will copy the original units instead
823 of creating drop-in files.
824
825 If --force is specified and any units do not already exist, new
826 unit files will be opened for editing.
827
828 If --runtime is specified, the changes will be made temporarily in
829 /run/ and they will be lost on the next reboot.
830
831 If the temporary file is empty upon exit, the modification of the
832 related unit is canceled.
833
834 After the units have been edited, systemd configuration is reloaded
835 (in a way that is equivalent to daemon-reload).
836
837 Note that this command cannot be used to remotely edit units and
838 that you cannot temporarily edit units which are in /etc/, since
839 they take precedence over /run/.
840
841 get-default
842 Return the default target to boot into. This returns the target
843 unit name default.target is aliased (symlinked) to.
844
845 set-default TARGET
846 Set the default target to boot into. This sets (symlinks) the
847 default.target alias to the given target unit.
848
849 Machine Commands
850 list-machines [PATTERN...]
851 List the host and all running local containers with their state. If
852 one or more PATTERNs are specified, only containers matching one of
853 them are shown.
854
855 Job Commands
856 list-jobs [PATTERN...]
857 List jobs that are in progress. If one or more PATTERNs are
858 specified, only jobs for units matching one of them are shown.
859
860 When combined with --after or --before the list is augmented with
861 information on which other job each job is waiting for, and which
862 other jobs are waiting for it, see above.
863
864 cancel JOB...
865 Cancel one or more jobs specified on the command line by their
866 numeric job IDs. If no job ID is specified, cancel all pending
867 jobs.
868
869 Environment Commands
870 systemd supports an environment block that is passed to processes the
871 manager spawns. The names of the variables can contain ASCII letters,
872 digits, and the underscore character. Variable names cannot be empty or
873 start with a digit. In variable values, most characters are allowed,
874 but the whole sequence must be valid UTF-8. (Note that control
875 characters like newline (NL), tab (TAB), or the escape character (ESC),
876 are valid ASCII and thus valid UTF-8). The total length of the
877 environment block is limited to _SC_ARG_MAX value defined by
878 sysconf(3).
879
880 show-environment
881 Dump the systemd manager environment block. This is the environment
882 block that is passed to all processes the manager spawns. The
883 environment block will be dumped in straight-forward form suitable
884 for sourcing into most shells. If no special characters or
885 whitespace is present in the variable values, no escaping is
886 performed, and the assignments have the form "VARIABLE=value". If
887 whitespace or characters which have special meaning to the shell
888 are present, dollar-single-quote escaping is used, and assignments
889 have the form "VARIABLE=$'value'". This syntax is known to be
890 supported by bash(1), zsh(1), ksh(1), and busybox(1)'s ash(1), but
891 not dash(1) or fish(1).
892
893 set-environment VARIABLE=VALUE...
894 Set one or more systemd manager environment variables, as specified
895 on the command line. This command will fail if variable names and
896 values do not conform to the rules listed above.
897
898 unset-environment VARIABLE...
899 Unset one or more systemd manager environment variables. If only a
900 variable name is specified, it will be removed regardless of its
901 value. If a variable and a value are specified, the variable is
902 only removed if it has the specified value.
903
904 import-environment VARIABLE...
905 Import all, one or more environment variables set on the client
906 into the systemd manager environment block. If a list of
907 environment variable names is passed, client-side values are then
908 imported into the manager's environment block. If any names are not
909 valid environment variable names or have invalid values according
910 to the rules described above, an error is raised. If no arguments
911 are passed, the entire environment block inherited by the systemctl
912 process is imported. In this mode, any inherited invalid
913 environment variables are quietly ignored.
914
915 Importing of the full inherited environment block (calling this
916 command without any arguments) is deprecated. A shell will set
917 dozens of variables which only make sense locally and are only
918 meant for processes which are descendants of the shell. Such
919 variables in the global environment block are confusing to other
920 processes.
921
922 Manager State Commands
923 daemon-reload
924 Reload the systemd manager configuration. This will rerun all
925 generators (see systemd.generator(7)), reload all unit files, and
926 recreate the entire dependency tree. While the daemon is being
927 reloaded, all sockets systemd listens on behalf of user
928 configuration will stay accessible.
929
930 This command should not be confused with the reload command.
931
932 daemon-reexec
933 Reexecute the systemd manager. This will serialize the manager
934 state, reexecute the process and deserialize the state again. This
935 command is of little use except for debugging and package upgrades.
936 Sometimes, it might be helpful as a heavy-weight daemon-reload.
937 While the daemon is being reexecuted, all sockets systemd listening
938 on behalf of user configuration will stay accessible.
939
940 log-level [LEVEL]
941 If no argument is given, print the current log level of the
942 manager. If an optional argument LEVEL is provided, then the
943 command changes the current log level of the manager to LEVEL
944 (accepts the same values as --log-level= described in systemd(1)).
945
946 log-target [TARGET]
947 If no argument is given, print the current log target of the
948 manager. If an optional argument TARGET is provided, then the
949 command changes the current log target of the manager to TARGET
950 (accepts the same values as --log-target=, described in
951 systemd(1)).
952
953 service-watchdogs [yes|no]
954 If no argument is given, print the current state of service runtime
955 watchdogs of the manager. If an optional boolean argument is
956 provided, then globally enables or disables the service runtime
957 watchdogs (WatchdogSec=) and emergency actions (e.g. OnFailure= or
958 StartLimitAction=); see systemd.service(5). The hardware watchdog
959 is not affected by this setting.
