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SYSTEMCTL(1)                       systemctl                      SYSTEMCTL(1)

NAME
       systemctl - Control the systemd system and service manager

SYNOPSIS
       systemctl [OPTIONS...] COMMAND [UNIT...]

DESCRIPTION
       systemctl may be used to introspect and control the state of the
       "systemd" system and service manager. Please refer to systemd(1) for an
       introduction into the basic concepts and functionality this tool
       manages.

COMMANDS
       The following commands are understood:

   Unit Commands
       list-units [PATTERN...]
           List units that systemd currently has in memory. This includes
           units that are either referenced directly or through a dependency,
           units that are pinned by applications programmatically, or units
           that were active in the past and have failed. By default only units
           which are active, have pending jobs, or have failed are shown; this
           can be changed with option --all. If one or more PATTERNs are
           specified, only units matching one of them are shown. The units
           that are shown are additionally filtered by --type= and --state= if
           those options are specified.

           Produces output similar to

                 UNIT                         LOAD   ACTIVE SUB     DESCRIPTION
                 sys-module-fuse.device       loaded active plugged /sys/module/fuse
                 -.mount                      loaded active mounted Root Mount
                 boot-efi.mount               loaded active mounted /boot/efi
                 systemd-journald.service     loaded active running Journal Service
                 systemd-logind.service       loaded active running Login Service
                user@1000.service            loaded failed failed  User Manager for UID 1000
                 ...
                 systemd-tmpfiles-clean.timer loaded active waiting Daily Cleanup of Temporary Directories

               LOAD   = Reflects whether the unit definition was properly loaded.
               ACTIVE = The high-level unit activation state, i.e. generalization of SUB.
               SUB    = The low-level unit activation state, values depend on unit type.

               123 loaded units listed. Pass --all to see loaded but inactive units, too.
               To show all installed unit files use 'systemctl list-unit-files'.

           The header and the last unit of a given type are underlined if the
           terminal supports that. A colored dot is shown next to services
           which were masked, not found, or otherwise failed.

           The LOAD column shows the load state, one of loaded, not-found,
           bad-setting, error, masked. The ACTIVE columns shows the general
           unit state, one of active, reloading, inactive, failed, activating,
           deactivating. The SUB column shows the unit-type-specific detailed
           state of the unit, possible values vary by unit type. The list of
           possible LOAD, ACTIVE, and SUB states is not constant and new
           systemd releases may both add and remove values.

               systemctl --state=help

           command maybe be used to display the current set of possible
           values.

           This is the default command.

       list-sockets [PATTERN...]
           List socket units currently in memory, ordered by listening
           address. If one or more PATTERNs are specified, only socket units
           matching one of them are shown. Produces output similar to

               LISTEN           UNIT                        ACTIVATES
               /dev/initctl     systemd-initctl.socket      systemd-initctl.service
               ...
               [::]:22          sshd.socket                 sshd.service
               kobject-uevent 1 systemd-udevd-kernel.socket systemd-udevd.service

               5 sockets listed.

           Note: because the addresses might contains spaces, this output is
           not suitable for programmatic consumption.

           Also see --show-types, --all, and --state=.

       list-timers [PATTERN...]
           List timer units currently in memory, ordered by the time they
           elapse next. If one or more PATTERNs are specified, only units
           matching one of them are shown. Produces output similar to

               NEXT                         LEFT          LAST                         PASSED     UNIT                         ACTIVATES
               n/a                          n/a           Thu 2017-02-23 13:40:29 EST  3 days ago ureadahead-stop.timer        ureadahead-stop.service
               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
               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
               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

           NEXT shows the next time the timer will run.

           LEFT shows how long till the next time the timer runs.

           LAST shows the last time the timer ran.

           PASSED shows how long has passed since the timer last ran.

           UNIT shows the name of the timer

           ACTIVATES shows the name the service the timer activates when it
           runs.

           Also see --all and --state=.

       start PATTERN...
           Start (activate) one or more units specified on the command line.

           Note that unit glob patterns expand to names of units currently in
           memory. Units which are not active and are not in a failed state
           usually are not in memory, and will not be matched by any pattern.
           In addition, in case of instantiated units, systemd is often
           unaware of the instance name until the instance has been started.
           Therefore, using glob patterns with start has limited usefulness.
           Also, secondary alias names of units are not considered.

           Option --all may be used to also operate on inactive units which
           are referenced by other loaded units. Note that this is not the
           same as operating on "all" possible units, because as the previous
           paragraph describes, such a list is ill-defined. Nevertheless,
           systemctl start --all GLOB may be useful if all the units that
           should match the pattern are pulled in by some target which is
           known to be loaded.

       stop PATTERN...
           Stop (deactivate) one or more units specified on the command line.

           This command will fail if the unit does not exist or if stopping of
           the unit is prohibited (see RefuseManualStop= in systemd.unit(5)).
           It will not fail if any of the commands configured to stop the unit
           (ExecStop=, etc.) fail, because the manager will still forcibly
           terminate the unit.

       reload PATTERN...
           Asks all units listed on the command line to reload their
           configuration. Note that this will reload the service-specific
           configuration, not the unit configuration file of systemd. If you
           want systemd to reload the configuration file of a unit, use the
           daemon-reload command. In other words: for the example case of
           Apache, this will reload Apache's httpd.conf in the web server, not
           the apache.service systemd unit file.

           This command should not be confused with the daemon-reload command.

       restart PATTERN...
           Stop and then start one or more units specified on the command
           line. If the units are not running yet, they will be started.

           Note that restarting a unit with this command does not necessarily
           flush out all of the unit's resources before it is started again.
           For example, the per-service file descriptor storage facility (see
           FileDescriptorStoreMax= in systemd.service(5)) will remain intact
           as long as the unit has a job pending, and is only cleared when the
           unit is fully stopped and no jobs are pending anymore. If it is
           intended that the file descriptor store is flushed out, too, during
           a restart operation an explicit systemctl stop command followed by
           systemctl start should be issued.

       try-restart PATTERN...
           Stop and then start one or more units specified on the command line
           if the units are running. This does nothing if units are not
           running.

       reload-or-restart PATTERN...
           Reload one or more units if they support it. If not, stop and then
           start them instead. If the units are not running yet, they will be
           started.

       try-reload-or-restart PATTERN...
           Reload one or more units if they support it. If not, stop and then
           start them instead. This does nothing if the units are not running.

       isolate UNIT
           Start the unit specified on the command line and its dependencies
           and stop all others, unless they have IgnoreOnIsolate=yes (see
           systemd.unit(5)). If a unit name with no extension is given, an
           extension of ".target" will be assumed.

           This is similar to changing the runlevel in a traditional init
           system. The isolate command will immediately stop processes that
           are not enabled in the new unit, possibly including the graphical
           environment or terminal you are currently using.

