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NAME | SYNOPSIS | DESCRIPTION | COMMANDS | OPTIONS | EXIT STATUS | ENVIRONMENT | SEE ALSO | NOTES | COLOPHON |
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SYSTEMCTL(1) systemctl SYSTEMCTL(1)
systemctl - Control the systemd system and service manager
systemctl [OPTIONS...] COMMAND [UNIT...]
systemctl may be used to introspect and control the state of the
"systemd" system and service manager. Please refer to systemd(1)
for an introduction into the basic concepts and functionality
this tool manages.
The following commands are understood:
Unit Commands (Introspection and Modification)
list-units [PATTERN...]
List units that systemd currently has in memory. This
includes units that are either referenced directly or through
a dependency, units that are pinned by applications
programmatically, or units that were active in the past and
have failed. By default only units which are active, have
pending jobs, or have failed are shown; this can be changed
with option --all. If one or more PATTERNs are specified,
only units matching one of them are shown. The units that are
shown are additionally filtered by --type= and --state= if
those options are specified.
Note that this command does not show unit templates, but only
instances of unit templates. Units templates that aren't
instantiated are not runnable, and will thus never show up in
the output of this command. Specifically this means that
[email protected] will never be shown in this list — unless
instantiated, e.g. as [email protected]. Use list-unit-files
(see below) for listing installed unit template files.
Produces output similar to
UNIT LOAD ACTIVE SUB DESCRIPTION
sys-module-fuse.device loaded active plugged /sys/module/fuse
-.mount loaded active mounted Root Mount
boot-efi.mount loaded active mounted /boot/efi
systemd-journald.service loaded active running Journal Service
systemd-logind.service loaded active running Login Service
● [email protected] loaded failed failed User Manager for UID 1000
...
systemd-tmpfiles-clean.timer loaded active waiting Daily Cleanup of Temporary Directories
LOAD = Reflects whether the unit definition was properly loaded.
ACTIVE = The high-level unit activation state, i.e. generalization of SUB.
SUB = The low-level unit activation state, values depend on unit type.
123 loaded units listed. Pass --all to see loaded but inactive units, too.
To show all installed unit files use 'systemctl list-unit-files'.
The header and the last unit of a given type are underlined
if the terminal supports that. A colored dot is shown next to
services which were masked, not found, or otherwise failed.
The LOAD column shows the load state, one of loaded,
not-found, bad-setting, error, masked. The ACTIVE columns
shows the general unit state, one of active, reloading,
inactive, failed, activating, deactivating. The SUB column
shows the unit-type-specific detailed state of the unit,
possible values vary by unit type. The list of possible LOAD,
ACTIVE, and SUB states is not constant and new systemd
releases may both add and remove values.
systemctl --state=help
command may be used to display the current set of possible
values.
This is the default command.
list-automounts [PATTERN...]
List automount units currently in memory, ordered by mount
path. If one or more PATTERNs are specified, only automount
units matching one of them are shown. Produces output similar
to
WHAT WHERE MOUNTED IDLE TIMEOUT UNIT
/dev/sdb1 /mnt/test no 120s mnt-test.automount
binfmt_misc /proc/sys/fs/binfmt_misc yes 0 proc-sys-fs-binfmt_misc.automount
2 automounts listed.
Also see --show-types, --all, and --state=.
Added in version 252.
list-paths [PATTERN...]
List path units currently in memory, ordered by path. If one
or more PATTERNs are specified, only path units matching one
of them are shown. Produces output similar to
PATH CONDITION UNIT ACTIVATES
/run/systemd/ask-password DirectoryNotEmpty systemd-ask-password-plymouth.path systemd-ask-password-plymouth.service
/run/systemd/ask-password DirectoryNotEmpty systemd-ask-password-wall.path systemd-ask-password-wall.service
/var/cache/cups/org.cups.cupsd PathExists cups.path cups.service
3 paths listed.
Also see --show-types, --all, and --state=.
Added in version 254.
list-sockets [PATTERN...]
List socket units currently in memory, ordered by listening
address. If one or more PATTERNs are specified, only socket
units matching one of them are shown. Produces output similar
to
LISTEN UNIT ACTIVATES
/dev/initctl systemd-initctl.socket systemd-initctl.service
...
[::]:22 sshd.socket sshd.service
kobject-uevent 1 systemd-udevd-kernel.socket systemd-udevd.service
5 sockets listed.
Note: because the addresses might contains spaces, this
output is not suitable for programmatic consumption.
Also see --show-types, --all, and --state=.
Added in version 202.
list-timers [PATTERN...]
List timer units currently in memory, ordered by the time
they elapse next. If one or more PATTERNs are specified, only
units matching one of them are shown. Produces output similar
to
NEXT LEFT LAST PASSED UNIT ACTIVATES
- - Thu 2017-02-23 13:40:29 EST 3 days ago ureadahead-stop.timer ureadahead-stop.service
Sun 2017-02-26 18:55:42 EST 1min 14s left Thu 2017-02-23 13:54:44 EST 3 days ago systemd-tmpfiles-clean.timer systemd-tmpfiles-clean.service
Sun 2017-02-26 20:37:16 EST 1h 42min left Sun 2017-02-26 11:56:36 EST 6h ago apt-daily.timer apt-daily.service
Sun 2017-02-26 20:57:49 EST 2h 3min left Sun 2017-02-26 11:56:36 EST 6h ago snapd.refresh.timer snapd.refresh.service
NEXT shows the next time the timer will run.
LEFT shows how long till the next time the timer runs.
LAST shows the last time the timer ran.
PASSED shows how long has passed since the timer last ran.
UNIT shows the name of the timer
ACTIVATES shows the name the service the timer activates when
it runs.
Also see --all and --state=.
Added in version 209.
is-active PATTERN...
Check whether any of the specified units are active (i.e.
running). Returns an exit code 0 if at least one is active,
or non-zero otherwise. Unless --quiet is specified, this will
also print the current unit state to standard output.
is-failed [PATTERN...]
Check whether any of the specified units is in the "failed"
state. If no unit is specified, check whether there are any
failed units, which corresponds to the "degraded" state
returned by is-system-running. 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 or system
state to standard output.
Added in version 197.
status [PATTERN...|PID...]]
Show runtime status information about the whole system or
about one or more units followed by most recent log data from
the journal. If no positional arguments are specified, and no
unit filter is given with --type=, --state=, or --failed,
shows the status of the whole system. If combined with --all,
follows that with the status of all units. If positional
arguments are specified, each positional argument is treated
as either a unit name to show, or a glob pattern to show
units whose names match that pattern, or a PID to show the
unit containing that PID. When --type=, --state=, or --failed
are used, units are additionally filtered by the TYPE and
ACTIVE state.