960
961 System Commands
962 is-system-running
963 Checks whether the system is operational. This returns success
964 (exit code 0) when the system is fully up and running, specifically
965 not in startup, shutdown or maintenance mode, and with no failed
966 services. Failure is returned otherwise (exit code non-zero). In
967 addition, the current state is printed in a short string to
968 standard output, see the table below. Use --quiet to suppress this
969 output.
970
971 Use --wait to wait until the boot process is completed before
972 printing the current state and returning the appropriate error
973 status. If --wait is in use, states initializing or starting will
974 not be reported, instead the command will block until a later state
975 (such as running or degraded) is reached.
976
977 Table 2. is-system-running output
978 ┌─────────────┬─────────────────────┬───────────┐
979 │Name │ Description │ Exit Code │
980 ├─────────────┼─────────────────────┼───────────┤
981 │initializing │ Early bootup, │ > 0 │
982 │ │ before basic.target │ │
983 │ │ is reached or the │ │
984 │ │ maintenance state │ │
985 │ │ entered. │ │
986 ├─────────────┼─────────────────────┼───────────┤
987 │starting │ Late bootup, before │ > 0 │
988 │ │ the job queue │ │
989 │ │ becomes idle for │ │
990 │ │ the first time, or │ │
991 │ │ one of the rescue │ │
992 │ │ targets are │ │
993 │ │ reached. │ │
994 ├─────────────┼─────────────────────┼───────────┤
995 │running │ The system is fully │ 0 │
996 │ │ operational. │ │
997 ├─────────────┼─────────────────────┼───────────┤
998 │degraded │ The system is │ > 0 │
999 │ │ operational but one │ │
1000 │ │ or more units │ │
1001 │ │ failed. │ │
1002 ├─────────────┼─────────────────────┼───────────┤
1003 │maintenance │ The rescue or │ > 0 │
1004 │ │ emergency target is │ │
1005 │ │ active. │ │
1006 ├─────────────┼─────────────────────┼───────────┤
1007 │stopping │ The manager is │ > 0 │
1008 │ │ shutting down. │ │
1009 ├─────────────┼─────────────────────┼───────────┤
1010 │offline │ The manager is not │ > 0 │
1011 │ │ running. │ │
1012 │ │ Specifically, this │ │
1013 │ │ is the operational │ │
1014 │ │ state if an │ │
1015 │ │ incompatible │ │
1016 │ │ program is running │ │
1017 │ │ as system manager │ │
1018 │ │ (PID 1). │ │
1019 ├─────────────┼─────────────────────┼───────────┤
1020 │unknown │ The operational │ > 0 │
1021 │ │ state could not be │ │
1022 │ │ determined, due to │ │
1023 │ │ lack of resources │ │
1024 │ │ or another error │ │
1025 │ │ cause. │ │
1026 └─────────────┴─────────────────────┴───────────┘
1027
1028 default
1029 Enter default mode. This is equivalent to systemctl isolate
1030 default.target. This operation is blocking by default, use
1031 --no-block to request asynchronous behavior.
1032
1033 rescue
1034 Enter rescue mode. This is equivalent to systemctl isolate
1035 rescue.target. This operation is blocking by default, use
1036 --no-block to request asynchronous behavior.
1037
1038 emergency
1039 Enter emergency mode. This is equivalent to systemctl isolate
1040 emergency.target. This operation is blocking by default, use
1041 --no-block to request asynchronous behavior.
1042
1043 halt
1044 Shut down and halt the system. This is mostly equivalent to
1045 systemctl start halt.target --job-mode=replace-irreversibly
1046 --no-block, but also prints a wall message to all users. This
1047 command is asynchronous; it will return after the halt operation is
1048 enqueued, without waiting for it to complete. Note that this
1049 operation will simply halt the OS kernel after shutting down,
1050 leaving the hardware powered on. Use systemctl poweroff for
1051 powering off the system (see below).
1052
1053 If combined with --force, shutdown of all running services is
1054 skipped, however all processes are killed and all file systems are
1055 unmounted or mounted read-only, immediately followed by the system
1056 halt. If --force is specified twice, the operation is immediately
1057 executed without terminating any processes or unmounting any file
1058 systems. This may result in data loss. Note that when --force is
1059 specified twice the halt operation is executed by systemctl itself,
1060 and the system manager is not contacted. This means the command
1061 should succeed even when the system manager has crashed.
1062
1063 poweroff
1064 Shut down and power-off the system. This is mostly equivalent to
1065 systemctl start poweroff.target --job-mode=replace-irreversibly
1066 --no-block, but also prints a wall message to all users. This
1067 command is asynchronous; it will return after the power-off
1068 operation is enqueued, without waiting for it to complete.
1069
1070 If combined with --force, shutdown of all running services is
1071 skipped, however all processes are killed and all file systems are
1072 unmounted or mounted read-only, immediately followed by the
1073 powering off. If --force is specified twice, the operation is
1074 immediately executed without terminating any processes or
1075 unmounting any file systems. This may result in data loss. Note
1076 that when --force is specified twice the power-off operation is
1077 executed by systemctl itself, and the system manager is not
1078 contacted. This means the command should succeed even when the
1079 system manager has crashed.
1080
1081 reboot
1082 Shut down and reboot the system. This is mostly equivalent to
1083 systemctl start reboot.target --job-mode=replace-irreversibly
1084 --no-block, but also prints a wall message to all users. This
1085 command is asynchronous; it will return after the reboot operation
1086 is enqueued, without waiting for it to complete.