           Note that this is allowed only on units where AllowIsolate= is
           enabled. See systemd.unit(5) for details.

       kill PATTERN...
           Send a signal to one or more processes of the unit. Use --kill-who=
           to select which process to kill. Use --signal= to select the signal
           to send.

       clean PATTERN...
           Remove the configuration, state, cache, logs or runtime data of the
           specified units. Use --what= to select which kind of resource to
           remove. For service units this may be used to remove the
           directories configured with ConfigurationDirectory=,
           StateDirectory=, CacheDirectory=, LogsDirectory= and
           RuntimeDirectory=, see systemd.exec(5) for details. For timer units
           this may be used to clear out the persistent timestamp data if
           Persistent= is used and --what=state is selected, see
           systemd.timer(5). This command only applies to units that use
           either of these settings. If --what= is not specified, both the
           cache and runtime data are removed (as these two types of data are
           generally redundant and reproducible on the next invocation of the
           unit).

       is-active PATTERN...
           Check whether any of the specified units are active (i.e. running).
           Returns an exit code 0 if at least one is active, or non-zero
           otherwise. Unless --quiet is specified, this will also print the
           current unit state to standard output.

       is-failed PATTERN...
           Check whether any of the specified units are in a "failed" state.
           Returns an exit code 0 if at least one has failed, non-zero
           otherwise. Unless --quiet is specified, this will also print the
           current unit state to standard output.

       status [PATTERN...|PID...]]
           Show terse runtime status information about one or more units,
           followed by most recent log data from the journal. If no units are
           specified, show system status. If combined with --all, also show
           the status of all units (subject to limitations specified with -t).
           If a PID is passed, show information about the unit the process
           belongs to.

           This function is intended to generate human-readable output. If you
           are looking for computer-parsable output, use show instead. By
           default, this function only shows 10 lines of output and ellipsizes
           lines to fit in the terminal window. This can be changed with
           --lines and --full, see above. In addition, journalctl --unit=NAME
           or journalctl --user-unit=NAME use a similar filter for messages
           and might be more convenient.

           systemd implicitly loads units as necessary, so just running the
           status will attempt to load a file. The command is thus not useful
           for determining if something was already loaded or not. The units
           may possibly also be quickly unloaded after the operation is
           completed if there's no reason to keep it in memory thereafter.

           Example 1. Example output from systemctl status

               $ systemctl status bluetooth
                bluetooth.service - Bluetooth service
                  Loaded: loaded (/lib/systemd/system/bluetooth.service; enabled; vendor preset: enabled)
                  Active: active (running) since Wed 2017-01-04 13:54:04 EST; 1 weeks 0 days ago
                    Docs: man:bluetoothd(8)
                Main PID: 930 (bluetoothd)
                  Status: "Running"
                   Tasks: 1
                  Memory: 648.0K
                     CPU: 435ms
                  CGroup: /system.slice/bluetooth.service
                          930 /usr/lib/bluetooth/bluetoothd

               Jan 12 10:46:45 example.com bluetoothd[8900]: Not enough free handles to register service
               Jan 12 10:46:45 example.com bluetoothd[8900]: Current Time Service could not be registered
               Jan 12 10:46:45 example.com bluetoothd[8900]: gatt-time-server: Input/output error (5)

           The dot ("") uses color on supported terminals to summarize the
           unit state at a glance. White indicates an "inactive" or
           "deactivating" state. Red indicates a "failed" or "error" state and
           green indicates an "active", "reloading" or "activating" state.

           The "Loaded:" line in the output will show "loaded" if the unit has
           been loaded into memory. Other possible values for "Loaded:"
           include: "error" if there was a problem loading it, "not-found" if
           not unit file was found for this unit, "bad-setting" if an
           essential unit file setting could not be parsed and "masked" if the
           unit file has been masked. Along with showing the path to the unit
           file, this line will also show the enablement state. Enabled
           commands start at boot. See the full table of possible enablement
           states -- including the definition of "masked" -- in the
           documentation for the is-enabled command.

           The "Active:" line shows active state. The value is usually
           "active" or "inactive". Active could mean started, bound, plugged
           in, etc depending on the unit type. The unit could also be in
           process of changing states, reporting a state of "activating" or
           "deactivating". A special "failed" state is entered when the
           service failed in some way, such as a crash, exiting with an error
           code or timing out. If the failed state is entered the cause will
           be logged for later reference.

       show [PATTERN...|JOB...]
           Show properties of one or more units, jobs, or the manager itself.
           If no argument is specified, properties of the manager will be
           shown. If a unit name is specified, properties of the unit are
           shown, and if a job ID is specified, properties of the job are
           shown. By default, empty properties are suppressed. Use --all to
           show those too. To select specific properties to show, use
           --property=. This command is intended to be used whenever
           computer-parsable output is required. Use status if you are looking
           for formatted human-readable output.

           Many properties shown by systemctl show map directly to
           configuration settings of the system and service manager and its
           unit files. Note that the properties shown by the command are
           generally more low-level, normalized versions of the original
           configuration settings and expose runtime state in addition to
           configuration. For example, properties shown for service units
           include the service's current main process identifier as "MainPID"
           (which is runtime state), and time settings are always exposed as
           properties ending in the "...USec" suffix even if a matching
           configuration options end in "...Sec", because microseconds is the
           normalized time unit used by the system and service manager.

       cat PATTERN...
           Show backing files of one or more units. Prints the "fragment" and
           "drop-ins" (source files) of units. Each file is preceded by a
           comment which includes the file name. Note that this shows the
           contents of the backing files on disk, which may not match the
           system manager's understanding of these units if any unit files
           were updated on disk and the daemon-reload command wasn't issued
           since.

       set-property UNIT PROPERTY=VALUE...
           Set the specified unit properties at runtime where this is
           supported. This allows changing configuration parameter properties
           such as resource control settings at runtime. Not all properties
           may be changed at runtime, but many resource control settings
           (primarily those in systemd.resource-control(5)) may. The changes
           are applied immediately, and stored on disk for future boots,
           unless --runtime is passed, in which case the settings only apply
           until the next reboot. The syntax of the property assignment
           follows closely the syntax of assignments in unit files.

           Example: systemctl set-property foobar.service CPUWeight=200

           If the specified unit appears to be inactive, the changes will be
           only stored on disk as described previously hence they will be
           effective when the unit will be started.

           Note that this command allows changing multiple properties at the
           same time, which is preferable over setting them individually.

           Example: systemctl set-property foobar.service CPUWeight=200
           MemoryMax=2G IPAccounting=yes

           Like with unit file configuration settings, assigning an empty
           setting usually resets a property to its defaults.

           Example: systemctl set-property avahi-daemon.service IPAddressDeny=

       help PATTERN...|PID...
           Show manual pages for one or more units, if available. If a PID is
           given, the manual pages for the unit the process belongs to are
           shown.

       reset-failed [PATTERN...]
           Reset the "failed" state of the specified units, or if no unit name
           is passed, reset the state of all units. When a unit fails in some
           way (i.e. process exiting with non-zero error code, terminating
           abnormally or timing out), it will automatically enter the "failed"
           state and its exit code and status is recorded for introspection by
           the administrator until the service is stopped/re-started or reset
           with this command.

           In addition to resetting the "failed" state of a unit it also
           resets various other per-unit properties: the start rate limit
           counter of all unit types is reset to zero, as is the restart
           counter of service units. Thus, if a unit's start limit (as
           configured with StartLimitIntervalSec=/StartLimitBurst=) is hit and
           the unit refuses to be started again, use this command to make it
           startable again.

       list-dependencies [UNIT...]
           Shows units required and wanted by the specified units. This
           recursively lists units following the Requires=, Requisite=,
           ConsistsOf=, Wants=, BindsTo= dependencies. If no units are
           specified, default.target is implied.

