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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(1) system and
       service manager.

       For Unit Commands the NAME represents full name of unit.

	   systemctl start foo.service

       For Unit File Commands the NAME represents full name of the unit file, or absolute path to
       the unit file.

	   systemctl start /path/to/foo.service

       While working with services/service files, systemctl is able to append .service suffix
       when it is missing.

	   systemctl start foo

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.

	   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 specified states.

       -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 or before with list-dependencies, respectively.

       -l, --full
	   Do not ellipsize unit names, process tree entries, 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 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 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
	   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 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, (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.

       -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:

   Unit Commands
       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
	   programmatic 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. This
	   does 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. This does
	   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 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 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.

       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

	   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 NAME...|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 [NAME...]
	   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 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.

   Unit File Commands
       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 of also
	   starting any of the units being enabled. If this is desired, a separate start command
	   must be invoked for the unit. Also note that in case of instance enablement, symlinks
	   named the same as instances are created in the 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 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.

       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, --runtime, --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 (see table). To suppress this output, use --quiet.

	   Table 1.  is-enabled output
	   +------------------+--------------------------+--------------+
	   |Printed string    | Meaning 		 | Return value |
	   +------------------+--------------------------+--------------+
	   |"enabled"	      | Enabled through a	 |		|
	   +------------------+ symlink in .wants	 | 0		|
	   |"enabled-runtime" | directory (permanently	 |		|
	   |		      | or just in /run)	 |		|
	   +------------------+--------------------------+--------------+
	   |"linked"	      | Made available through a |		|
	   +------------------+ symlink to the unit file | 1		|
	   |"linked-runtime"  | (permanently or just in  |		|
	   |		      | /run)			 |		|
	   +------------------+--------------------------+--------------+
	   |"masked"	      | Disabled entirely	 |		|
	   +------------------+ (permanently or just in  | 1		|
	   |"masked-runtime"  | /run)			 |		|
	   +------------------+--------------------------+--------------+
	   |"static"	      | Unit is not enabled, but | 0		|
	   |		      | has no provisions for	 |		|
	   |		      | enabling in [Install]	 |		|
	   |		      | section 		 |		|
	   +------------------+--------------------------+--------------+
	   |"disabled"	      | Unit is not enabled	 | 1		|
	   +------------------+--------------------------+--------------+

       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 the
	   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. This honors the --runtime option, to only mask
	   temporarily until the next reoobt of the system.

       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 is not installed directly in the unit search path.

       get-default
	   Get the default target specified via default.target link.

       set-default NAME
	   Set the default target to boot into. Command links default.target to the given unit.

   Job Commands
       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.

   Snapshot Commands
       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.

   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.

   Manager Lifecycle Commands
       daemon-reload
	   Reload systemd manager configuration. This will reload all unit files and recreate the
	   entire dependency tree. While the daemon is being 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 being reexecuted, all sockets systemd listening on
	   behalf of user configuration will stay accessible.

   System Commands
       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. 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.

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.resource-
       management(5), systemd.special(7), wall(1), systemd.preset(5)

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

systemd 208									     SYSTEMCTL(1)
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