1087
1088 If combined with --force, shutdown of all running services is
1089 skipped, however all processes are killed and all file systems are
1090 unmounted or mounted read-only, immediately followed by the reboot.
1091 If --force is specified twice, the operation is immediately
1092 executed without terminating any processes or unmounting any file
1093 systems. This may result in data loss. Note that when --force is
1094 specified twice the reboot operation is executed by systemctl
1095 itself, and the system manager is not contacted. This means the
1096 command should succeed even when the system manager has crashed.
1097
1098 If the switch --reboot-argument= is given, it will be passed as the
1099 optional argument to the reboot(2) system call.
1100
1101 kexec
1102 Shut down and reboot the system via kexec. This is equivalent to
1103 systemctl start kexec.target --job-mode=replace-irreversibly
1104 --no-block. This command is asynchronous; it will return after the
1105 reboot operation is enqueued, without waiting for it to complete.
1106
1107 If combined with --force, shutdown of all running services is
1108 skipped, however all processes are killed and all file systems are
1109 unmounted or mounted read-only, immediately followed by the reboot.
1110
1111 exit [EXIT_CODE]
1112 Ask the service manager to quit. This is only supported for user
1113 service managers (i.e. in conjunction with the --user option) or in
1114 containers and is equivalent to poweroff otherwise. This command is
1115 asynchronous; it will return after the exit operation is enqueued,
1116 without waiting for it to complete.
1117
1118 The service manager will exit with the specified exit code, if
1119 EXIT_CODE is passed.
1120
1121 switch-root ROOT [INIT]
1122 Switches to a different root directory and executes a new system
1123 manager process below it. This is intended for usage in initial RAM
1124 disks ("initrd"), and will transition from the initrd's system
1125 manager process (a.k.a. "init" process) to the main system manager
1126 process which is loaded from the actual host volume. This call
1127 takes two arguments: the directory that is to become the new root
1128 directory, and the path to the new system manager binary below it
1129 to execute as PID 1. If the latter is omitted or the empty string,
1130 a systemd binary will automatically be searched for and used as
1131 init. If the system manager path is omitted, equal to the empty
1132 string or identical to the path to the systemd binary, the state of
1133 the initrd's system manager process is passed to the main system
1134 manager, which allows later introspection of the state of the
1135 services involved in the initrd boot phase.
1136
1137 suspend
1138 Suspend the system. This will trigger activation of the special
1139 target unit suspend.target. This command is asynchronous, and will
1140 return after the suspend operation is successfully enqueued. It
1141 will not wait for the suspend/resume cycle to complete.
1142
1143 hibernate
1144 Hibernate the system. This will trigger activation of the special
1145 target unit hibernate.target. This command is asynchronous, and
1146 will return after the hibernation operation is successfully
1147 enqueued. It will not wait for the hibernate/thaw cycle to
1148 complete.
1149
1150 hybrid-sleep
1151 Hibernate and suspend the system. This will trigger activation of
1152 the special target unit hybrid-sleep.target. This command is
1153 asynchronous, and will return after the hybrid sleep operation is
1154 successfully enqueued. It will not wait for the sleep/wake-up cycle
1155 to complete.
1156
1157 suspend-then-hibernate
1158 Suspend the system and hibernate it after the delay specified in
1159 systemd-sleep.conf. This will trigger activation of the special
1160 target unit suspend-then-hibernate.target. This command is
1161 asynchronous, and will return after the hybrid sleep operation is
1162 successfully enqueued. It will not wait for the sleep/wake-up or
1163 hibernate/thaw cycle to complete.
1164
1165 Parameter Syntax
1166 Unit commands listed above take either a single unit name (designated
1167 as UNIT), or multiple unit specifications (designated as PATTERN...).
1168 In the first case, the unit name with or without a suffix must be
1169 given. If the suffix is not specified (unit name is "abbreviated"),
1170 systemctl will append a suitable suffix, ".service" by default, and a
1171 type-specific suffix in case of commands which operate only on specific
1172 unit types. For example,
1173
1174 # systemctl start sshd
1175
1176 and
1177
1178 # systemctl start sshd.service
1179
1180 are equivalent, as are
1181
1182 # systemctl isolate default
1183
1184 and
1185
1186 # systemctl isolate default.target
1187
1188 Note that (absolute) paths to device nodes are automatically converted
1189 to device unit names, and other (absolute) paths to mount unit names.
1190
1191 # systemctl status /dev/sda
1192 # systemctl status /home
1193
1194 are equivalent to:
1195
1196 # systemctl status dev-sda.device
1197 # systemctl status home.mount
1198
1199 In the second case, shell-style globs will be matched against the
1200 primary names of all units currently in memory; literal unit names,
1201 with or without a suffix, will be treated as in the first case. This
1202 means that literal unit names always refer to exactly one unit, but
1203 globs may match zero units and this is not considered an error.
1204
1205 Glob patterns use fnmatch(3), so normal shell-style globbing rules are
1206 used, and "*", "?", "[]" may be used. See glob(7) for more details. The
1207 patterns are matched against the primary names of units currently in
1208 memory, and patterns which do not match anything are silently skipped.
1209 For example:
1210
1211 # systemctl stop sshd@*.service
1212
1213 will stop all sshd@.service instances. Note that alias names of units,
1214 and units that aren't in memory are not considered for glob expansion.