           By default, only target units are recursively expanded. When --all
           is passed, all other units are recursively expanded as well.

           Options --reverse, --after, --before may be used to change what
           types of dependencies are shown.

           Note that this command only lists units currently loaded into
           memory by the service manager. In particular, this command is not
           suitable to get a comprehensive list at all reverse dependencies on
           a specific unit, as it won't list the dependencies declared by
           units currently not loaded.

   Unit File Commands
       list-unit-files [PATTERN...]
           List unit files installed on the system, in combination with their
           enablement state (as reported by is-enabled). If one or more
           PATTERNs are specified, only unit files whose name matches one of
           them are shown (patterns matching unit file system paths are not
           supported).

       enable UNIT..., enable PATH...
           Enable one or more units or unit instances. This will create a set
           of symlinks, as encoded in the "[Install]" sections of the
           indicated unit files. After the symlinks have been created, the
           system manager configuration is reloaded (in a way equivalent to
           daemon-reload), in order to ensure the changes are taken into
           account immediately. Note that this does not have the effect of
           also starting any of the units being enabled. If this is desired,
           combine this command with the --now switch, or invoke start with
           appropriate arguments later. Note that in case of unit instance
           enablement (i.e. enablement of units of the form foo@bar.service),
           symlinks named the same as instances are created in the unit
           configuration directory, however they point to the single template
           unit file they are instantiated from.

           This command expects either valid unit names (in which case various
           unit file directories are automatically searched for unit files
           with appropriate names), or absolute paths to unit files (in which
           case these files are read directly). If a specified unit file is
           located outside of the usual unit file directories, an additional
           symlink is created, linking it into the unit configuration path,
           thus ensuring it is found when requested by commands such as start.
           The file system where the linked unit files are located must be
           accessible when systemd is started (e.g. anything underneath /home
           or /var is not allowed, unless those directories are located on the
           root file system).

           This command will print the file system operations executed. This
           output may be suppressed by passing --quiet.

           Note that this operation creates only the symlinks suggested in the
           "[Install]" section of the unit files. While this command is the
           recommended way to manipulate the unit configuration directory, the
           administrator is free to make additional changes manually by
           placing or removing symlinks below this directory. This is
           particularly useful to create configurations that deviate from the
           suggested default installation. In this case, the administrator
           must make sure to invoke daemon-reload manually as necessary, in
           order to ensure the changes are taken into account.

           Enabling units should not be confused with starting (activating)
           units, as done by the start command. Enabling and starting units is
           orthogonal: units may be enabled without being started and started
           without being enabled. Enabling simply hooks the unit into various
           suggested places (for example, so that the unit is automatically
           started on boot or when a particular kind of hardware is plugged
           in). Starting actually spawns the daemon process (in case of
           service units), or binds the socket (in case of socket units), and
           so on.

           Depending on whether --system, --user, --runtime, or --global is
           specified, this enables the unit for the system, for the calling
           user only, for only this boot of the system, or for all future
           logins of all users. Note that in the last case, no systemd daemon
           configuration is reloaded.

           Using enable on masked units is not supported and results in an
           error.

       disable UNIT...
           Disables one or more units. This removes all symlinks to the unit
           files backing the specified units from the unit configuration
           directory, and hence undoes any changes made by enable or link.
           Note that this removes all symlinks to matching unit files,
           including manually created symlinks, and not just those actually
           created by enable or link. Note that while disable undoes the
           effect of enable, the two commands are otherwise not symmetric, as
           disable may remove more symlinks than a prior enable invocation of
           the same unit created.

           This command expects valid unit names only, it does not accept
           paths to unit files.

           In addition to the units specified as arguments, all units are
           disabled that are listed in the Also= setting contained in the
           "[Install]" section of any of the unit files being operated on.

           This command implicitly reloads the system manager configuration
           after completing the operation. Note that this command does not
           implicitly stop the units that are being disabled. If this is
           desired, either combine this command with the --now switch, or
           invoke the stop command with appropriate arguments later.

           This command will print information about the file system
           operations (symlink removals) executed. This output may be
           suppressed by passing --quiet.

           This command honors --system, --user, --runtime and --global in a
           similar way as enable.

       reenable UNIT...
           Reenable one or more units, as specified on the command line. This
           is a combination of disable and enable and is useful to reset the
           symlinks a unit file is enabled with to the defaults configured in
           its "[Install]" section. This command expects a unit name only, it
           does not accept paths to unit files.

       preset UNIT...
           Reset the enable/disable status one or more unit files, as
           specified on the command line, to the defaults configured in the
           preset policy files. This has the same effect as disable or enable,
           depending how the unit is listed in the preset files.

           Use --preset-mode= to control whether units shall be enabled and
           disabled, or only enabled, or only disabled.

           If the unit carries no install information, it will be silently
           ignored by this command.  UNIT must be the real unit name, any
           alias names are ignored silently.

           For more information on the preset policy format, see
           systemd.preset(5). For more information on the concept of presets,
           please consult the Preset[1] document.

       preset-all
           Resets all installed unit files to the defaults configured in the
           preset policy file (see above).

           Use --preset-mode= to control whether units shall be enabled and
           disabled, or only enabled, or only disabled.

       is-enabled UNIT...
           Checks whether any of the specified unit files are enabled (as with
           enable). Returns an exit code of 0 if at least one is enabled,
           non-zero otherwise. Prints the current enable status (see table).
           To suppress this output, use --quiet. To show installation targets,
           use --full.

           Table 1.  is-enabled output
           +------------------+-------------------------+-----------+
           |Name              | Description             | Exit Code |
           +------------------+-------------------------+-----------+
           |"enabled"         | Enabled via             |           |
           +------------------+ .wants/, .requires/     |           |
           |"enabled-runtime" | or Alias= symlinks      |           |
           |                  | (permanently in         | 0         |
           |                  | /etc/systemd/system/,   |           |
           |                  | or transiently in       |           |
           |                  | /run/systemd/system/).  |           |
           +------------------+-------------------------+-----------+
           |"linked"          | Made available through  |           |
           +------------------+ one or more symlinks    |           |
           |"linked-runtime"  | to the unit file        |           |
           |                  | (permanently in         |           |
           |                  | /etc/systemd/system/    |           |
           |                  | or transiently in       | > 0       |
           |                  | /run/systemd/system/),  |           |
           |                  | even though the unit    |           |
           |                  | file might reside       |           |
           |                  | outside of the unit     |           |
           |                  | file search path.       |           |
           +------------------+-------------------------+-----------+
           |"masked"          | Completely disabled,    |           |
           +------------------+ so that any start       |           |
           |"masked-runtime"  | operation on it fails   |           |
           |                  | (permanently in         | > 0       |
           |                  | /etc/systemd/system/    |           |
           |                  | or transiently in       |           |
           |                  | /run/systemd/systemd/). |           |
           +------------------+-------------------------+-----------+
           |"static"          | The unit file is not    | 0         |
           |                  | enabled, and has no     |           |
           |                  | provisions for enabling |           |
           |                  | in the "[Install]" unit |           |
           |                  | file section.           |           |
           +------------------+-------------------------+-----------+
           |"indirect"        | The unit file itself is | 0         |
           |                  | not enabled, but it has |           |
           |                  | a non-empty Also=       |           |
           |                  | setting in the          |           |
           |                  | "[Install]" unit file   |           |
           |                  | section, listing other  |           |
           |                  | unit files that might   |           |
           |                  | be enabled, or it has   |           |
           |                  | an alias under a        |           |
           |                  | different name through  |           |
           |                  | a symlink that is not   |           |
           |                  | specified in Also=. For |           |
           |                  | template unit file, an  |           |
           |                  | instance different than |           |
           |                  | the one specified in    |           |
           |                  | DefaultInstance= is     |           |
           |                  | enabled.                |           |
           +------------------+-------------------------+-----------+
           |"disabled"        | The unit file is not    | > 0       |
           |                  | enabled, but contains   |           |
           |                  | an "[Install]" section  |           |
           |                  | with installation       |           |
           |                  | instructions.           |           |
           +------------------+-------------------------+-----------+
           |"generated"       | The unit file was       | 0         |
           |                  | generated dynamically   |           |
           |                  | via a generator tool.   |           |
           |                  | See                     |           |
           |                  | systemd.generator(7).   |           |
           |                  | Generated unit files    |           |
           |                  | may not be enabled,     |           |
           |                  | they are enabled        |           |
           |                  | implicitly by their     |           |
           |                  | generator.              |           |
           +------------------+-------------------------+-----------+
           |"transient"       | The unit file has been  | 0         |
           |                  | created dynamically     |           |
           |                  | with the runtime API.   |           |
           |                  | Transient units may not |           |
           |                  | be enabled.             |           |
           +------------------+-------------------------+-----------+
           |"bad"             | The unit file is        | > 0       |
           |                  | invalid or another      |           |
           |                  | error occurred. Note    |           |
           |                  | that is-enabled will    |           |
           |                  | not actually return     |           |
           |                  | this state, but print   |           |
           |                  | an error message        |           |
           |                  | instead. However the    |           |
           |                  | unit file listing       |           |
           |                  | printed by              |           |
           |                  | list-unit-files might   |           |
           |                  | show it.                |           |
           +------------------+-------------------------+-----------+

