Man page
systemctl

SYSTEMCTL(1)                       systemctl                      SYSTEMCTL(1)

NAME
       systemctl - Control the systemd system and service manager

SYNOPSIS
       systemctl [OPTIONS...] COMMAND [NAME...]

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.

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.

       -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.

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

       -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.

       --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" or "flush". 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.

           "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 honoured.

       --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 (regardless of whether privileged or not) and a
           list of active locks is printed. However, if --ignore-inhibitors is
           specified, the locks are ignored and not printed, and the operation
           attempted anyway, possibly requiring additional privileges.

       -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.

       --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.

       --no-wall
           Do not send wall message before halt, power-off, 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 /usr/bin/mount and
           /usr/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.

       -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 hangs or crashed.

       --message=
           When used with halt, poweroff, reboot or kexec, 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 an alternate root path when looking for unit files.

       --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. 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 boot into setup mode. Note that this is currently only
           supported on some EFI systems and only if the system was booted in
           EFI mode.

       --plain
           When used with list-dependencies, list-units or list-machines, the
           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 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.

       -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.

COMMANDS
       The following commands are understood:

   Unit Commands
       list-units [PATTERN...]
           List units that systemd has loaded. This includes units that are
           either referenced directly or through a dependency, 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.

           This is the default command.

       list-sockets [PATTERN...]
           List socket units 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.

           See also the options --show-types, --all, and --state=.

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

           See also the options --all and --state=.

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

           Note that glob patterns operate on the set of primary names of
           currently loaded units. Units which are not active and are not in a
           failed state usually are not loaded, 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.

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

       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...
           Restart one or more units specified on the command line. If the
           units are not running yet, they will be started.

       try-restart PATTERN...
           Restart 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, restart 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, restart them
           instead. This does nothing if the units are not running.

       isolate NAME
           Start the unit specified on the command line and its dependencies
           and stop all others. 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.

       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.

       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 is
           shown, and if a job ID is specified, properties of the job is
           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.

       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.

       set-property NAME ASSIGNMENT...
           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 instantly, 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 CPUShares=777

           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. Like
           unit file configuration settings, assigning the empty list to list
           parameters will reset the list.

       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 restarted or reset with this
           command.

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

   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 NAME..., 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 diectory, 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.

           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, or only this boot. 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 NAME...
           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 NAME...
           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 commands expects a unit uname only,
           it does not accept paths to unit files.

       preset NAME...
           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.  NAME 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 NAME...
           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.

           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.             |           |
           +------------------+-------------------------+-----------+
           |"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 NAME...
           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 NAME...
           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.

       revert NAME...
           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 peristent 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 NAME..., add-requires TARGET NAME...
           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 NAME...
           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 NAME
           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.

       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. The environment block
           will be dumped in straight-forward form suitable for sourcing into
           a shell script. This environment block will be passed to all
           processes the manager spawns.

       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 Lifecycle 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.

   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.

           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 mostly equivalent to isolate
           default.target.

       rescue
           Enter rescue mode. This is mostly equivalent to isolate
           rescue.target, but also prints a wall message to all users.

       emergency
           Enter emergency mode. This is mostly equivalent to isolate
           emergency.target, but also prints a wall message to all users.

       halt
           Shut down and halt the system. This is mostly equivalent to start
           halt.target --job-mode=replace-irreversibly, but also prints a wall
           message to all users. 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 hangs
           or crashed.

       poweroff
           Shut down and power-off the system. This is mostly equivalent to
           start poweroff.target --job-mode=replace-irreversibly, but also
           prints a wall message to all users. 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 hangs or crashed.

       reboot [arg]
           Shut down and reboot the system. This is mostly equivalent to start
           reboot.target --job-mode=replace-irreversibly, but also prints a
           wall message to all users. 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 hangs or 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 mostly
           equivalent to start kexec.target --job-mode=replace-irreversibly,
           but also prints a wall message to all users. 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 systemd 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.

           The systemd manager can exit with a non-zero exit code if the
           optional argument EXIT_CODE is given.

       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. 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 or equal to the empty string, 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.

       suspend
           Suspend the system. This will trigger activation of the special
           suspend.target target.

       hibernate
           Hibernate the system. This will trigger activation of the special
           hibernate.target target.

       hybrid-sleep
           Hibernate and suspend the system. This will trigger activation of
           the special hybrid-sleep.target target.

   Parameter Syntax
       Unit commands listed above take either a single unit name (designated
       as NAME), 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 currently loaded units; 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 currently loaded
       units, 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 loaded are not considered for glob expansion.

       For unit file commands, the specified NAME 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

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

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.
           Setting this to an empty string or the value "cat" is equivalent to
           passing --no-pager.

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

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
           http://freedesktop.org/wiki/Software/systemd/Preset

systemd 231                                                       SYSTEMCTL(1)



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