1215
1216 For unit file commands, the specified UNIT should be the name of the
1217 unit file (possibly abbreviated, see above), or the absolute path to
1218 the unit file:
1219
1220 # systemctl enable foo.service
1221
1222 or
1223
1224 # systemctl link /path/to/foo.service
1225
1226
1228 The following options are understood:
1229
1230 -t, --type=
1231 The argument should be a comma-separated list of unit types such as
1232 service and socket.
1233
1234 If one of the arguments is a unit type, when listing units, limit
1235 display to certain unit types. Otherwise, units of all types will
1236 be shown.
1237
1238 As a special case, if one of the arguments is help, a list of
1239 allowed values will be printed and the program will exit.
1240
1241 --state=
1242 The argument should be a comma-separated list of unit LOAD, SUB, or
1243 ACTIVE states. When listing units, show only those in the specified
1244 states. Use --state=failed to show only failed units.
1245
1246 As a special case, if one of the arguments is help, a list of
1247 allowed values will be printed and the program will exit.
1248
1249 -p, --property=
1250 When showing unit/job/manager properties with the show command,
1251 limit display to properties specified in the argument. The argument
1252 should be a comma-separated list of property names, such as
1253 "MainPID". Unless specified, all known properties are shown. If
1254 specified more than once, all properties with the specified names
1255 are shown. Shell completion is implemented for property names.
1256
1257 For the manager itself, systemctl show will show all available
1258 properties, most of which are derived or closely match the options
1259 described in systemd-system.conf(5).
1260
1261 Properties for units vary by unit type, so showing any unit (even a
1262 non-existent one) is a way to list properties pertaining to this
1263 type. Similarly, showing any job will list properties pertaining to
1264 all jobs. Properties for units are documented in systemd.unit(5),
1265 and the pages for individual unit types systemd.service(5),
1266 systemd.socket(5), etc.
1267
1268 -P
1269 Equivalent to --value --property=, i.e. shows the value of the
1270 property without the property name or "=". Note that using -P once
1271 will also affect all properties listed with -p/--property=.
1272
1273 -a, --all
1274 When listing units with list-units, also show inactive units and
1275 units which are following other units. When showing
1276 unit/job/manager properties, show all properties regardless whether
1277 they are set or not.
1278
1279 To list all units installed in the file system, use the
1280 list-unit-files command instead.
1281
1282 When listing units with list-dependencies, recursively show
1283 dependencies of all dependent units (by default only dependencies
1284 of target units are shown).
1285
1286 When used with status, show journal messages in full, even if they
1287 include unprintable characters or are very long. By default, fields
1288 with unprintable characters are abbreviated as "blob data". (Note
1289 that the pager may escape unprintable characters again.)
1290
1291 -r, --recursive
1292 When listing units, also show units of local containers. Units of
1293 local containers will be prefixed with the container name,
1294 separated by a single colon character (":").
1295
1296 --reverse
1297 Show reverse dependencies between units with list-dependencies,
1298 i.e. follow dependencies of type WantedBy=, RequiredBy=, PartOf=,
1299 BoundBy=, instead of Wants= and similar.
1300
1301 --after
1302 With list-dependencies, show the units that are ordered before the
1303 specified unit. In other words, recursively list units following
1304 the After= dependency.
1305
1306 Note that any After= dependency is automatically mirrored to create
1307 a Before= dependency. Temporal dependencies may be specified
1308 explicitly, but are also created implicitly for units which are
1309 WantedBy= targets (see systemd.target(5)), and as a result of other
1310 directives (for example RequiresMountsFor=). Both explicitly and
1311 implicitly introduced dependencies are shown with
1312 list-dependencies.
1313
1314 When passed to the list-jobs command, for each printed job show
1315 which other jobs are waiting for it. May be combined with --before
1316 to show both the jobs waiting for each job as well as all jobs each
1317 job is waiting for.
1318
1319 --before
1320 With list-dependencies, show the units that are ordered after the
1321 specified unit. In other words, recursively list units following
1322 the Before= dependency.
1323
1324 When passed to the list-jobs command, for each printed job show
1325 which other jobs it is waiting for. May be combined with --after to
1326 show both the jobs waiting for each job as well as all jobs each
1327 job is waiting for.
1328
1329 --with-dependencies
1330 When used with status, cat, list-units, and list-unit-files, those
1331 commands print all specified units and the dependencies of those
1332 units.
1333
1334 Options --reverse, --after, --before may be used to change what
1335 types of dependencies are shown.
1336
1337 -l, --full
1338 Do not ellipsize unit names, process tree entries, journal output,
1339 or truncate unit descriptions in the output of status, list-units,
1340 list-jobs, and list-timers.
1341
1342 Also, show installation targets in the output of is-enabled.
1343
1344 --value
1345 When printing properties with show, only print the value, and skip
1346 the property name and "=". Also see option -P above.
1347
1348 --show-types
1349 When showing sockets, show the type of the socket.
1350
1351 --job-mode=
1352 When queuing a new job, this option controls how to deal with
1353 already queued jobs. It takes one of "fail", "replace",
1354 "replace-irreversibly", "isolate", "ignore-dependencies",
1355 "ignore-requirements", "flush", or "triggering". Defaults to
1356 "replace", except when the isolate command is used which implies
1357 the "isolate" job mode.
1358
1359 If "fail" is specified and a requested operation conflicts with a
1360 pending job (more specifically: causes an already pending start job
1361 to be reversed into a stop job or vice versa), cause the operation
1362 to fail.
1363
1364 If "replace" (the default) is specified, any conflicting pending
1365 job will be replaced, as necessary.