       mask UNIT...
           Mask one or more units, as specified on the command line. This will
           link these unit files to /dev/null, making it impossible to start
           them. This is a stronger version of disable, since it prohibits all
           kinds of activation of the unit, including enablement and manual
           activation. Use this option with care. This honors the --runtime
           option to only mask temporarily until the next reboot of the
           system. The --now option may be used to ensure that the units are
           also stopped. This command expects valid unit names only, it does
           not accept unit file paths.

       unmask UNIT...
           Unmask one or more unit files, as specified on the command line.
           This will undo the effect of mask. This command expects valid unit
           names only, it does not accept unit file paths.

       link PATH...
           Link a unit file that is not in the unit file search paths into the
           unit file search path. This command expects an absolute path to a
           unit file. The effect of this may be undone with disable. The
           effect of this command is that a unit file is made available for
           commands such as start, even though it is not installed directly in
           the unit search path. The file system where the linked unit files
           are located must be accessible when systemd is started (e.g.
           anything underneath /home or /var is not allowed, unless those
           directories are located on the root file system).

       revert UNIT...
           Revert one or more unit files to their vendor versions. This
           command removes drop-in configuration files that modify the
           specified units, as well as any user-configured unit file that
           overrides a matching vendor supplied unit file. Specifically, for a
           unit "foo.service" the matching directories "foo.service.d/" with
           all their contained files are removed, both below the persistent
           and runtime configuration directories (i.e. below
           /etc/systemd/system and /run/systemd/system); if the unit file has
           a vendor-supplied version (i.e. a unit file located below /usr) any
           matching persistent or runtime unit file that overrides it is
           removed, too. Note that if a unit file has no vendor-supplied
           version (i.e. is only defined below /etc/systemd/system or
           /run/systemd/system, but not in a unit file stored below /usr),
           then it is not removed. Also, if a unit is masked, it is unmasked.

           Effectively, this command may be used to undo all changes made with
           systemctl edit, systemctl set-property and systemctl mask and puts
           the original unit file with its settings back in effect.

       add-wants TARGET UNIT..., add-requires TARGET UNIT...
           Adds "Wants=" or "Requires=" dependencies, respectively, to the
           specified TARGET for one or more units.

           This command honors --system, --user, --runtime and --global in a
           way similar to enable.

       edit UNIT...
           Edit a drop-in snippet or a whole replacement file if --full is
           specified, to extend or override the specified unit.

           Depending on whether --system (the default), --user, or --global is
           specified, this command creates a drop-in file for each unit either
           for the system, for the calling user, or for all futures logins of
           all users. Then, the editor (see the "Environment" section below)
           is invoked on temporary files which will be written to the real
           location if the editor exits successfully.

           If --full is specified, this will copy the original units instead
           of creating drop-in files.

           If --force is specified and any units do not already exist, new
           unit files will be opened for editing.

           If --runtime is specified, the changes will be made temporarily in
           /run and they will be lost on the next reboot.

           If the temporary file is empty upon exit, the modification of the
           related unit is canceled.

           After the units have been edited, systemd configuration is reloaded
           (in a way that is equivalent to daemon-reload).

           Note that this command cannot be used to remotely edit units and
           that you cannot temporarily edit units which are in /etc, since
           they take precedence over /run.

       get-default
           Return the default target to boot into. This returns the target
           unit name default.target is aliased (symlinked) to.

       set-default TARGET
           Set the default target to boot into. This sets (symlinks) the
           default.target alias to the given target unit.

   Machine Commands
       list-machines [PATTERN...]
           List the host and all running local containers with their state. If
           one or more PATTERNs are specified, only containers matching one of
           them are shown.

   Job Commands
       list-jobs [PATTERN...]
           List jobs that are in progress. If one or more PATTERNs are
           specified, only jobs for units matching one of them are shown.

           When combined with --after or --before the list is augmented with
           information on which other job each job is waiting for, and which
           other jobs are waiting for it, see above.

       cancel JOB...
           Cancel one or more jobs specified on the command line by their
           numeric job IDs. If no job ID is specified, cancel all pending
           jobs.

   Environment Commands
       show-environment
           Dump the systemd manager environment block. This is the environment
           block that is passed to all processes the manager spawns. The
           environment block will be dumped in straight-forward form suitable
           for sourcing into most shells. If no special characters or
           whitespace is present in the variable values, no escaping is
           performed, and the assignments have the form "VARIABLE=value". If
           whitespace or characters which have special meaning to the shell
           are present, dollar-single-quote escaping is used, and assignments
           have the form "VARIABLE=$'value'". This syntax is known to be
           supported by bash(1), zsh(1), ksh(1), and busybox(1)'s ash(1), but
           not dash(1) or fish(1).

       set-environment VARIABLE=VALUE...
           Set one or more systemd manager environment variables, as specified
           on the command line.

       unset-environment VARIABLE...
           Unset one or more systemd manager environment variables. If only a
           variable name is specified, it will be removed regardless of its
           value. If a variable and a value are specified, the variable is
           only removed if it has the specified value.

       import-environment [VARIABLE...]
           Import all, one or more environment variables set on the client
           into the systemd manager environment block. If no arguments are
           passed, the entire environment block is imported. Otherwise, a list
           of one or more environment variable names should be passed, whose
           client-side values are then imported into the manager's environment
           block.

