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(1) system and
       service manager.

OPTIONS

       The following options are understood:

       -h, --help
           Prints a short help text and exits.

       --version
           Prints a short version string and exits.

       -t, --type=
           The argument should be a comma separated list of unit types such as service and
           socket, or unit load states such as loaded and masked (types and states can be mixed).

           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.

           If one of the arguments is a unit load state, when listing units, limit display to
           certain unit types. Otherwise units of in all load states 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.

       -p, --property=
           When showing unit/job/manager properties with the show command, limit display to
           certain properties as specified as argument. If not specified all set properties are
           shown. The argument should be a comma-separated list of property names, such as
           MainPID. If specified more than once all properties with the specified names are
           shown.

       -a, --all
           When listing units, show all loaded units, regardless of their state, including
           inactive units. When showing unit/job/manager properties, show all properties
           regardless whether they are set or not.

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

       --reverse
           Show reverse dependencies between units with list-dependencies, i.e. units with
           dependencies of type Wants= or Requires= on the given unit.

       --after, --before
           Show which units are started after, resp. before with list-dependencies.

       --failed
           When listing units, show only failed units. Do not confuse with --fail.

       --full
           Do not ellipsize unit names, cgroup members, and truncate unit descriptions in the
           output of list-units and list-jobs.

       --fail
           If the requested operation conflicts with a pending unfinished job, fail the command.
           If this is not specified the requested operation will replace the pending job, if
           necessary. Do not confuse with --failed.

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

       --irreversible
           Mark this transaction's jobs as irreversible. This prevents future conflicting
           transactions from replacing these jobs. The jobs can still be cancelled using the
           cancel command.

       --ignore-dependencies
           When enqueuing a new job ignore all its dependencies and execute it 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.

       -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 if
           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 output to standard output in snapshot, is-active, is-failed, enable and
           disable.

       --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 it is
           completed. By passing this argument it is only verified and enqueued.

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

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

       --system
           Talk to the systemd system manager. (Default)

       --user
           Talk to the systemd manager of the calling user.

       --no-wall
           Don't 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 kill. Must be one of main, control or
           all to select whether to kill only the main process of the unit, the control process
           or all processes of the unit. 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 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, they will be executed immediately without terminating any processes or
           umounting any file systems. Warning: specifying --force twice with any of these
           operations might result in data loss.

       --root=
           When used with enable/disable/is-enabled (and related commands), use alternative root
           path when looking for unit files.

       --runtime
           When used with enable, disable, is-enabled (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.

           Similar, when used with set-cgroup-attr, unset-cgroup-attr, set-cgroup and
           unset-cgroup, make changes only temporarily, so that they are lost on the next reboot.

       -H, --host
           Execute operation remotely. Specify a hostname, or username and hostname separated by
           @, to connect to. This will use SSH to talk to the remote systemd instance.

       -P, --privileged
           Acquire privileges via PolicyKit before executing the operation.

       -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.

       --plain
           When used with list-dependencies the output is printed as a list instead of a tree.

COMMANDS

       The following commands are understood:

       list-units
           List known units (subject to limitations specified with -t).

           This is the default command.

       list-sockets
           List socket units ordered by the listening address. 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
           programatic consumption.

           See also the options --show-types, --all, and --failed.

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

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

       reload NAME...
           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 or load commands.

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

       try-restart NAME...
           Restart one or more units specified on the command line if the units are running. Do
           nothing if units are not running. Note that for compatibility with Red Hat init
           scripts condrestart is equivalent to this command.

       reload-or-restart NAME...
           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.

       reload-or-try-restart NAME...
           Reload one or more units if they support it. If not, restart them instead. Do nothing
           if the units are not running. Note that for compatibility with SysV init scripts
           force-reload is equivalent to this command.