1366
1367 If "replace-irreversibly" is specified, operate like "replace", but
1368 also mark the new jobs as irreversible. This prevents future
1369 conflicting transactions from replacing these jobs (or even being
1370 enqueued while the irreversible jobs are still pending).
1371 Irreversible jobs can still be cancelled using the cancel command.
1372 This job mode should be used on any transaction which pulls in
1373 shutdown.target.
1374
1375 "isolate" is only valid for start operations and causes all other
1376 units to be stopped when the specified unit is started. This mode
1377 is always used when the isolate command is used.
1378
1379 "flush" will cause all queued jobs to be canceled when the new job
1380 is enqueued.
1381
1382 If "ignore-dependencies" is specified, then all unit dependencies
1383 are ignored for this new job and the operation is executed
1384 immediately. If passed, no required units of the unit passed will
1385 be pulled in, and no ordering dependencies will be honored. This is
1386 mostly a debugging and rescue tool for the administrator and should
1387 not be used by applications.
1388
1389 "ignore-requirements" is similar to "ignore-dependencies", but only
1390 causes the requirement dependencies to be ignored, the ordering
1391 dependencies will still be honored.
1392
1393 "triggering" may only be used with systemctl stop. In this mode,
1394 the specified unit and any active units that trigger it are
1395 stopped. See the discussion of Triggers= in systemd.unit(5) for
1396 more information about triggering units.
1397
1398 -T, --show-transaction
1399 When enqueuing a unit job (for example as effect of a systemctl
1400 start invocation or similar), show brief information about all jobs
1401 enqueued, covering both the requested job and any added because of
1402 unit dependencies. Note that the output will only include jobs
1403 immediately part of the transaction requested. It is possible that
1404 service start-up program code run as effect of the enqueued jobs
1405 might request further jobs to be pulled in. This means that
1406 completion of the listed jobs might ultimately entail more jobs
1407 than the listed ones.
1408
1409 --fail
1410 Shorthand for --job-mode=fail.
1411
1412 When used with the kill command, if no units were killed, the
1413 operation results in an error.
1414
1415 --check-inhibitors=
1416 When system shutdown or sleep state is request, this option
1417 controls how to deal with inhibitor locks. It takes one of "auto",
1418 "yes" or "no". Defaults to "auto", which will behave like "yes" for
1419 interactive invocations (i.e. from a TTY) and "no" for
1420 non-interactive invocations. "yes" will let the request respect
1421 inhibitor locks. "no" will let the request ignore inhibitor locks.
1422
1423 Applications can establish inhibitor locks to avoid that certain
1424 important operations (such as CD burning or suchlike) are
1425 interrupted by system shutdown or a sleep state. Any user may take
1426 these locks and privileged users may override these locks. If any
1427 locks are taken, shutdown and sleep state requests will normally
1428 fail (unless privileged) and a list of active locks is printed.
1429 However, if "no" is specified or "auto" is specified on a
1430 non-interactive requests, the established locks are ignored and not
1431 shown, and the operation attempted anyway, possibly requiring
1432 additional privileges. May be overridden by --force.
1433
1434 -i
1435 Shortcut for --check-inhibitors=no.
1436
1437 --dry-run
1438 Just print what would be done. Currently supported by verbs halt,
1439 poweroff, reboot, kexec, suspend, hibernate, hybrid-sleep,
1440 suspend-then-hibernate, default, rescue, emergency, and exit.
1441
1442 -q, --quiet
1443 Suppress printing of the results of various commands and also the
1444 hints about truncated log lines. This does not suppress output of
1445 commands for which the printed output is the only result (like
1446 show). Errors are always printed.
1447
1448 --no-block
1449 Do not synchronously wait for the requested operation to finish. If
1450 this is not specified, the job will be verified, enqueued and
1451 systemctl will wait until the unit's start-up is completed. By
1452 passing this argument, it is only verified and enqueued. This
1453 option may not be combined with --wait.
1454
1455 --wait
1456 Synchronously wait for started units to terminate again. This
1457 option may not be combined with --no-block. Note that this will
1458 wait forever if any given unit never terminates (by itself or by
1459 getting stopped explicitly); particularly services which use
1460 "RemainAfterExit=yes".
1461
1462 When used with is-system-running, wait until the boot process is
1463 completed before returning.
1464
1465 --user
1466 Talk to the service manager of the calling user, rather than the
1467 service manager of the system.
1468
1469 --system
1470 Talk to the service manager of the system. This is the implied
1471 default.
1472
1473 --failed
1474 List units in failed state. This is equivalent to --state=failed.
1475
1476 --no-wall
1477 Do not send wall message before halt, power-off and reboot.
1478
1479 --global
1480 When used with enable and disable, operate on the global user
1481 configuration directory, thus enabling or disabling a unit file
1482 globally for all future logins of all users.
1483
1484 --no-reload
1485 When used with enable and disable, do not implicitly reload daemon
1486 configuration after executing the changes.
1487
1488 --no-ask-password
1489 When used with start and related commands, disables asking for
1490 passwords. Background services may require input of a password or
1491 passphrase string, for example to unlock system hard disks or
1492 cryptographic certificates. Unless this option is specified and the
1493 command is invoked from a terminal, systemctl will query the user
1494 on the terminal for the necessary secrets. Use this option to
1495 switch this behavior off. In this case, the password must be
1496 supplied by some other means (for example graphical password
1497 agents) or the service might fail. This also disables querying the
1498 user for authentication for privileged operations.