This function is intended to generate human-readable output.
If you are looking for computer-parsable output, use show
instead. By default, this function only shows 10 lines of
output and ellipsizes lines to fit in the terminal window.
This can be changed with --lines and --full, see above. In
addition, journalctl --unit=NAME or journalctl
--user-unit=NAME use a similar filter for messages and might
be more convenient.
Note that this operation only displays runtime status, i.e.
information about the current invocation of the unit (if it
is running) or the most recent invocation (if it is not
running anymore, and has not been released from memory).
Information about earlier invocations, invocations from
previous system boots, or prior invocations that have already
been released from memory may be retrieved via journalctl
--unit=.
systemd implicitly loads units as necessary, so just running
the status will attempt to load a file. The command is thus
not useful for determining if something was already loaded or
not. The units may possibly also be quickly unloaded after
the operation is completed if there's no reason to keep it in
memory thereafter.
Example 1. Example output from systemctl status
$ systemctl status bluetooth
● bluetooth.service - Bluetooth service
Loaded: loaded (/usr/lib/systemd/system/bluetooth.service; enabled; preset: enabled)
Active: active (running) since Wed 2017-01-04 13:54:04 EST; 1 weeks 0 days ago
Docs: man:bluetoothd(8)
Main PID: 930 (bluetoothd)
Status: "Running"
Tasks: 1
Memory: 648.0K
CPU: 435ms
CGroup: /system.slice/bluetooth.service
└─930 /usr/lib/bluetooth/bluetoothd
Jan 12 10:46:45 example.com bluetoothd[8900]: Not enough free handles to register service
Jan 12 10:46:45 example.com bluetoothd[8900]: Current Time Service could not be registered
Jan 12 10:46:45 example.com bluetoothd[8900]: gatt-time-server: Input/output error (5)
The dot ("●") uses color on supported terminals to summarize
the unit state at a glance. Along with its color, its shape
varies according to its state: "inactive" or "maintenance" is
a white circle ("○"), "active" is a green dot ("●"),
"deactivating" is a white dot, "failed" or "error" is a red
cross ("×"), and "reloading" is a green clockwise circle
arrow ("↻").
The "Loaded:" line in the output will show "loaded" if the
unit has been loaded into memory. Other possible values for
"Loaded:" include: "error" if there was a problem loading it,
"not-found" if no unit file was found for this unit,
"bad-setting" if an essential unit file setting could not be
parsed and "masked" if the unit file has been masked. Along
with showing the path to the unit file, this line will also
show the enablement state. Enabled units are included in the
dependency network between units, and thus are started at
boot or via some other form of activation. See the full table
of possible enablement states — including the definition of
"masked" — in the documentation for the is-enabled command.
The "Active:" line shows active state. The value is usually
"active" or "inactive". Active could mean started, bound,
plugged in, etc depending on the unit type. The unit could
also be in process of changing states, reporting a state of
"activating" or "deactivating". A special "failed" state is
entered when the service failed in some way, such as a crash,
exiting with an error code or timing out. If the failed state
is entered the cause will be logged for later reference.
show [PATTERN...|JOB...]
Show properties of one or more units, jobs, or the manager
itself. If no argument is specified, properties of the
manager will be shown. If a unit name is specified,
properties of the unit are shown, and if a job ID is
specified, properties of the job are 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.
Many properties shown by systemctl show map directly to
configuration settings of the system and service manager and
its unit files. Note that the properties shown by the command
are generally more low-level, normalized versions of the
original configuration settings and expose runtime state in
addition to configuration. For example, properties shown for
service units include the service's current main process
identifier as "MainPID" (which is runtime state), and time
settings are always exposed as properties ending in the
"...USec" suffix even if a matching configuration options end
in "...Sec", because microseconds is the normalized time unit
used internally by the system and service manager.
For details about many of these properties, see the
documentation of the D-Bus interface backing these
properties, see org.freedesktop.systemd1(5).
cat PATTERN...
Show backing files of one or more units. Prints the
"fragment" and "drop-ins" (source files) of units. Each file
is preceded by a comment which includes the file name. Note
that this shows the contents of the backing files on disk,
which might not match the system manager's understanding of
these units if any unit files were updated on disk and the
daemon-reload command wasn't issued since.
Added in version 209.
help PATTERN...|PID...
Show manual pages for one or more units, if available. If a
PID is given, the manual pages for the unit the process
belongs to are shown.
Added in version 185.
list-dependencies [UNIT...]
Shows units required and wanted by the specified units. This
recursively lists units following the Requires=, Requisite=,
Wants=, ConsistsOf=, BindsTo=, and Upholds= dependencies. If
no units are specified, default.target is implied.
The units that are shown are additionally filtered by --type=
and --state= if those options are specified. Note that we
won't be able to use a tree structure in this case, so
--plain is implied.
By default, only target units are recursively expanded. When
--all is passed, all other units are recursively expanded as
well.
Options --reverse, --after, --before may be used to change
what types of dependencies are shown.
Note that this command only lists units currently loaded into
memory by the service manager. In particular, this command is
not suitable to get a comprehensive list at all reverse
dependencies on a specific unit, as it won't list the
dependencies declared by units currently not loaded.
Added in version 198.
start PATTERN...
Start (activate) one or more units specified on the command
line.
Note that unit glob patterns expand to names of units
currently in memory. Units which are not active and are not
in a failed state usually are not in memory, and will not be
matched by any pattern. In addition, in case of instantiated
units, systemd is often unaware of the instance name until
the instance has been started. Therefore, using glob patterns
with start has limited usefulness. Also, secondary alias
names of units are not considered.
Option --all may be used to also operate on inactive units
which are referenced by other loaded units. Note that this is
not the same as operating on "all" possible units, because as
the previous paragraph describes, such a list is ill-defined.
Nevertheless, systemctl start --all GLOB may be useful if all
the units that should match the pattern are pulled in by some
target which is known to be loaded.
stop PATTERN...
Stop (deactivate) one or more units specified on the command
line.
This command will fail if the unit does not exist or if
stopping of the unit is prohibited (see RefuseManualStop= in
systemd.unit(5)). It will not fail if any of the commands
configured to stop the unit (ExecStop=, etc.) fail, because
the manager will still forcibly terminate the unit.
If a unit that gets stopped can still be triggered by other
units, a warning containing the names of the triggering units
is shown. --no-warn can be used to suppress the warning.
reload PATTERN...
Asks all units listed on the command line to reload their
configuration. Note that this will reload the
service-specific configuration, not the unit configuration
file of systemd. If you want systemd to reload the
configuration file of a unit, use the daemon-reload command.