   Manager State Commands
       daemon-reload
           Reload the systemd manager configuration. This will rerun all
           generators (see systemd.generator(7)), reload all unit files, and
           recreate the entire dependency tree. While the daemon is being
           reloaded, all sockets systemd listens on behalf of user
           configuration will stay accessible.

           This command should not be confused with the reload command.

       daemon-reexec
           Reexecute the systemd manager. This will serialize the manager
           state, reexecute the process and deserialize the state again. This
           command is of little use except for debugging and package upgrades.
           Sometimes, it might be helpful as a heavy-weight daemon-reload.
           While the daemon is being reexecuted, all sockets systemd listening
           on behalf of user configuration will stay accessible.

       log-level [LEVEL]
           If no argument is given, print the current log level of the
           manager. If an optional argument LEVEL is provided, then the
           command changes the current log level of the manager to LEVEL
           (accepts the same values as --log-level= described in systemd(1)).

       log-target [TARGET]
           If no argument is given, print the current log target of the
           manager. If an optional argument TARGET is provided, then the
           command changes the current log target of the manager to TARGET
           (accepts the same values as --log-target=, described in
           systemd(1)).

       service-watchdogs [yes|no]
           If no argument is given, print the current state of service runtime
           watchdogs of the manager. If an optional boolean argument is
           provided, then globally enables or disables the service runtime
           watchdogs (WatchdogSec=) and emergency actions (e.g.  OnFailure= or
           StartLimitAction=); see systemd.service(5). The hardware watchdog
           is not affected by this setting.

   System Commands
       is-system-running
           Checks whether the system is operational. This returns success
           (exit code 0) when the system is fully up and running, specifically
           not in startup, shutdown or maintenance mode, and with no failed
           services. Failure is returned otherwise (exit code non-zero). In
           addition, the current state is printed in a short string to
           standard output, see the table below. Use --quiet to suppress this
           output.

           Use --wait to wait until the boot process is completed before
           printing the current state and returning the appropriate error
           status. If --wait is in use, states initializing or starting will
           not be reported, instead the command will block until a later state
           (such as running or degraded) is reached.

           Table 2. is-system-running output
           +-------------+---------------------+-----------+
           |Name         | Description         | Exit Code |
           +-------------+---------------------+-----------+
           |initializing | Early bootup,       | > 0       |
           |             | before basic.target |           |
           |             | is reached or the   |           |
           |             | maintenance state   |           |
           |             | entered.            |           |
           +-------------+---------------------+-----------+
           |starting     | Late bootup, before | > 0       |
           |             | the job queue       |           |
           |             | becomes idle for    |           |
           |             | the first time, or  |           |
           |             | one of the rescue   |           |
           |             | targets are         |           |
           |             | reached.            |           |
           +-------------+---------------------+-----------+
           |running      | The system is fully | 0         |
           |             | operational.        |           |
           +-------------+---------------------+-----------+
           |degraded     | The system is       | > 0       |
           |             | operational but one |           |
           |             | or more units       |           |
           |             | failed.             |           |
           +-------------+---------------------+-----------+
           |maintenance  | The rescue or       | > 0       |
           |             | emergency target is |           |
           |             | active.             |           |
           +-------------+---------------------+-----------+
           |stopping     | The manager is      | > 0       |
           |             | shutting down.      |           |
           +-------------+---------------------+-----------+
           |offline      | The manager is not  | > 0       |
           |             | running.            |           |
           |             | Specifically, this  |           |
           |             | is the operational  |           |
           |             | state if an         |           |
           |             | incompatible        |           |
           |             | program is running  |           |
           |             | as system manager   |           |
           |             | (PID 1).            |           |
           +-------------+---------------------+-----------+
           |unknown      | The operational     | > 0       |
           |             | state could not be  |           |
           |             | determined, due to  |           |
           |             | lack of resources   |           |
           |             | or another error    |           |
           |             | cause.              |           |
           +-------------+---------------------+-----------+

       default
           Enter default mode. This is equivalent to systemctl isolate
           default.target. This operation is blocking by default, use
           --no-block to request asynchronous behavior.

       rescue
           Enter rescue mode. This is equivalent to systemctl isolate
           rescue.target. This operation is blocking by default, use
           --no-block to request asynchronous behavior.

       emergency
           Enter emergency mode. This is equivalent to systemctl isolate
           emergency.target. This operation is blocking by default, use
           --no-block to request asynchronous behavior.

       halt
           Shut down and halt the system. This is mostly equivalent to
           systemctl start halt.target --job-mode=replace-irreversibly
           --no-block, but also prints a wall message to all users. This
           command is asynchronous; it will return after the halt operation is
           enqueued, without waiting for it to complete. Note that this
           operation will simply halt the OS kernel after shutting down,
           leaving the hardware powered on. Use systemctl poweroff for
           powering off the system (see below).

           If combined with --force, shutdown of all running services is
           skipped, however all processes are killed and all file systems are
           unmounted or mounted read-only, immediately followed by the system
           halt. If --force is specified twice, the operation is immediately
           executed without terminating any processes or unmounting any file
           systems. This may result in data loss. Note that when --force is
           specified twice the halt operation is executed by systemctl itself,
           and the system manager is not contacted. This means the command
           should succeed even when the system manager has crashed.

       poweroff
           Shut down and power-off the system. This is mostly equivalent to
           systemctl start poweroff.target --job-mode=replace-irreversibly
           --no-block, but also prints a wall message to all users. This
           command is asynchronous; it will return after the power-off
           operation is enqueued, without waiting for it to complete.

           If combined with --force, shutdown of all running services is
           skipped, however all processes are killed and all file systems are
           unmounted or mounted read-only, immediately followed by the
           powering off. If --force is specified twice, the operation is
           immediately executed without terminating any processes or
           unmounting any file systems. This may result in data loss. Note
           that when --force is specified twice the power-off operation is
           executed by systemctl itself, and the system manager is not
           contacted. This means the command should succeed even when the
           system manager has crashed.

       reboot [arg]
           Shut down and reboot the system. This is mostly equivalent to
           systemctl start reboot.target --job-mode=replace-irreversibly
           --no-block, but also prints a wall message to all users. This
           command is asynchronous; it will return after the reboot operation
           is enqueued, without waiting for it to complete.

           If combined with --force, shutdown of all running services is
           skipped, however all processes are killed and all file systems are
           unmounted or mounted read-only, immediately followed by the reboot.
           If --force is specified twice, the operation is immediately
           executed without terminating any processes or unmounting any file
           systems. This may result in data loss. Note that when --force is
           specified twice the reboot operation is executed by systemctl
           itself, and the system manager is not contacted. This means the
           command should succeed even when the system manager has crashed.

           If the optional argument arg is given, it will be passed as the
           optional argument to the reboot(2) system call. The value is
           architecture and firmware specific. As an example, "recovery" might
           be used to trigger system recovery, and "fota" might be used to
           trigger a "firmware over the air" update.

       kexec
           Shut down and reboot the system via kexec. This is equivalent to
           systemctl start kexec.target --job-mode=replace-irreversibly
           --no-block. This command is asynchronous; it will return after the
           reboot operation is enqueued, without waiting for it to complete.

           If combined with --force, shutdown of all running services is
           skipped, however all processes are killed and all file systems are
           unmounted or mounted read-only, immediately followed by the reboot.

       exit [EXIT_CODE]
           Ask the service manager to quit. This is only supported for user
           service managers (i.e. in conjunction with the --user option) or in
           containers and is equivalent to poweroff otherwise. This command is
           asynchronous; it will return after the exit operation is enqueued,
           without waiting for it to complete.