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

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

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

       is-failed NAME...
           Check whether any of the specified units are failed. Returns an exit code 0 if at
           least one is failed, non-zero otherwise. Unless --quiet is specified this will also
           print the current unit state to STDOUT.

       status [NAME...|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 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.

       show [NAME...|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.

       get-cgroup-attr NAME ATTRIBUTE...
           Retrieve the specified control group attributes of the specified unit. Takes a unit
           name and one or more attribute names such as cpu.shares. This will output the current
           values of the specified attributes, separated by new-lines. For attributes that take
           list of items the output will be new-line separated, too. This operation will always
           try to retrieve the data in question from the kernel first, and if that is not
           available use the configured values instead. Instead of low-level control group
           attribute names high-level pretty names may be used, as used for unit execution
           environment configuration, see systemd.exec(5) for details. For example, passing
           memory.limit_in_bytes and MemoryLimit is equivalent.

       set-cgroup-attr NAME ATTRIBUTE VALUE...
           Set the specified control group attribute of the specified unit to the specified
           value. Takes a unit name and an attribute name such as cpu.shares, plus one or more
           values (multiple values may only be used for attributes that take multiple values).
           This operation will immediately update the kernel attribute for this unit and
           persistently store this setting for later reboots (unless --runtime is passed, in
           which case the setting is not saved persistently and only valid until the next
           reboot.) Instead of low-level control group attribute names high-level pretty names
           may be used, as used for unit execution environment configuration, see systemd.exec(5)
           for details. For example, passing memory.limit_in_bytes and MemoryLimit is equivalent.
           This operation will implicitly create a control group for the unit in the controller
           the attribute belongs to, if needed. For attributes that take multiple values, this
           operation will append the specified values to the previously set values list (use
           unset-cgroup-attr to reset the list explicitly). For attributes that take a single
           value only the list will be reset implicitly.

       unset-cgroup-attr NAME ATTRIBUTE...
           Unset the specified control group attributes of the specified unit. Takes a unit name
           and one or more attribut names such as cpu.shares. This operation might or might not
           have an immediate effect on the current kernel attribute value. This will remove any
           persistently stored configuration values for this attribute (as set with
           set-cgroup-attr before), unless --runtime is passed, in which case the configuration
           is reset only until the next reboot. Again, high-level control group attributes may be
           used instead of the low-level kernel ones. For attributes which take multiple values,
           all currently set values are reset.

       set-cgroup NAME CGROUP..., unset-cgroup NAME CGROUP...
           Add or remove a unit to/from a specific control group hierarchy and/or control group
           path. Takes a unit name, plus a control group specification in the syntax
           CONTROLLER:PATH or CONTROLLER. In the latter syntax (where the path is omitted) the
           default unit control group path is implied. Examples: cpu or cpu:/foo/bar. If a unit
           is removed from a control group hierarchy all its processes will be moved to the root
           group of the hierarchy and all control group attributes will be reset. These
           operations are immediately reflected in the kernel hierarchy, and stored persistently
           to disk (unless --runtime is passed).

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

       reset-failed [NAME...]
           Reset the failed state of the specified units, or if no unit name is passed 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-unit-files
           List installed unit files.

       enable NAME...
           Enable one or more unit files or unit file instances, as specified on the command
           line. This will create a number of symlinks as encoded in the [Install] sections of
           the unit files. After the symlinks have been created the systemd configuration is
           reloaded (in a way that is equivalent to daemon-reload) to ensure the changes are
           taken into account immediately. Note that this does not have the effect that any of
           the units enabled are also started at the same time. If this is desired a separate
           start command must be invoked for the unit. Also note that in case of instance
           enablement, symlinks named same as instances are created in install location, however
           they all point to the same template unit file.

           This command will print the actions executed. This output may be suppressed by passing
           --quiet.