In other words: for the example case of Apache, this will
reload Apache's httpd.conf in the web server, not the
apache.service systemd unit file.
This command should not be confused with the daemon-reload
command.
restart PATTERN...
Stop and then start one or more units specified on the
command line. If the units are not running yet, they will be
started.
Note that restarting a unit with this command does not
necessarily flush out all of the unit's resources before it
is started again. For example, the per-service file
descriptor storage facility (see FileDescriptorStoreMax= in
systemd.service(5)) will remain intact as long as the unit
has a job pending, and is only cleared when the unit is fully
stopped and no jobs are pending anymore. If it is intended
that the file descriptor store is flushed out, too, during a
restart operation an explicit systemctl stop command followed
by systemctl start should be issued.
try-restart PATTERN...
Stop and then start one or more units specified on the
command line if the units are running. This does nothing if
units are not running.
reload-or-restart PATTERN...
Reload one or more units if they support it. If not, stop and
then start them instead. If the units are not running yet,
they will be started.
try-reload-or-restart PATTERN...
Reload one or more units if they support it. If not, stop and
then start them instead. This does nothing if the units are
not running.
Added in version 229.
isolate UNIT
Start the unit specified on the command line and its
dependencies and stop all others, unless they have
IgnoreOnIsolate=yes (see systemd.unit(5)). If a unit name
with no extension is given, an extension of ".target" will be
assumed.
This command is dangerous, since it will immediately stop
processes that are not enabled in the new target, possibly
including the graphical environment or terminal you are
currently using.
Note that this operation is allowed only on units where
AllowIsolate= is enabled. See systemd.unit(5) for details.
kill PATTERN...
Send a UNIX process signal to one or more processes of the
unit. Use --kill-whom= to select which process to send the
signal to. Use --signal= to select the signal to send.
Combine with --kill-value= to enqueue a POSIX Realtime Signal
with an associated value.
clean PATTERN...
Remove the configuration, state, cache, logs or runtime data
of the specified units. Use --what= to select which kind of
resource to remove. For service units this may be used to
remove the directories configured with
ConfigurationDirectory=, StateDirectory=, CacheDirectory=,
LogsDirectory= and RuntimeDirectory=, see systemd.exec(5) for
details. It may also be used to clear the file descriptor
store as enabled via FileDescriptorStoreMax=, see
systemd.service(5) for details. For timer units this may be
used to clear out the persistent timestamp data if
Persistent= is used and --what=state is selected, see
systemd.timer(5). This command only applies to units that use
either of these settings. If --what= is not specified, the
cache and runtime data as well as the file descriptor store
are removed (as these three types of resources are generally
redundant and reproducible on the next invocation of the
unit). Note that the specified units must be stopped to
invoke this operation.
Table 1. Possible values for --what=
┌─────────────────┬──────────────────────────────┐
│ Value │ Unit Setting │
├─────────────────┼──────────────────────────────┤
│ "runtime" │ RuntimeDirectory= │
├─────────────────┼──────────────────────────────┤
│ "state" │ StateDirectory= │
├─────────────────┼──────────────────────────────┤
│ "cache" │ CacheDirectory= │
├─────────────────┼──────────────────────────────┤
│ "logs" │ LogsDirectory= │
├─────────────────┼──────────────────────────────┤
│ "configuration" │ ConfigurationDirectory= │
├─────────────────┼──────────────────────────────┤
│ "fdstore" │ FileDescriptorStorePreserve= │
├─────────────────┼──────────────────────────────┤
│ "all" │ All of the above │
└─────────────────┴──────────────────────────────┘
Added in version 243.
freeze PATTERN...
Freeze one or more units specified on the command line using
cgroup freezer
Freezing the unit will cause all processes contained within
the cgroup corresponding to the unit to be suspended. Being
suspended means that unit's processes won't be scheduled to
run on CPU until thawed. Note that this command is supported
only on systems that use unified cgroup hierarchy. Unit is
automatically thawed just before we execute a job against the
unit, e.g. before the unit is stopped.
Added in version 246.
thaw PATTERN...
Thaw (unfreeze) one or more units specified on the command
line.
This is the inverse operation to the freeze command and
resumes the execution of processes in the unit's cgroup.
Added in version 246.
set-property UNIT PROPERTY=VALUE...
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
immediately, 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 CPUWeight=200
If the specified unit appears to be inactive, the changes
will be only stored on disk as described previously hence
they will be effective when the unit will be started.
Note that this command allows changing multiple properties at
the same time, which is preferable over setting them
individually.
Example: systemctl set-property foobar.service CPUWeight=200
MemoryMax=2G IPAccounting=yes
Like with unit file configuration settings, assigning an
empty setting usually resets a property to its defaults.
Example: systemctl set-property avahi-daemon.service
IPAddressDeny=
Added in version 206.
bind UNIT PATH [PATH]
Bind-mounts a file or directory from the host into the
specified unit's mount namespace. The first path argument is
the source file or directory on the host, the second path
argument is the destination file or directory in the unit's
mount namespace. When the latter is omitted, the destination
path in the unit's mount namespace is the same as the source
path on the host. When combined with the --read-only switch,
a ready-only bind mount is created. When combined with the
--mkdir switch, the destination path is first created before
the mount is applied.
Note that this option is currently only supported for units
that run within a mount namespace (e.g.: with RootImage=,
PrivateMounts=, etc.). This command supports bind-mounting
directories, regular files, device nodes, AF_UNIX socket
nodes, as well as FIFOs. The bind mount is ephemeral, and it
is undone as soon as the current unit process exists. Note
that the namespace mentioned here, where the bind mount will
be added to, is the one where the main service process runs.
Other processes (those exececuted by ExecReload=,
ExecStartPre=, etc.) run in distinct namespaces.
If supported by the kernel, any prior mount on the selected
target will be replaced by the new mount. If not supported,
any prior mount will be over-mounted, but remain pinned and
inaccessible.
Added in version 248.
mount-image UNIT IMAGE [PATH [PARTITION_NAME:MOUNT_OPTIONS]]
Mounts an image from the host into the specified unit's mount
namespace. The first path argument is the source image on the
host, the second path argument is the destination directory
in the unit's mount namespace (i.e. inside
RootImage=/RootDirectory=). The following argument, if any,
is interpreted as a colon-separated tuple of partition name
and comma-separated list of mount options for that partition.
The format is the same as the service MountImages= setting.
When combined with the --read-only switch, a ready-only mount
is created. When combined with the --mkdir switch, the
destination path is first created before the mount is
applied.