           The service manager will exit with the specified exit code, if
           EXIT_CODE is passed.

       switch-root ROOT [INIT]
           Switches to a different root directory and executes a new system
           manager process below it. This is intended for usage in initial RAM
           disks ("initrd"), and will transition from the initrd's system
           manager process (a.k.a. "init" process) to the main system manager
           process which is loaded from the actual host volume. This call
           takes two arguments: the directory that is to become the new root
           directory, and the path to the new system manager binary below it
           to execute as PID 1. If the latter is omitted or the empty string,
           a systemd binary will automatically be searched for and used as
           init. If the system manager path is omitted, equal to the empty
           string or identical to the path to the systemd binary, the state of
           the initrd's system manager process is passed to the main system
           manager, which allows later introspection of the state of the
           services involved in the initrd boot phase.

       suspend
           Suspend the system. This will trigger activation of the special
           target unit suspend.target. This command is asynchronous, and will
           return after the suspend operation is successfully enqueued. It
           will not wait for the suspend/resume cycle to complete.

       hibernate
           Hibernate the system. This will trigger activation of the special
           target unit hibernate.target. This command is asynchronous, and
           will return after the hibernation operation is successfully
           enqueued. It will not wait for the hibernate/thaw cycle to
           complete.

       hybrid-sleep
           Hibernate and suspend the system. This will trigger activation of
           the special target unit hybrid-sleep.target. This command is
           asynchronous, and will return after the hybrid sleep operation is
           successfully enqueued. It will not wait for the sleep/wake-up cycle
           to complete.

       suspend-then-hibernate
           Suspend the system and hibernate it after the delay specified in
           systemd-sleep.conf. This will trigger activation of the special
           target unit suspend-then-hibernate.target. This command is
           asynchronous, and will return after the hybrid sleep operation is
           successfully enqueued. It will not wait for the sleep/wake-up or
           hibernate/thaw cycle to complete.

   Parameter Syntax
       Unit commands listed above take either a single unit name (designated
       as UNIT), or multiple unit specifications (designated as PATTERN...).
       In the first case, the unit name with or without a suffix must be
       given. If the suffix is not specified (unit name is "abbreviated"),
       systemctl will append a suitable suffix, ".service" by default, and a
       type-specific suffix in case of commands which operate only on specific
       unit types. For example,

           # systemctl start sshd

       and

           # systemctl start sshd.service

       are equivalent, as are

           # systemctl isolate default

       and

           # systemctl isolate default.target

       Note that (absolute) paths to device nodes are automatically converted
       to device unit names, and other (absolute) paths to mount unit names.

           # systemctl status /dev/sda
           # systemctl status /home

       are equivalent to:

           # systemctl status dev-sda.device
           # systemctl status home.mount

       In the second case, shell-style globs will be matched against the
       primary names of all units currently in memory; literal unit names,
       with or without a suffix, will be treated as in the first case. This
       means that literal unit names always refer to exactly one unit, but
       globs may match zero units and this is not considered an error.

       Glob patterns use fnmatch(3), so normal shell-style globbing rules are
       used, and "*", "?", "[]" may be used. See glob(7) for more details. The
       patterns are matched against the primary names of units currently in
       memory, and patterns which do not match anything are silently skipped.
       For example:

           # systemctl stop sshd@*.service

       will stop all sshd@.service instances. Note that alias names of units,
       and units that aren't in memory are not considered for glob expansion.

       For unit file commands, the specified UNIT should be the name of the
       unit file (possibly abbreviated, see above), or the absolute path to
       the unit file:

           # systemctl enable foo.service

       or

           # systemctl link /path/to/foo.service

OPTIONS
       The following options are understood:

       -t, --type=
           The argument should be a comma-separated list of unit types such as
           service and socket.

           If one of the arguments is a unit type, when listing units, limit
           display to certain unit types. Otherwise, units of all types will
           be shown.

           As a special case, if one of the arguments is help, a list of
           allowed values will be printed and the program will exit.

       --state=
           The argument should be a comma-separated list of unit LOAD, SUB, or
           ACTIVE states. When listing units, show only those in the specified
           states. Use --state=failed to show only failed units.

           As a special case, if one of the arguments is help, a list of
           allowed values will be printed and the program will exit.

       -p, --property=
           When showing unit/job/manager properties with the show command,
           limit display to properties specified in the argument. The argument
           should be a comma-separated list of property names, such as
           "MainPID". Unless specified, all known properties are shown. If
           specified more than once, all properties with the specified names
           are shown. Shell completion is implemented for property names.

           For the manager itself, systemctl show will show all available
           properties. Those properties are documented in systemd-
           system.conf(5).

           Properties for units vary by unit type, so showing any unit (even a
           non-existent one) is a way to list properties pertaining to this
           type. Similarly, showing any job will list properties pertaining to
           all jobs. Properties for units are documented in systemd.unit(5),
           and the pages for individual unit types systemd.service(5),
           systemd.socket(5), etc.

       -a, --all
           When listing units with list-units, also show inactive units and
           units which are following other units. When showing
           unit/job/manager properties, show all properties regardless whether
           they are set or not.

           To list all units installed in the file system, use the
           list-unit-files command instead.

           When listing units with list-dependencies, recursively show
           dependencies of all dependent units (by default only dependencies
           of target units are shown).

           When used with status, show journal messages in full, even if they
           include unprintable characters or are very long. By default, fields
           with unprintable characters are abbreviated as "blob data". (Note
           that the pager may escape unprintable characters again.)

       -r, --recursive
           When listing units, also show units of local containers. Units of
           local containers will be prefixed with the container name,
           separated by a single colon character (":").

       --reverse
           Show reverse dependencies between units with list-dependencies,
           i.e. follow dependencies of type WantedBy=, RequiredBy=, PartOf=,
           BoundBy=, instead of Wants= and similar.

       --after
           With list-dependencies, show the units that are ordered before the
           specified unit. In other words, recursively list units following
           the After= dependency.

           Note that any After= dependency is automatically mirrored to create
           a Before= dependency. Temporal dependencies may be specified
           explicitly, but are also created implicitly for units which are
           WantedBy= targets (see systemd.target(5)), and as a result of other
           directives (for example RequiresMountsFor=). Both explicitly and
           implicitly introduced dependencies are shown with
           list-dependencies.

           When passed to the list-jobs command, for each printed job show
           which other jobs are waiting for it. May be combined with --before
           to show both the jobs waiting for each job as well as all jobs each
           job is waiting for.

       --before
           With list-dependencies, show the units that are ordered after the
           specified unit. In other words, recursively list units following
           the Before= dependency.

           When passed to the list-jobs command, for each printed job show
           which other jobs it is waiting for. May be combined with --after to
           show both the jobs waiting for each job as well as all jobs each
           job is waiting for.

       --with-dependencies
           When used with status, cat, list-units, and list-unit-files, those
           commands print all specified units and the dependencies of those
           units.

           Options --reverse, --after, --before may be used to change what
           types of dependencies are shown.

       -l, --full
           Do not ellipsize unit names, process tree entries, journal output,
           or truncate unit descriptions in the output of status, list-units,
           list-jobs, and list-timers.