1499
1500 --kill-who=
1501 When used with kill, choose which processes to send a signal to.
1502 Must be one of main, control or all to select whether to kill only
1503 the main process, the control process or all processes of the unit.
1504 The main process of the unit is the one that defines the life-time
1505 of it. A control process of a unit is one that is invoked by the
1506 manager to induce state changes of it. For example, all processes
1507 started due to the ExecStartPre=, ExecStop= or ExecReload= settings
1508 of service units are control processes. Note that there is only one
1509 control process per unit at a time, as only one state change is
1510 executed at a time. For services of type Type=forking, the initial
1511 process started by the manager for ExecStart= is a control process,
1512 while the process ultimately forked off by that one is then
1513 considered the main process of the unit (if it can be determined).
1514 This is different for service units of other types, where the
1515 process forked off by the manager for ExecStart= is always the main
1516 process itself. A service unit consists of zero or one main
1517 process, zero or one control process plus any number of additional
1518 processes. Not all unit types manage processes of these types
1519 however. For example, for mount units, control processes are
1520 defined (which are the invocations of /usr/bin/mount and
1521 /usr/bin/umount), but no main process is defined. If omitted,
1522 defaults to all.
1523
1524 -s, --signal=
1525 When used with kill, choose which signal to send to selected
1526 processes. Must be one of the well-known signal specifiers such as
1527 SIGTERM, SIGINT or SIGSTOP. If omitted, defaults to SIGTERM.
1528
1529 The special value "help" will list the known values and the program
1530 will exit immediately, and the special value "list" will list known
1531 values along with the numerical signal numbers and the program will
1532 exit immediately.
1533
1534 --what=
1535 Select what type of per-unit resources to remove when the clean
1536 command is invoked, see below. Takes one of configuration, state,
1537 cache, logs, runtime to select the type of resource. This option
1538 may be specified more than once, in which case all specified
1539 resource types are removed. Also accepts the special value all as a
1540 shortcut for specifying all five resource types. If this option is
1541 not specified defaults to the combination of cache and runtime,
1542 i.e. the two kinds of resources that are generally considered to be
1543 redundant and can be reconstructed on next invocation.
1544
1545 -f, --force
1546 When used with enable, overwrite any existing conflicting symlinks.
1547
1548 When used with edit, create all of the specified units which do not
1549 already exist.
1550
1551 When used with halt, poweroff, reboot or kexec, execute the
1552 selected operation without shutting down all units. However, all
1553 processes will be killed forcibly and all file systems are
1554 unmounted or remounted read-only. This is hence a drastic but
1555 relatively safe option to request an immediate reboot. If --force
1556 is specified twice for these operations (with the exception of
1557 kexec), they will be executed immediately, without terminating any
1558 processes or unmounting any file systems. Warning: specifying
1559 --force twice with any of these operations might result in data
1560 loss. Note that when --force is specified twice the selected
1561 operation is executed by systemctl itself, and the system manager
1562 is not contacted. This means the command should succeed even when
1563 the system manager has crashed.
1564
1565 --message=
1566 When used with halt, poweroff or reboot, set a short message
1567 explaining the reason for the operation. The message will be logged
1568 together with the default shutdown message.
1569
1570 --now
1571 When used with enable, the units will also be started. When used
1572 with disable or mask, the units will also be stopped. The start or
1573 stop operation is only carried out when the respective enable or
1574 disable operation has been successful.
1575
1576 --root=
1577 When used with enable/disable/is-enabled (and related commands),
1578 use the specified root path when looking for unit files. If this
1579 option is present, systemctl will operate on the file system
1580 directly, instead of communicating with the systemd daemon to carry
1581 out changes.
1582
1583 --runtime
1584 When used with enable, disable, edit, (and related commands), make
1585 changes only temporarily, so that they are lost on the next reboot.
1586 This will have the effect that changes are not made in
1587 subdirectories of /etc/ but in /run/, with identical immediate
1588 effects, however, since the latter is lost on reboot, the changes
1589 are lost too.
1590
1591 Similarly, when used with set-property, make changes only
1592 temporarily, so that they are lost on the next reboot.
1593
1594 --preset-mode=
1595 Takes one of "full" (the default), "enable-only", "disable-only".
1596 When used with the preset or preset-all commands, controls whether
1597 units shall be disabled and enabled according to the preset rules,
1598 or only enabled, or only disabled.
1599
1600 -n, --lines=
1601 When used with status, controls the number of journal lines to
1602 show, counting from the most recent ones. Takes a positive integer
1603 argument, or 0 to disable journal output. Defaults to 10.
1604
1605 -o, --output=
1606 When used with status, controls the formatting of the journal
1607 entries that are shown. For the available choices, see
1608 journalctl(1). Defaults to "short".
1609
1610 --firmware-setup
1611 When used with the reboot command, indicate to the system's
1612 firmware to reboot into the firmware setup interface. Note that
1613 this functionality is not available on all systems.
1614
1615 --boot-loader-menu=
1616 When used with the reboot command, indicate to the system's boot
1617 loader to show the boot loader menu on the following boot. Takes a
1618 time value as parameter — indicating the menu timeout. Pass zero in
1619 order to disable the menu timeout. Note that not all boot loaders
1620 support this functionality.
1621
1622 --boot-loader-entry=
1623 When used with the reboot command, indicate to the system's boot
1624 loader to boot into a specific boot loader entry on the following
1625 boot. Takes a boot loader entry identifier as argument, or "help"
1626 in order to list available entries. Note that not all boot loaders
1627 support this functionality.