Note that this option is currently only supported for units
that run within a mount namespace (i.e. with RootImage=,
PrivateMounts=, etc.). Note that the namespace mentioned here
where the image mount will be added to, is the one where the
main service process runs. Note that the namespace mentioned
here, where the bind mount will be added to, is the one where
the main service process runs. Other processes (those
exececuted by ExecReload=, ExecStartPre=, etc.) run in
distinct namespaces.
If supported by the kernel, any prior mount on the selected
target will be replaced by the new mount. If not supported,
any prior mount will be over-mounted, but remain pinned and
inaccessible.
Example:
systemctl mount-image foo.service /tmp/img.raw /var/lib/image root:ro,nosuid
systemctl mount-image --mkdir bar.service /tmp/img.raw /var/lib/baz/img
Added in version 248.
service-log-level SERVICE [LEVEL]
If the LEVEL argument is not given, print the current log
level as reported by service SERVICE.
If the optional argument LEVEL is provided, then change the
current log level of the service to LEVEL. The log level
should be a typical syslog log level, i.e. a value in the
range 0...7 or one of the strings emerg, alert, crit, err,
warning, notice, info, debug; see syslog(3) for details.
The service must have the appropriate BusName=destination
property and also implement the generic
org.freedesktop.LogControl1(5) interface. (systemctl will use
the generic D-Bus protocol to access the
org.freedesktop.LogControl1.LogLevel interface for the D-Bus
name destination.)
Added in version 247.
service-log-target SERVICE [TARGET]
If the TARGET argument is not given, print the current log
target as reported by service SERVICE.
If the optional argument TARGET is provided, then change the
current log target of the service to TARGET. The log target
should be one of the strings console (for log output to the
service's standard error stream), kmsg (for log output to the
kernel log buffer), journal (for log output to
systemd-journald.service(8) using the native journal
protocol), syslog (for log output to the classic syslog
socket /dev/log), null (for no log output whatsoever) or auto
(for an automatically determined choice, typically equivalent
to console if the service is invoked interactively, and
journal or syslog otherwise).
For most services, only a small subset of log targets make
sense. In particular, most "normal" services should only
implement console, journal, and null. Anything else is only
appropriate for low-level services that are active in very
early boot before proper logging is established.
The service must have the appropriate BusName=destination
property and also implement the generic
org.freedesktop.LogControl1(5) interface. (systemctl will use
the generic D-Bus protocol to access the
org.freedesktop.LogControl1.LogLevel interface for the D-Bus
name destination.)
Added in version 247.
reset-failed [PATTERN...]
Reset the "failed" state of the specified units, or if no
unit name is passed, reset the state of all units. When a
unit fails in some way (i.e. process exiting with non-zero
error code, terminating abnormally or timing out), it will
automatically enter the "failed" state and its exit code and
status is recorded for introspection by the administrator
until the service is stopped/re-started or reset with this
command.
In addition to resetting the "failed" state of a unit it also
resets various other per-unit properties: the start rate
limit counter of all unit types is reset to zero, as is the
restart counter of service units. Thus, if a unit's start
limit (as configured with
StartLimitIntervalSec=/StartLimitBurst=) is hit and the unit
refuses to be started again, use this command to make it
startable again.
whoami [PID...]
Returns the units the processes referenced by the given PIDs
belong to (one per line). If no PID is specified returns the
unit the systemctl command is invoked in.
Added in version 254.
Unit File Commands
list-unit-files [PATTERN...]
List unit files installed on the system, in combination with
their enablement state (as reported by is-enabled). If one or
more PATTERNs are specified, only unit files whose name
matches one of them are shown (patterns matching unit file
system paths are not supported).
Unlike list-units this command will list template units in
addition to explicitly instantiated units.
Added in version 233.
enable UNIT..., enable PATH...
Enable one or more units or unit instances. This will create
a set of symlinks, as encoded in the [Install] sections of
the indicated unit files. After the symlinks have been
created, the system manager configuration is reloaded (in a
way equivalent to daemon-reload), in order to ensure the
changes are taken into account immediately. Note that this
does not have the effect of also starting any of the units
being enabled. If this is desired, combine this command with
the --now switch, or invoke start with appropriate arguments
later. Note that in case of unit instance enablement (i.e.
enablement of units of the form [email protected]), symlinks
named the same as instances are created in the unit
configuration directory, however they point to the single
template unit file they are instantiated from.
This command expects either valid unit names (in which case
various unit file directories are automatically searched for
unit files with appropriate names), or absolute paths to unit
files (in which case these files are read directly). If a
specified unit file is located outside of the usual unit file
directories, an additional symlink is created, linking it
into the unit configuration path, thus ensuring it is found
when requested by commands such as start. The file system
where the linked unit files are located must be accessible
when systemd is started (e.g. anything underneath /home/ or
/var/ is not allowed, unless those directories are located on
the root file system).
This command will print the file system operations executed.
This output may be suppressed by passing --quiet.
Note that this operation creates only the symlinks suggested
in the [Install] section of the unit files. While this
command is the recommended way to manipulate the unit
configuration directory, the administrator is free to make
additional changes manually by placing or removing symlinks
below this directory. This is particularly useful to create
configurations that deviate from the suggested default
installation. In this case, the administrator must make sure
to invoke daemon-reload manually as necessary, in order to
ensure the changes are taken into account.
When using this operation on units without install
information, a warning about it is shown. --no-warn can be
used to suppress the warning.
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. Note that in the last case,
no systemd daemon configuration is reloaded.
Using enable on masked units is not supported and results in
an error.
disable UNIT...
Disables one or more units. This removes all symlinks to the
unit files backing the specified units from the unit
configuration directory, and hence undoes any changes made by
enable or link. Note that this removes all symlinks to
matching unit files, including manually created symlinks, and
not just those actually created by enable or link. Note that
while disable undoes the effect of enable, the two commands
are otherwise not symmetric, as disable may remove more
symlinks than a prior enable invocation of the same unit
created.
This command expects valid unit names only, it does not
accept paths to unit files.
In addition to the units specified as arguments, all units
are disabled that are listed in the Also= setting contained
in the [Install] section of any of the unit files being
operated on.
This command implicitly reloads the system manager
configuration after completing the operation. Note that this
command does not implicitly stop the units that are being
disabled. If this is desired, either combine this command
with the --now switch, or invoke the stop command with
appropriate arguments later.
This command will print information about the file system
operations (symlink removals) executed. This output may be
suppressed by passing --quiet.
If a unit gets disabled but its triggering units are still
active, a warning containing the names of the triggering
units is shown. --no-warn can be used to suppress the
warning.