           Also, show installation targets in the output of is-enabled.

       --value
           When printing properties with show, only print the value, and skip
           the property name and "=".

       --show-types
           When showing sockets, show the type of the socket.

       --job-mode=
           When queuing a new job, this option controls how to deal with
           already queued jobs. It takes one of "fail", "replace",
           "replace-irreversibly", "isolate", "ignore-dependencies",
           "ignore-requirements", "flush", or "triggering". Defaults to
           "replace", except when the isolate command is used which implies
           the "isolate" job mode.

           If "fail" is specified and a requested operation conflicts with a
           pending job (more specifically: causes an already pending start job
           to be reversed into a stop job or vice versa), cause the operation
           to fail.

           If "replace" (the default) is specified, any conflicting pending
           job will be replaced, as necessary.

           If "replace-irreversibly" is specified, operate like "replace", but
           also mark the new jobs as irreversible. This prevents future
           conflicting transactions from replacing these jobs (or even being
           enqueued while the irreversible jobs are still pending).
           Irreversible jobs can still be cancelled using the cancel command.
           This job mode should be used on any transaction which pulls in
           shutdown.target.

           "isolate" is only valid for start operations and causes all other
           units to be stopped when the specified unit is started. This mode
           is always used when the isolate command is used.

           "flush" will cause all queued jobs to be canceled when the new job
           is enqueued.

           If "ignore-dependencies" is specified, then all unit dependencies
           are ignored for this new job and the operation is executed
           immediately. If passed, no required units of the unit passed will
           be pulled in, and no ordering dependencies will be honored. This is
           mostly a debugging and rescue tool for the administrator and should
           not be used by applications.

           "ignore-requirements" is similar to "ignore-dependencies", but only
           causes the requirement dependencies to be ignored, the ordering
           dependencies will still be honored.

           "triggering" may only be used with systemctl stop. In this mode,
           the specified unit and any active units that trigger it are
           stopped. See the discussion of Triggers= in systemd.unit(5) for
           more information about triggering units.

       -T, --show-transaction
           When enqueuing a unit job (for example as effect of a systemctl
           start invocation or similar), show brief information about all jobs
           enqueued, covering both the requested job and any added because of
           unit dependencies. Note that the output will only include jobs
           immediately part of the transaction requested. It is possible that
           service start-up program code run as effect of the enqueued jobs
           might request further jobs to be pulled in. This means that
           completion of the listed jobs might ultimately entail more jobs
           than the listed ones.

       --fail
           Shorthand for --job-mode=fail.

           When used with the kill command, if no units were killed, the
           operation results in an error.

       -i, --ignore-inhibitors
           When system shutdown or a sleep state is requested, ignore
           inhibitor locks. Applications can establish inhibitor locks to
           avoid that certain important operations (such as CD burning or
           suchlike) are interrupted by system shutdown or a sleep state. Any
           user may take these locks and privileged users may override these
           locks. If any locks are taken, shutdown and sleep state requests
           will normally fail (unless privileged) and a list of active locks
           is printed. However, if --ignore-inhibitors is specified, the
           established locks are ignored and not shown, and the operation
           attempted anyway, possibly requiring additional privileges.

       --dry-run
           Just print what would be done. Currently supported by verbs halt,
           poweroff, reboot, kexec, suspend, hibernate, hybrid-sleep,
           suspend-then-hibernate, default, rescue, emergency, and exit.

       -q, --quiet
           Suppress printing of the results of various commands and also the
           hints about truncated log lines. This does not suppress output of
           commands for which the printed output is the only result (like
           show). Errors are always printed.

       --no-block
           Do not synchronously wait for the requested operation to finish. If
           this is not specified, the job will be verified, enqueued and
           systemctl will wait until the unit's start-up is completed. By
           passing this argument, it is only verified and enqueued. This
           option may not be combined with --wait.

       --wait
           Synchronously wait for started units to terminate again. This
           option may not be combined with --no-block. Note that this will
           wait forever if any given unit never terminates (by itself or by
           getting stopped explicitly); particularly services which use
           "RemainAfterExit=yes".

           When used with is-system-running, wait until the boot process is
           completed before returning.

       --user
           Talk to the service manager of the calling user, rather than the
           service manager of the system.

       --system
           Talk to the service manager of the system. This is the implied
           default.

       --failed
           List units in failed state. This is equivalent to --state=failed.

       --no-wall
           Do not send wall message before halt, power-off and reboot.

       --global
           When used with enable and disable, operate on the global user
           configuration directory, thus enabling or disabling a unit file
           globally for all future logins of all users.

       --no-reload
           When used with enable and disable, do not implicitly reload daemon
           configuration after executing the changes.

       --no-ask-password
           When used with start and related commands, disables asking for
           passwords. Background services may require input of a password or
           passphrase string, for example to unlock system hard disks or
           cryptographic certificates. Unless this option is specified and the
           command is invoked from a terminal, systemctl will query the user
           on the terminal for the necessary secrets. Use this option to
           switch this behavior off. In this case, the password must be
           supplied by some other means (for example graphical password
           agents) or the service might fail. This also disables querying the
           user for authentication for privileged operations.

       --kill-who=
           When used with kill, choose which processes to send a signal to.
           Must be one of main, control or all to select whether to kill only
           the main process, the control process or all processes of the unit.
           The main process of the unit is the one that defines the life-time
           of it. A control process of a unit is one that is invoked by the
           manager to induce state changes of it. For example, all processes
           started due to the ExecStartPre=, ExecStop= or ExecReload= settings
           of service units are control processes. Note that there is only one
           control process per unit at a time, as only one state change is
           executed at a time. For services of type Type=forking, the initial
           process started by the manager for ExecStart= is a control process,
           while the process ultimately forked off by that one is then
           considered the main process of the unit (if it can be determined).
           This is different for service units of other types, where the
           process forked off by the manager for ExecStart= is always the main
           process itself. A service unit consists of zero or one main
           process, zero or one control process plus any number of additional
           processes. Not all unit types manage processes of these types
           however. For example, for mount units, control processes are
           defined (which are the invocations of /bin/mount and /bin/umount),
           but no main process is defined. If omitted, defaults to all.

       -s, --signal=
           When used with kill, choose which signal to send to selected
           processes. Must be one of the well-known signal specifiers such as
           SIGTERM, SIGINT or SIGSTOP. If omitted, defaults to SIGTERM.

       --what=
           Select what type of per-unit resources to remove when the clean
           command is invoked, see below. Takes one of configuration, state,
           cache, logs, runtime to select the type of resource. This option
           may be specified more than once, in which case all specified
           resource types are removed. Also accepts the special value all as a
           shortcut for specifying all five resource types. If this option is
           not specified defaults to the combination of cache and runtime,
           i.e. the two kinds of resources that are generally considered to be
           redundant and can be reconstructed on next invocation.

       -f, --force
           When used with enable, overwrite any existing conflicting symlinks.

           When used with edit, create all of the specified units which do not
           already exist.

           When used with halt, poweroff, reboot or kexec, execute the
           selected operation without shutting down all units. However, all
           processes will be killed forcibly and all file systems are
           unmounted or remounted read-only. This is hence a drastic but
           relatively safe option to request an immediate reboot. If --force
           is specified twice for these operations (with the exception of
           kexec), they will be executed immediately, without terminating any
           processes or unmounting any file systems. Warning: specifying
           --force twice with any of these operations might result in data
           loss. Note that when --force is specified twice the selected
           operation is executed by systemctl itself, and the system manager
           is not contacted. This means the command should succeed even when
           the system manager has crashed.