1628
1629 --reboot-argument=
1630 This switch is used with reboot. The value is architecture and
1631 firmware specific. As an example, "recovery" might be used to
1632 trigger system recovery, and "fota" might be used to trigger a
1633 “firmware over the air” update.
1634
1635 --plain
1636 When used with list-dependencies, list-units or list-machines, the
1637 output is printed as a list instead of a tree, and the bullet
1638 circles are omitted.
1639
1640 --timestamp=
1641 Change the format of printed timestamps. The following values may
1642 be used:
1643
1644 pretty (this is the default)
1645 "Day YYYY-MM-DD HH:MM:SS TZ"
1646
1647 us, µs
1648 "Day YYYY-MM-DD HH:MM:SS.UUUUUU TZ"
1649
1650 utc
1651 "Day YYYY-MM-DD HH:MM:SS UTC"
1652
1653 us+utc, µs+utc
1654 "Day YYYY-MM-DD HH:MM:SS.UUUUUU UTC"
1655
1656 --mkdir
1657 When used with bind, creates the destination file or directory
1658 before applying the bind mount. Note that even though the name of
1659 this option suggests that it is suitable only for directories, this
1660 option also creates the destination file node to mount over if the
1661 object to mount is not a directory, but a regular file, device
1662 node, socket or FIFO.
1663
1664 --marked
1665 Only allowed with reload-or-restart. Enqueues restart jobs for all
1666 units that have the "needs-restart" mark, and reload jobs for units
1667 that have the "needs-reload" mark. When a unit marked for reload
1668 does not support reload, restart will be queued. Those properties
1669 can be set using set-property Marks.
1670
1671 Unless --no-block is used, systemctl will wait for the queued jobs
1672 to finish.
1673
1674 --read-only
1675 When used with bind, creates a read-only bind mount.
1676
1677 -H, --host=
1678 Execute the operation remotely. Specify a hostname, or a username
1679 and hostname separated by "@", to connect to. The hostname may
1680 optionally be suffixed by a port ssh is listening on, separated by
1681 ":", and then a container name, separated by "/", which connects
1682 directly to a specific container on the specified host. This will
1683 use SSH to talk to the remote machine manager instance. Container
1684 names may be enumerated with machinectl -H HOST. Put IPv6 addresses
1685 in brackets.
1686
1687 -M, --machine=
1688 Execute operation on a local container. Specify a container name to
1689 connect to, optionally prefixed by a user name to connect as and a
1690 separating "@" character. If the special string ".host" is used in
1691 place of the container name, a connection to the local system is
1692 made (which is useful to connect to a specific user's user bus:
1693 "--user --machine=lennart@.host"). If the "@" syntax is not used,
1694 the connection is made as root user. If the "@" syntax is used
1695 either the left hand side or the right hand side may be omitted
1696 (but not both) in which case the local user name and ".host" are
1697 implied.
1698
1699 --no-pager
1700 Do not pipe output into a pager.
1701
1702 --legend=BOOL
1703 Enable or disable printing of the legend, i.e. column headers and
1704 the footer with hints. The legend is printed by default, unless
1705 disabled with --quiet or similar.
1706
1707 -h, --help
1708 Print a short help text and exit.
1709
1710 --version
1711 Print a short version string and exit.
1712
1714 On success, 0 is returned, a non-zero failure code otherwise.
1715
1716 systemctl uses the return codes defined by LSB, as defined in LSB
1717 3.0.0[1].
1718
1719 Table 3. LSB return codes
1720 ┌──────┬─────────────────────┬─────────────────────┐
1721 │Value │ Description in LSB │ Use in systemd │
1722 ├──────┼─────────────────────┼─────────────────────┤
1723 │0 │ "program is running │ unit is active │
1724 │ │ or service is OK" │ │
1725 ├──────┼─────────────────────┼─────────────────────┤
1726 │1 │ "program is dead │ unit not failed │
1727 │ │ and /var/run pid │ (used by is-failed) │
1728 │ │ file exists" │ │
1729 ├──────┼─────────────────────┼─────────────────────┤
1730 │2 │ "program is dead │ unused │
1731 │ │ and /var/lock lock │ │
1732 │ │ file exists" │ │
1733 ├──────┼─────────────────────┼─────────────────────┤
1734 │3 │ "program is not │ unit is not active │
1735 │ │ running" │ │
1736 ├──────┼─────────────────────┼─────────────────────┤
1737 │4 │ "program or service │ no such unit │
1738 │ │ status is unknown" │ │
1739 └──────┴─────────────────────┴─────────────────────┘
1740
1741 The mapping of LSB service states to systemd unit states is imperfect,
1742 so it is better to not rely on those return values but to look for
1743 specific unit states and substates instead.
1744
1746 $SYSTEMD_EDITOR
1747 Editor to use when editing units; overrides $EDITOR and $VISUAL. If
1748 neither $SYSTEMD_EDITOR nor $EDITOR nor $VISUAL are present or if
1749 it is set to an empty string or if their execution failed,
1750 systemctl will try to execute well known editors in this order:
1751 editor(1), nano(1), vim(1), vi(1).
1752
1753 $SYSTEMD_LOG_LEVEL
1754 The maximum log level of emitted messages (messages with a higher
1755 log level, i.e. less important ones, will be suppressed). Either
1756 one of (in order of decreasing importance) emerg, alert, crit, err,
1757 warning, notice, info, debug, or an integer in the range 0...7. See
1758 syslog(3) for more information.