When this command is used with --user, the units being
operated on might still be enabled in global scope, and thus
get started automatically even after a successful disablement
in user scope. In this case, a warning about it is shown,
which can be suppressed using --no-warn.
This command honors --system, --user, --runtime, --global and
--no-warn in a similar way as enable.
Added in version 238.
reenable UNIT...
Reenable one or more units, as specified on the command line.
This is a combination of disable and enable and is useful to
reset the symlinks a unit file is enabled with to the
defaults configured in its [Install] section. This command
expects a unit name only, it does not accept paths to unit
files.
Added in version 238.
preset UNIT...
Reset the enable/disable status one or more unit files, as
specified on the command line, to the defaults configured in
the preset policy files. This has the same effect as disable
or enable, depending how the unit is listed in the preset
files.
Use --preset-mode= to control whether units shall be enabled
and disabled, or only enabled, or only disabled.
If the unit carries no install information, it will be
silently ignored by this command. UNIT must be the real unit
name, any alias names are ignored silently.
For more information on the preset policy format, see
systemd.preset(5).
Added in version 238.
preset-all
Resets all installed unit files to the defaults configured in
the preset policy file (see above).
Use --preset-mode= to control whether units shall be enabled
and disabled, or only enabled, or only disabled.
Added in version 215.
is-enabled UNIT...
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. To
show installation targets, use --full.
Table 2. is-enabled output
┌───────────────────┬─────────────────────────┬───────────┐
│ Name │ Description │ Exit Code │
├───────────────────┼─────────────────────────┼───────────┤
│ "enabled" │ Enabled via │ │
├───────────────────┤ .wants/, │ │
│ "enabled-runtime" │ .requires/ or │ │
│ │ Alias= symlinks │ 0 │
│ │ (permanently in │ │
│ │ /etc/systemd/system/, │ │
│ │ or transiently in │ │
│ │ /run/systemd/system/). │ │
├───────────────────┼─────────────────────────┼───────────┤
│ "linked" │ Made available through │ │
├───────────────────┤ one or more symlinks │ │
│ "linked-runtime" │ to the unit file │ │
│ │ (permanently in │ │
│ │ /etc/systemd/system/ │ │
│ │ or transiently in │ > 0 │
│ │ /run/systemd/system/), │ │
│ │ even though the unit │ │
│ │ file might reside │ │
│ │ outside of the unit │ │
│ │ file search path. │ │
├───────────────────┼─────────────────────────┼───────────┤
│ "alias" │ The name is an alias │ 0 │
│ │ (symlink to another │ │
│ │ unit file). │ │
├───────────────────┼─────────────────────────┼───────────┤
│ "masked" │ Completely disabled, │ │
├───────────────────┤ so that any start │ │
│ "masked-runtime" │ operation on it fails │ │
│ │ (permanently in │ > 0 │
│ │ /etc/systemd/system/ │ │
│ │ or transiently in │ │
│ │ /run/systemd/systemd/). │ │
├───────────────────┼─────────────────────────┼───────────┤
│ "static" │ The unit file is not │ 0 │
│ │ enabled, and has no │ │
│ │ provisions for enabling │ │
│ │ in the [Install] unit │ │
│ │ file section. │ │
├───────────────────┼─────────────────────────┼───────────┤
│ "indirect" │ The unit file itself is │ 0 │
│ │ not enabled, but it has │ │
│ │ a non-empty Also= │ │
│ │ setting in the │ │
│ │ [Install] unit file │ │
│ │ section, listing other │ │
│ │ unit files that might │ │
│ │ be enabled, or it has │ │
│ │ an alias under a │ │
│ │ different name through │ │
│ │ a symlink that is not │ │
│ │ specified in Also=. For │ │
│ │ template unit files, an │ │
│ │ instance different than │ │
│ │ the one specified in │ │
│ │ DefaultInstance= is │ │
│ │ enabled. │ │
├───────────────────┼─────────────────────────┼───────────┤
│ "disabled" │ The unit file is not │ > 0 │
│ │ enabled, but contains │ │
│ │ an [Install] section │ │
│ │ with installation │ │
│ │ instructions. │ │
├───────────────────┼─────────────────────────┼───────────┤
│ "generated" │ The unit file was │ 0 │
│ │ generated dynamically │ │
│ │ via a generator tool. │ │
│ │ See │ │
│ │ systemd.generator(7). │ │
│ │ Generated unit files │ │
│ │ may not be enabled, │ │
│ │ they are enabled │ │
│ │ implicitly by their │ │
│ │ generator. │ │
├───────────────────┼─────────────────────────┼───────────┤
│ "transient" │ The unit file has been │ 0 │
│ │ created dynamically │ │
│ │ with the runtime API. │ │
│ │ Transient units may not │ │
│ │ be enabled. │ │
├───────────────────┼─────────────────────────┼───────────┤
│ "bad" │ The unit file is │ > 0 │
│ │ invalid or another │ │
│ │ error occurred. Note │ │
│ │ that is-enabled will │ │
│ │ not actually return │ │
│ │ this state, but print │ │
│ │ an error message │ │
│ │ instead. However the │ │
│ │ unit file listing │ │
│ │ printed by │ │
│ │ list-unit-files might │ │
│ │ show it. │ │
├───────────────────┼─────────────────────────┼───────────┤
│ "not-found" │ The unit file doesn't │ 4 │
│ │ exist. │ │
└───────────────────┴─────────────────────────┴───────────┘
Added in version 238.
mask UNIT...
Mask one or more units, as specified on the command line.
This will link these unit files to /dev/null, making it
impossible to start them. This is a stronger version of
disable, since it prohibits all kinds of activation of the
unit, including enablement and manual activation. Use this
option with care. This honors the --runtime option to only
mask temporarily until the next reboot of the system. The
--now option may be used to ensure that the units are also
stopped. This command expects valid unit names only, it does
not accept unit file paths.
Note that this will create a symlink under the unit's name in
/etc/systemd/system/ (in case --runtime is not specified) or
/run/systemd/system/ (in case --runtime is specified). If a
matching unit file already exists under these directories
this operation will hence fail. This means that the operation
is primarily useful to mask units shipped by the vendor (as
those are shipped in /usr/lib/systemd/system/ and not the
aforementioned two directories), but typically doesn't work
for units created locally (as those are typically placed
precisely in the two aforementioned directories). Similar
restrictions apply for --user mode, in which case the
directories are below the user's home directory however.
If a unit gets masked but its triggering units are still
active, a warning containing the names of the triggering
units is shown. --no-warn can be used to suppress the
warning.
Added in version 238.
unmask UNIT...