           Note that this operation creates only the suggested symlinks for the units. 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 in the 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, to ensure his 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 or --global is specified this enables the unit
           for the system, for the calling user only or for all future logins of all users. Note
           that in the last case no systemd daemon configuration is reloaded.

       disable NAME...
           Disables one or more units. This removes all symlinks to the specified unit files from
           the unit configuration directory, and hence undoes the changes made by enable. Note
           however that this removes all symlinks to the unit files (i.e. including manual
           additions), not just those actually created by enable. This call implicitly reloads
           the systemd daemon configuration after completing the disabling of the units. Note
           that this command does not implicitly stop the units that are being disabled. If this
           is desired an additional stop command should be executed afterwards.

           This command will print the actions executed. This output may be suppressed by passing
           --quiet.

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

       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. To suppress this output use --quiet.

       reenable NAME...
           Reenable one or more unit files, as specified on the command line. This is a
           combination of disable and enable and is useful to reset the symlinks a unit is
           enabled with to the defaults configured in the [Install] section of the unit file.

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

       mask NAME...
           Mask one or more unit files, as specified on the command line. This will link these
           units 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 manual
           activation. Use this option with care.

       unmask NAME...
           Unmask one or more unit files, as specified on the command line. This will undo the
           effect of mask.

       link FILENAME...
           Link a unit file that is not in the unit file search paths into the unit file search
           path. This requires an absolute path to a unit file. The effect of this can be undone
           with disable. The effect of this command is that a unit file is available for start
           and other commands although it isn't installed directly in the unit search path.

       load NAME...
           Load one or more units specified on the command line. This will simply load their
           configuration from disk, but not start them. To start them you need to use the start
           command which will implicitly load a unit that has not been loaded yet. Note that
           systemd garbage collects loaded units that are not active or referenced by an active
           unit. This means that units loaded this way will usually not stay loaded for long.
           Also note that this command cannot be used to reload unit configuration. Use the
           daemon-reload command for that. All in all, this command is of little use except for
           debugging.

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

       list-jobs
           List jobs that are in progress.

       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.

       dump
           Dump server status. This will output a (usually very long) human readable manager
           status dump. Its format is subject to change without notice and should not be parsed
           by applications.

       list-dependencies NAME
           Shows required and wanted units of the specified unit. If no unit is specified
           default.target is implied. Target units are recursively expanded. When --all is passed
           all other units are recursively expanded as well.

       snapshot [NAME]
           Create a snapshot. If a snapshot name is specified, the new snapshot will be named
           after it. If none is specified an automatic snapshot name is generated. In either
           case, the snapshot name used is printed to STDOUT, unless --quiet is specified.

           A snapshot refers to a saved state of the systemd manager. It is implemented itself as
           a unit that is generated dynamically with this command and has dependencies on all
           units active at the time. At a later time the user may return to this state by using
           the isolate command on the snapshot unit.

           Snapshots are only useful for saving and restoring which units are running or are
           stopped, they do not save/restore any other state. Snapshots are dynamic and lost on
           reboot.

       delete NAME...
           Remove a snapshot previously created with snapshot.

       daemon-reload
           Reload systemd manager configuration. This will reload all unit files and recreate the
           entire dependency tree. While the daemon is reloaded, all sockets systemd listens on
           on behalf of user configuration will stay accessible.

           This command should not be confused with the load or reload commands.

       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 reexecuted all sockets systemd listens on on behalf
           of user configuration will stay accessible.

       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.

       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
           --irreversible 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.

       poweroff
           Shut down and power-off the system. This is mostly equivalent to start poweroff.target
           --irreversible 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.

       reboot
           Shut down and reboot the system. This is mostly equivalent to start reboot.target
           --irreversible 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.

       kexec
           Shut down and reboot the system via kexec. This is mostly equivalent to start
           kexec.target --irreversible 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
           Ask the systemd manager to quit. This is only supported for user service managers
           (i.e. in conjunction with the --user option) and will fail otherwise.

       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.

       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. Takes two arguments: the directory to make 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.

EXIT STATUS

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

ENVIRONMENT

       $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.

SEE ALSO

       systemd(1), systemadm(1), journalctl(1), loginctl(1), systemd.unit(5), systemd.special(7),
       wall(1), systemd.preset(5)

NOTES

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