1759
1760 $SYSTEMD_LOG_COLOR
1761 A boolean. If true, messages written to the tty will be colored
1762 according to priority.
1763
1764 This setting is only useful when messages are written directly to
1765 the terminal, because journalctl(1) and other tools that display
1766 logs will color messages based on the log level on their own.
1767
1768 $SYSTEMD_LOG_TIME
1769 A boolean. If true, console log messages will be prefixed with a
1770 timestamp.
1771
1772 This setting is only useful when messages are written directly to
1773 the terminal or a file, because journalctl(1) and other tools that
1774 display logs will attach timestamps based on the entry metadata on
1775 their own.
1776
1777 $SYSTEMD_LOG_LOCATION
1778 A boolean. If true, messages will be prefixed with a filename and
1779 line number in the source code where the message originates.
1780
1781 Note that the log location is often attached as metadata to journal
1782 entries anyway. Including it directly in the message text can
1783 nevertheless be convenient when debugging programs.
1784
1785 $SYSTEMD_LOG_TARGET
1786 The destination for log messages. One of console (log to the
1787 attached tty), console-prefixed (log to the attached tty but with
1788 prefixes encoding the log level and "facility", see syslog(3), kmsg
1789 (log to the kernel circular log buffer), journal (log to the
1790 journal), journal-or-kmsg (log to the journal if available, and to
1791 kmsg otherwise), auto (determine the appropriate log target
1792 automatically, the default), null (disable log output).
1793
1794 $SYSTEMD_PAGER
1795 Pager to use when --no-pager is not given; overrides $PAGER. If
1796 neither $SYSTEMD_PAGER nor $PAGER are set, a set of well-known
1797 pager implementations are tried in turn, including less(1) and
1798 more(1), until one is found. If no pager implementation is
1799 discovered no pager is invoked. Setting this environment variable
1800 to an empty string or the value "cat" is equivalent to passing
1801 --no-pager.
1802
1803 $SYSTEMD_LESS
1804 Override the options passed to less (by default "FRSXMK").
1805
1806 Users might want to change two options in particular:
1807
1808 K
1809 This option instructs the pager to exit immediately when Ctrl+C
1810 is pressed. To allow less to handle Ctrl+C itself to switch
1811 back to the pager command prompt, unset this option.
1812
1813 If the value of $SYSTEMD_LESS does not include "K", and the
1814 pager that is invoked is less, Ctrl+C will be ignored by the
1815 executable, and needs to be handled by the pager.
1816
1817 X
1818 This option instructs the pager to not send termcap
1819 initialization and deinitialization strings to the terminal. It
1820 is set by default to allow command output to remain visible in
1821 the terminal even after the pager exits. Nevertheless, this
1822 prevents some pager functionality from working, in particular
1823 paged output cannot be scrolled with the mouse.
1824
1825 See less(1) for more discussion.
1826
1827 $SYSTEMD_LESSCHARSET
1828 Override the charset passed to less (by default "utf-8", if the
1829 invoking terminal is determined to be UTF-8 compatible).
1830
1831 $SYSTEMD_PAGERSECURE
1832 Takes a boolean argument. When true, the "secure" mode of the pager
1833 is enabled; if false, disabled. If $SYSTEMD_PAGERSECURE is not set
1834 at all, secure mode is enabled if the effective UID is not the same
1835 as the owner of the login session, see geteuid(2) and
1836 sd_pid_get_owner_uid(3). In secure mode, LESSSECURE=1 will be set
1837 when invoking the pager, and the pager shall disable commands that
1838 open or create new files or start new subprocesses. When
1839 $SYSTEMD_PAGERSECURE is not set at all, pagers which are not known
1840 to implement secure mode will not be used. (Currently only less(1)
1841 implements secure mode.)
1842
1843 Note: when commands are invoked with elevated privileges, for
1844 example under sudo(8) or pkexec(1), care must be taken to ensure
1845 that unintended interactive features are not enabled. "Secure" mode
1846 for the pager may be enabled automatically as describe above.
1847 Setting SYSTEMD_PAGERSECURE=0 or not removing it from the inherited
1848 environment allows the user to invoke arbitrary commands. Note that
1849 if the $SYSTEMD_PAGER or $PAGER variables are to be honoured,
1850 $SYSTEMD_PAGERSECURE must be set too. It might be reasonable to
1851 completely disable the pager using --no-pager instead.
1852
1853 $SYSTEMD_COLORS
1854 Takes a boolean argument. When true, systemd and related utilities
1855 will use colors in their output, otherwise the output will be
1856 monochrome. Additionally, the variable can take one of the
1857 following special values: "16", "256" to restrict the use of colors
1858 to the base 16 or 256 ANSI colors, respectively. This can be
1859 specified to override the automatic decision based on $TERM and
1860 what the console is connected to.
1861
1862 $SYSTEMD_URLIFY
1863 The value must be a boolean. Controls whether clickable links
1864 should be generated in the output for terminal emulators supporting
1865 this. This can be specified to override the decision that systemd
1866 makes based on $TERM and other conditions.
1867
1869 systemd(1), journalctl(1), loginctl(1), machinectl(1), systemd.unit(5),
1870 systemd.resource-control(5), systemd.special(7), wall(1),
1871 systemd.preset(5), systemd.generator(7), glob(7)
1872
1874 1. LSB 3.0.0
1875 http://refspecs.linuxbase.org/LSB_3.0.0/LSB-PDA/LSB-PDA/iniscrptact.html
1876
1877
1878
1879systemd 250 SYSTEMCTL(1)