Unmask one or more unit files, as specified on the command
line. This will undo the effect of mask. This command expects
valid unit names only, it does not accept unit file paths.
Added in version 238.
link PATH...
Link a unit file that is not in the unit file search path
into the unit file search path. This command expects an
absolute path to a unit file. The effect of this may be
undone with disable. The effect of this command is that a
unit file is made available for commands such as start, even
though it is not installed directly in the unit search path.
The file system where the linked unit files are located must
be accessible when systemd is started (e.g. anything
underneath /home/ or /var/ is not allowed, unless those
directories are located on the root file system).
Added in version 233.
revert UNIT...
Revert one or more unit files to their vendor versions. This
command removes drop-in configuration files that modify the
specified units, as well as any user-configured unit file
that overrides a matching vendor supplied unit file.
Specifically, for a unit "foo.service" the matching
directories "foo.service.d/" with all their contained files
are removed, both below the persistent and runtime
configuration directories (i.e. below /etc/systemd/system and
/run/systemd/system); if the unit file has a vendor-supplied
version (i.e. a unit file located below /usr/) any matching
persistent or runtime unit file that overrides it is removed,
too. Note that if a unit file has no vendor-supplied version
(i.e. is only defined below /etc/systemd/system or
/run/systemd/system, but not in a unit file stored below
/usr/), then it is not removed. Also, if a unit is masked, it
is unmasked.
Effectively, this command may be used to undo all changes
made with systemctl edit, systemctl set-property and
systemctl mask and puts the original unit file with its
settings back in effect.
Added in version 230.
add-wants TARGET UNIT..., add-requires TARGET UNIT...
Adds "Wants=" or "Requires=" dependencies, respectively, to
the specified TARGET for one or more units.
This command honors --system, --user, --runtime and --global
in a way similar to enable.
Added in version 217.
edit UNIT...
Edit or replace a drop-in snippet or the main unit file, to
extend or override the definition of the specified unit.
Depending on whether --system (the default), --user, or
--global is specified, this command will operate on the
system unit files, unit files for the calling user, or the
unit files shared between all users.
The editor (see the "Environment" section below) is invoked
on temporary files which will be written to the real location
if the editor exits successfully. After the editing is
finished, configuration is reloaded, equivalent to systemctl
daemon-reload --system or systemctl daemon-reload --user. For
edit --global, the reload is not performed and the edits will
take effect only for subsequent logins (or after a reload is
requested in a different way).
If --full is specified, a replacement for the main unit file
will be created or edited. Otherwise, a drop-in file will be
created or edited.
If --drop-in= is specified, the given drop-in file name will
be used instead of the default override.conf.
The unit must exist, i.e. its main unit file must be present.
If --force is specified, this requirement is ignored and a
new unit may be created (with --full), or a drop-in for a
nonexistent unit may be created.
If --runtime is specified, the changes will be made
temporarily in /run/ and they will be lost on the next
reboot.
If --stdin is specified, the new contents will be read from
standard input. In this mode, the old contents of the file
are discarded.
If the temporary file is empty upon exit, the modification of
the related unit is canceled.
Note that this command cannot be used to remotely edit units
and that you cannot temporarily edit units which are in
/etc/, since they take precedence over /run/.
Added in version 218.
get-default
Return the default target to boot into. This returns the
target unit name default.target is aliased (symlinked) to.
Added in version 205.
set-default TARGET
Set the default target to boot into. This sets (symlinks) the
default.target alias to the given target unit.
Added in version 205.
Machine Commands
list-machines [PATTERN...]
List the host and all running local containers with their
state. If one or more PATTERNs are specified, only containers
matching one of them are shown.
Added in version 212.
Job Commands
list-jobs [PATTERN...]
List jobs that are in progress. If one or more PATTERNs are
specified, only jobs for units matching one of them are
shown.
When combined with --after or --before the list is augmented
with information on which other job each job is waiting for,
and which other jobs are waiting for it, see above.
Added in version 233.
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.
Added in version 233.
Environment Commands
systemd supports an environment block that is passed to processes
the manager spawns. The names of the variables can contain ASCII
letters, digits, and the underscore character. Variable names
cannot be empty or start with a digit. In variable values, most
characters are allowed, but the whole sequence must be valid
UTF-8. (Note that control characters like newline (NL), tab
(TAB), or the escape character (ESC), are valid ASCII and thus
valid UTF-8). The total length of the environment block is
limited to _SC_ARG_MAX value defined by sysconf(3).
show-environment
Dump the systemd manager environment block. This is the
environment block that is passed to all processes the manager
spawns. The environment block will be dumped in
straightforward form suitable for sourcing into most shells.
If no special characters or whitespace is present in the
variable values, no escaping is performed, and the
assignments have the form "VARIABLE=value". If whitespace or
characters which have special meaning to the shell are
present, dollar-single-quote escaping is used, and
assignments have the form "VARIABLE=$'value'". This syntax is
known to be supported by bash(1), zsh(1), ksh(1), and
busybox(1)'s ash(1), but not dash(1) or fish(1).
Note that this shows the effective block, i.e. the
combination of environment variables configured via
configuration files, environment generators and via IPC (i.e.
via the set-environment described below). At the moment a
unit process is forked off this combined environment block
will be further combined with per-unit environment variables,
which are not visible in this command.
set-environment VARIABLE=VALUE...
Set one or more service manager environment variables, as
specified on the command line. This command will fail if
variable names and values do not conform to the rules listed
above.
Note that this operates on an environment block separate from
the environment block configured from service manager
configuration and environment generators. Whenever a process
is invoked the two blocks are combined (also incorporating
any per-service environment variables), and passed to it. The
show-environment verb will show the combination of the
blocks, see above.
Added in version 233.
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.
Note that this operates on an environment block separate from
the environment block configured from service manager
configuration and environment generators. Whenever a process
is invoked the two blocks are combined (also incorporating
any per-service environment variables), and passed to it. The
show-environment verb will show the combination of the
blocks, see above. Note that this means this command cannot
be used to unset environment variables defined in the service
manager configuration files or via generators.
Added in version 233.
import-environment VARIABLE...
Import all, one or more environment variables set on the
client into the systemd manager environment block. If a list
of environment variable names is passed, client-side values
are then imported into the manager's environment block. If
any names are not valid environment variable names or have
invalid values according to the rules described above, an
error is raised. If no arguments are passed, the entire
environment block inherited by the systemctl process is
imported. In this mode, any inherited invalid environment
variables are quietly ignored.
Importing of the full inherited environment block (calling
this command without any arguments) is deprecated. A shell
will set dozens of variables which only make sense locally
and are only meant for processes which are descendants of the
shell. Such variables in the global environment block are
confusing to other processes.