       --message=
           When used with halt, poweroff or reboot, set a short message
           explaining the reason for the operation. The message will be logged
           together with the default shutdown message.

       --now
           When used with enable, the units will also be started. When used
           with disable or mask, the units will also be stopped. The start or
           stop operation is only carried out when the respective enable or
           disable operation has been successful.

       --root=
           When used with enable/disable/is-enabled (and related commands),
           use the specified root path when looking for unit files. If this
           option is present, systemctl will operate on the file system
           directly, instead of communicating with the systemd daemon to carry
           out changes.

       --runtime
           When used with enable, disable, edit, (and related commands), make
           changes only temporarily, so that they are lost on the next reboot.
           This will have the effect that changes are not made in
           subdirectories of /etc but in /run, with identical immediate
           effects, however, since the latter is lost on reboot, the changes
           are lost too.

           Similarly, when used with set-property, make changes only
           temporarily, so that they are lost on the next reboot.

       --preset-mode=
           Takes one of "full" (the default), "enable-only", "disable-only".
           When used with the preset or preset-all commands, controls whether
           units shall be disabled and enabled according to the preset rules,
           or only enabled, or only disabled.

       -n, --lines=
           When used with status, controls the number of journal lines to
           show, counting from the most recent ones. Takes a positive integer
           argument, or 0 to disable journal output. Defaults to 10.

       -o, --output=
           When used with status, controls the formatting of the journal
           entries that are shown. For the available choices, see
           journalctl(1). Defaults to "short".

       --firmware-setup
           When used with the reboot command, indicate to the system's
           firmware to reboot into the firmware setup interface. Note that
           this functionality is not available on all systems.

       --boot-loader-menu=
           When used with the reboot command, indicate to the system's boot
           loader to show the boot loader menu on the following boot. Takes a
           time value as parameter -- indicating the menu time-out. Pass zero
           in order to disable the menu time-out. Note that not all boot
           loaders support this functionality.

       --boot-loader-entry=
           When used with the reboot command, indicate to the system's boot
           loader to boot into a specific boot loader entry on the following
           boot. Takes a boot loader entry identifier as argument, or "help"
           in order to list available entries. Note that not all boot loaders
           support this functionality.

       --plain
           When used with list-dependencies, list-units or list-machines, the
           output is printed as a list instead of a tree, and the bullet
           circles are omitted.

       -H, --host=
           Execute the operation remotely. Specify a hostname, or a username
           and hostname separated by "@", to connect to. The hostname may
           optionally be suffixed by a port ssh is listening on, separated by
           ":", and then a container name, separated by "/", which connects
           directly to a specific container on the specified host. This will
           use SSH to talk to the remote machine manager instance. Container
           names may be enumerated with machinectl -H HOST. Put IPv6 addresses
           in brackets.

       -M, --machine=
           Execute operation on a local container. Specify a container name to
           connect to.

       --no-pager
           Do not pipe output into a pager.

       --no-legend
           Do not print the legend, i.e. column headers and the footer with
           hints.

       -h, --help
           Print a short help text and exit.

       --version
           Print a short version string and exit.

EXIT STATUS
       On success, 0 is returned, a non-zero failure code otherwise.

       systemctl uses the return codes defined by LSB, as defined in LSB
       3.0.0[2].

       Table 3. LSB return codes
       +------+---------------------+---------------------+
       |Value | Description in LSB  | Use in systemd      |
       +------+---------------------+---------------------+
       |0     | "program is running | unit is active      |
       |      | or service is OK"   |                     |
       +------+---------------------+---------------------+
       |1     | "program is dead    | unit not failed     |
       |      | and /var/run pid    | (used by is-failed) |
       |      | file exists"        |                     |
       +------+---------------------+---------------------+
       |2     | "program is dead    | unused              |
       |      | and /var/lock lock  |                     |
       |      | file exists"        |                     |
       +------+---------------------+---------------------+
       |3     | "program is not     | unit is not active  |
       |      | running"            |                     |
       +------+---------------------+---------------------+
       |4     | "program or service | no such unit        |
       |      | status is unknown"  |                     |
       +------+---------------------+---------------------+

       The mapping of LSB service states to systemd unit states is imperfect,
       so it is better to not rely on those return values but to look for
       specific unit states and substates instead.

ENVIRONMENT
       $SYSTEMD_EDITOR
           Editor to use when editing units; overrides $EDITOR and $VISUAL. If
           neither $SYSTEMD_EDITOR nor $EDITOR nor $VISUAL are present or if
           it is set to an empty string or if their execution failed,
           systemctl will try to execute well known editors in this order:
           editor(1), nano(1), vim(1), vi(1).

       $SYSTEMD_PAGER
           Pager to use when --no-pager is not given; overrides $PAGER. If
           neither $SYSTEMD_PAGER nor $PAGER are set, a set of well-known
           pager implementations are tried in turn, including less(1) and
           more(1), until one is found. If no pager implementation is
           discovered no pager is invoked. Setting this environment variable
           to an empty string or the value "cat" is equivalent to passing
           --no-pager.

       $SYSTEMD_LESS
           Override the options passed to less (by default "FRSXMK").

           Users might want to change two options in particular:

           K
               This option instructs the pager to exit immediately when Ctrl+C
               is pressed. To allow less to handle Ctrl+C itself to switch
               back to the pager command prompt, unset this option.

               If the value of $SYSTEMD_LESS does not include "K", and the
               pager that is invoked is less, Ctrl+C will be ignored by the
               executable, and needs to be handled by the pager.

           X
               This option instructs the pager to not send termcap
               initialization and deinitialization strings to the terminal. It
               is set by default to allow command output to remain visible in
               the terminal even after the pager exits. Nevertheless, this
               prevents some pager functionality from working, in particular
               paged output cannot be scrolled with the mouse.

           See less(1) for more discussion.

       $SYSTEMD_LESSCHARSET
           Override the charset passed to less (by default "utf-8", if the
           invoking terminal is determined to be UTF-8 compatible).

       $SYSTEMD_COLORS
           The value must be a boolean. Controls whether colorized output
           should be generated. This can be specified to override the decision
           that systemd makes based on $TERM and what the console is connected
           to.

       $SYSTEMD_URLIFY
           The value must be a boolean. Controls whether clickable links
           should be generated in the output for terminal emulators supporting
           this. This can be specified to override the decision that systemd
           makes based on $TERM and other conditions.

SEE ALSO
       systemd(1), journalctl(1), loginctl(1), machinectl(1), systemd.unit(5),
       systemd.resource-control(5), systemd.special(7), wall(1),
       systemd.preset(5), systemd.generator(7), glob(7)

NOTES
        1. Preset
           https://www.freedesktop.org/wiki/Software/systemd/Preset

        2. LSB 3.0.0
           http://refspecs.linuxbase.org/LSB_3.0.0/LSB-PDA/LSB-PDA/iniscrptact.html

systemd 245                                                       SYSTEMCTL(1)

NAME | SYNOPSIS | DESCRIPTION | COMMANDS | OPTIONS | EXIT STATUS | ENVIRONMENT | SEE ALSO | NOTES