SYSTEMCTL(1) systemctl SYSTEMCTL(1)NAME
systemctl, systemd-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:
--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 continously 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-units
List known units.
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 works 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.
status [NAME...|PID...]
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 [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.
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 latter 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 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.
This command honors --system, --user, --global in a similar way as
enable.
is-enabled [NAME...]
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 [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 a preset file. This has the same effect
as disable or enable, depending how the unit is listed in the
preset files.
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 [NAME...]
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 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.
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.
dot
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.
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 [NAME=VALUE...]
Set one or more systemd manager environment variables, as specified
on the command line.
unset-environment [NAME...]
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 start
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 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.
poweroff
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.
reboot
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.
kexec
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.
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.
hibernate
Hibernate the system.
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 ommitted or the empty string,
a systemd binary will automatically be searched for and used as
init. If the system manager path is ommitted 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.
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 ALSOsystemd(1), systemadm(1), journalctl(1), loginctl(1), systemd.unit(5),
systemd.special(7), wall(1)AUTHOR
Lennart Poettering <lennart@poettering.net>
Developer
systemd 02/15/2013 SYSTEMCTL(1)