Added in version 209.
Manager State Commands
daemon-reload
Reload the systemd manager configuration. This will rerun all
generators (see systemd.generator(7)), reload all unit files,
and recreate the entire dependency tree. While the daemon is
being reloaded, all sockets systemd listens on behalf of user
configuration will stay accessible.
This command should not be confused with the reload command.
daemon-reexec
Reexecute the systemd manager. This will serialize the
manager state, reexecute the process and deserialize the
state again. This command is of little use except for
debugging and package upgrades. Sometimes, it might be
helpful as a heavy-weight daemon-reload. While the daemon is
being reexecuted, all sockets systemd listening on behalf of
user configuration will stay accessible.
log-level [LEVEL]
If no argument is given, print the current log level of the
manager. If an optional argument LEVEL is provided, then the
command changes the current log level of the manager to LEVEL
(accepts the same values as --log-level= described in
systemd(1)).
Added in version 244.
log-target [TARGET]
If no argument is given, print the current log target of the
manager. If an optional argument TARGET is provided, then the
command changes the current log target of the manager to
TARGET (accepts the same values as --log-target=, described
in systemd(1)).
Added in version 244.
service-watchdogs [yes|no]
If no argument is given, print the current state of service
runtime watchdogs of the manager. If an optional boolean
argument is provided, then globally enables or disables the
service runtime watchdogs (WatchdogSec=) and emergency
actions (e.g. OnFailure= or StartLimitAction=); see
systemd.service(5). The hardware watchdog is not affected by
this setting.
Added in version 244.
System Commands
is-system-running
Checks whether the system is operational. This returns
success (exit code 0) when the system is fully up and
running, specifically not in startup, shutdown or maintenance
mode, and with no failed services. Failure is returned
otherwise (exit code non-zero). In addition, the current
state is printed in a short string to standard output, see
the table below. Use --quiet to suppress this output.
Use --wait to wait until the boot process is completed before
printing the current state and returning the appropriate
error status. If --wait is in use, states initializing or
starting will not be reported, instead the command will block
until a later state (such as running or degraded) is reached.
Table 3. is-system-running output
┌──────────────┬────────────────────┬───────────┐
│ Name │ Description │ Exit Code │
├──────────────┼────────────────────┼───────────┤
│ initializing │ Early bootup, │ > 0 │
│ │ before │ │
│ │ basic.target is │ │
│ │ reached or the │ │
│ │ maintenance state │ │
│ │ entered. │ │
├──────────────┼────────────────────┼───────────┤
│ starting │ Late bootup, │ > 0 │
│ │ before the job │ │
│ │ queue becomes idle │ │
│ │ for the first │ │
│ │ time, or one of │ │
│ │ the rescue targets │ │
│ │ are reached. │ │
├──────────────┼────────────────────┼───────────┤
│ running │ The system is │ 0 │
│ │ fully operational. │ │
├──────────────┼────────────────────┼───────────┤
│ degraded │ The system is │ > 0 │
│ │ operational but │ │
│ │ one or more units │ │
│ │ failed. │ │
├──────────────┼────────────────────┼───────────┤
│ maintenance │ The rescue or │ > 0 │
│ │ emergency target │ │
│ │ is active. │ │
├──────────────┼────────────────────┼───────────┤
│ stopping │ The manager is │ > 0 │
│ │ shutting down. │ │
├──────────────┼────────────────────┼───────────┤
│ offline │ The manager is not │ > 0 │
│ │ running. │ │
│ │ Specifically, this │ │
│ │ is the operational │ │
│ │ state if an │ │
│ │ incompatible │ │
│ │ program is running │ │
│ │ as system manager │ │
│ │ (PID 1). │ │
├──────────────┼────────────────────┼───────────┤
│ unknown │ The operational │ > 0 │
│ │ state could not be │ │
│ │ determined, due to │ │
│ │ lack of resources │ │
│ │ or another error │ │
│ │ cause. │ │
└──────────────┴────────────────────┴───────────┘
Added in version 215.
default
Enter default mode. This is equivalent to systemctl isolate
default.target. This operation is blocking by default, use
--no-block to request asynchronous behavior.
rescue
Enter rescue mode. This is equivalent to systemctl isolate
rescue.target. This operation is blocking by default, use
--no-block to request asynchronous behavior.
emergency
Enter emergency mode. This is equivalent to systemctl isolate
emergency.target. This operation is blocking by default, use
--no-block to request asynchronous behavior.
halt
Shut down and halt the system. This is mostly equivalent to
systemctl start halt.target --job-mode=replace-irreversibly
--no-block, but also prints a wall message to all users. This
command is asynchronous; it will return after the halt
operation is enqueued, without waiting for it to complete.
Note that this operation will simply halt the OS kernel after
shutting down, leaving the hardware powered on. Use systemctl
poweroff for powering off the system (see below).
If combined with --force, shutdown of all running services is
skipped, however all processes are killed and all file
systems are unmounted or mounted read-only, immediately
followed by the system halt. If --force is specified twice,
the operation is immediately executed without terminating any
processes or unmounting any file systems. This may result in
data loss. Note that when --force is specified twice the halt
operation is executed by systemctl itself, and the system
manager is not contacted. This means the command should
succeed even when the system manager has crashed.
If combined with --when=, shutdown will be scheduled after
the given timestamp. And --when=cancel will cancel the
shutdown.
poweroff
Shut down and power-off the system. This is mostly equivalent
to systemctl start poweroff.target
--job-mode=replace-irreversibly --no-block, but also prints a
wall message to all users. This command is asynchronous; it
will return after the power-off operation is enqueued,
without waiting for it to complete.
This command honors --force and --when= in a similar way as
halt.
reboot
Shut down and reboot the system.
This command mostly equivalent to systemctl start
reboot.target --job-mode=replace-irreversibly --no-block, but
also prints a wall message to all users. This command is
asynchronous; it will return after the reboot operation is
enqueued, without waiting for it to complete.
If the switch --reboot-argument= is given, it will be passed
as the optional argument to the reboot(2) system call.
Options --boot-loader-entry=, --boot-loader-menu=, and
--firmware-setup can be used to select what to do after the
reboot. See the descriptions of those options for details.
This command honors --force and --when= in a similar way as
halt.
If a new kernel has been loaded via kexec --load, a kexec
will be performed instead of a reboot, unless
"SYSTEMCTL_SKIP_AUTO_KEXEC=1" has been set. If a new root
file system has been set up on "/run/nextroot/", a
soft-reboot will be performed instead of a reboot, unless
"SYSTEMCTL_SKIP_AUTO_SOFT_REBOOT=1" has been set.
