systemctl — Control the systemd system and service manager
systemctl [OPTIONS...] {COMMAND} [NAME...]
systemctl may be used to introspect and control the state of the systemd(1) system and service manager.
The following options are understood:
--help
, -h
Prints a short help text and exits.
--version
Prints a short version string and exits.
--type=
, -t
The argument should
be a unit type name such as
service
and
socket
,
or a unit load state such as
loaded
and
masked
.
If the argument is a unit type, when listing units, limit display to certain unit types. If not specified units of all types will be shown.
If the argument is a unit load state, when listing units, limit display to certain unit types. If not specified units of in all load states will be shown.
--property=
, -p
When showing
unit/job/manager properties, limit
display to certain properties as
specified as argument. If not
specified all set properties are
shown. The argument should be a
property name, such as
MainPID
. If
specified more than once all
properties with the specified names
are shown.
--all
, -a
When listing units, show all units, regardless of their state, including inactive units. When showing unit/job/manager properties, show all properties regardless whether they are set or not.
--failed
When listing units,
show only failed units. Do not confuse
with
--fail
.
--full
Do not ellipsize unit names 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
.
--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 honoured. This is mostly a debugging and rescue tool for the administrator and should not be used by applications.
--quiet
, -q
Suppress output to STDOUT in snapshot, is-active, 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.
--order
, --require
When used in
conjunction with the
dot command (see
below), selects which dependencies are
shown in the dependency graph. If
--order
is passed
only dependencies of type
After=
or
Before=
are
shown. If --require
is passed only dependencies of type
Requires=
,
RequiresOverridable=
,
Requisite=
,
RequisiteOverridable=
,
Wants=
and
Conflicts=
are
shown. If neither is passed, shows
dependencies of all these
types.
--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
.
--signal=
, -s
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
.
--force
, -f
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 dropped 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.
-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.
--lines=
, -n
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.
--follow
, -f
When used with status continuously prints new journal entries as they are appended to the journal.
--output=
, -o
When used with
status controls the
formatting of the journal entries that
are shown. For the available choices
see
journalctl(1). Defaults
to
short
.
The following commands are understood:
List known units.
Start (activate) one or more units specified on the command line.
Stop (deactivate) one or more units specified on the command line.
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 one or more units specified on the command line. If the units are not running yet they will be started.
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 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 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.
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 works only on units
where AllowIsolate=
is
enabled. See
systemd.unit(5)
for details.
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.
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.
Show terse runtime status information about one or more units, followed by its most recent log data from the journal. This function is intended to generate human-readable output. If you are looking for computer-parsable output, use show instead. If a PID is passed information about the unit the process of the PID belongs to is shown.
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.
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 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 installed unit files.
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 latter case no
systemd daemon configuration is
reloaded.
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 is 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
.
Checks whether any of
the specified unit files is 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 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.
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 document.
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 one or more unit files, as specified on the command line. This will undo the effect of mask.
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 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 commands.
List jobs that are in progress.
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 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.
Generate textual
dependency graph description in dot
format for further processing with the
GraphViz
dot(1)
tool. Use a command line like
systemctl dot | dot -Tsvg >
systemd.svg to generate a
graphical dependency tree. Unless
--order
or
--require
is passed
the generated graph will show both
ordering and requirement
dependencies.
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.
Remove a snapshot previously created with snapshot.
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.
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.
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 one or more systemd manager environment variables, as specified on the command line.
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.
Enter default mode. This is mostly equivalent to start default.target.
Enter rescue mode. This is mostly equivalent to isolate rescue.target but also prints a wall message to all users.
Enter emergency mode. This is mostly equivalent to isolate emergency.target but also prints a wall message to all users.
Shut down and halt the
system. This is mostly equivalent to
start halt.target
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 the operation is immediately
executed without terminating any
processes or unmounting any file
systems. This may result in data
loss.
Shut down and
power-off the system. This is mostly
equivalent to start
poweroff.target 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 the operation is
immediately executed without
terminating any processes or
unmounting any file systems. This may
result in data loss.
Shut down and reboot
the system. This is mostly equivalent
to start
reboot.target 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 the operation is immediately
executed without terminating any
processes or unmounting any file
systems. This may result in data
loss.
Shut down and reboot
the system via kexec. This is mostly
equivalent to start
kexec.target 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.
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 the system.
Hibernate the system.
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 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.