Added in version 246.
kexec
Shut down and reboot the system via kexec. This command will
load a kexec kernel if one wasn't loaded yet or fail. A
kernel may be loaded earlier by a separate step, this is
particularly useful if a custom initrd or additional kernel
command line options are desired. The --force can be used to
continue without a kexec kernel, i.e. to perform a normal
reboot. The final reboot step is equivalent to systemctl
start kexec.target --job-mode=replace-irreversibly
--no-block.
To load a kernel, an enumeration is performed following the
Boot Loader Specification[1], and the default boot entry is
loaded. For this step to succeed, the system must be using
UEFI and the boot loader entries must be configured
appropriately. bootctl list may be used to list boot
entries, see bootctl(1).
This command is asynchronous; it will return after the reboot
operation is enqueued, without waiting for it to complete.
This command honors --force and --when= similarly to halt.
If a new kernel has been loaded via kexec --load, a kexec
will be performed when reboot is invoked, unless
"SYSTEMCTL_SKIP_AUTO_KEXEC=1" has been set.
soft-reboot
Shut down and reboot userspace. This is equivalent to
systemctl start soft-reboot.target
--job-mode=replace-irreversibly --no-block. This command is
asynchronous; it will return after the reboot operation is
enqueued, without waiting for it to complete.
This command honors --force and --when= in a similar way as
halt.
This operation only reboots userspace, leaving the kernel
running. See systemd-soft-reboot.service(8) for details.
If a new root file system has been set up on
"/run/nextroot/", a soft-reboot will be performed when reboot
is invoked, unless "SYSTEMCTL_SKIP_AUTO_SOFT_REBOOT=1" has
been set.
Added in version 254.
exit [EXIT_CODE]
Ask the service manager to quit. This is only supported for
user service managers (i.e. in conjunction with the --user
option) or in containers and is equivalent to poweroff
otherwise. This command is asynchronous; it will return after
the exit operation is enqueued, without waiting for it to
complete.
The service manager will exit with the specified exit code,
if EXIT_CODE is passed.
Added in version 227.
switch-root [ROOT [INIT]]
Switches to a different root directory and executes a new
system manager process below it. This is intended for use in
the initrd, and will transition from the initrd's system
manager process (a.k.a. "init" process, PID 1) to the main
system manager process which is loaded from the actual host
root files system. 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 both are omitted or the former is an empty string
it defaults to /sysroot/. If the latter is omitted or is an
empty string, a systemd binary will automatically be searched
for and used as service manager. If the system manager path
is omitted, equal to the empty string or identical to the
path to the systemd binary, 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 phase.
Added in version 209.
sleep
Put the system to sleep, through suspend, hibernate,
hybrid-sleep, or suspend-then-hibernate. The sleep operation
to use is automatically selected by
systemd-logind.service(8). By default, suspend-then-hibernate
is used, and falls back to suspend and then hibernate if not
supported. Refer to SleepOperation= setting in logind.conf(5)
for more details. This command is asynchronous, and will
return after the sleep operation is successfully enqueued. It
will not wait for the sleep/resume cycle to complete.
Added in version 256.
suspend
Suspend the system. This will trigger activation of the
special target unit suspend.target. This command is
asynchronous, and will return after the suspend operation is
successfully enqueued. It will not wait for the
suspend/resume cycle to complete.
If --force is specified, and systemd-logind returned error
for the operation, the error will be ignored and the
operation will be tried again directly through starting the
target unit.
hibernate
Hibernate the system. This will trigger activation of the
special target unit hibernate.target. This command is
asynchronous, and will return after the hibernation operation
is successfully enqueued. It will not wait for the
hibernate/thaw cycle to complete.
This command honors --force in the same way as suspend.
hybrid-sleep
Hibernate and suspend the system. This will trigger
activation of the special target unit hybrid-sleep.target.
This command is asynchronous, and will return after the
hybrid sleep operation is successfully enqueued. It will not
wait for the sleep/wake-up cycle to complete.
This command honors --force in the same way as suspend.
Added in version 196.
suspend-then-hibernate
Suspend the system and hibernate it when the battery is low,
or when the delay specified in systemd-sleep.conf elapsed.
This will trigger activation of the special target unit
suspend-then-hibernate.target. This command is asynchronous,
and will return after the hybrid sleep operation is
successfully enqueued. It will not wait for the sleep/wake-up
or hibernate/thaw cycle to complete.
This command honors --force in the same way as suspend.
Added in version 240.
Parameter Syntax
Unit commands listed above take either a single unit name
(designated as UNIT), or multiple unit specifications (designated
as PATTERN...). In the first case, the unit name with or without
a suffix must be given. If the suffix is not specified (unit name
is "abbreviated"), systemctl will append a suitable suffix,
".service" by default, and a type-specific suffix in case of
commands which operate only on specific unit types. For example,
# systemctl start sshd
and
# systemctl start sshd.service
are equivalent, as are
# systemctl isolate default
and
# systemctl isolate default.target
Note that (absolute) paths to device nodes are automatically
converted to device unit names, and other (absolute) paths to
mount unit names.
# systemctl status /dev/sda
# systemctl status /home
are equivalent to:
# systemctl status dev-sda.device
# systemctl status home.mount
In the second case, shell-style globs will be matched against the
primary names of all units currently in memory; literal unit
names, with or without a suffix, will be treated as in the first
case. This means that literal unit names always refer to exactly
one unit, but globs may match zero units and this is not
considered an error.
Glob patterns use fnmatch(3), so normal shell-style globbing
rules are used, and "*", "?", "[]" may be used. See glob(7) for
more details. The patterns are matched against the primary names
of units currently in memory, and patterns which do not match
anything are silently skipped. For example:
# systemctl stop "sshd@*.service"
will stop all [email protected] instances. Note that alias names of
units, and units that aren't in memory are not considered for
glob expansion.
For unit file commands, the specified UNIT should be the name of
the unit file (possibly abbreviated, see above), or the absolute
path to the unit file:
# systemctl enable foo.service
or
# systemctl link /path/to/foo.service
The following options are understood:
-t, --type=
The argument is a comma-separated list of unit types such as
service and socket. When units are listed with list-units,
list-dependencies, show, or status, only units of the
specified types will be shown. By default, units of all types
are 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 is a comma-separated list of unit LOAD, SUB, or
ACTIVE states. When listing units with list-units,
list-dependencies, show or status, show only those in the
specified states. Use --state=failed or --failed to show only
failed units.
As a special case, if one of the arguments is help, a list of
allowed values will be printed and the program will exit.
Added in version 206.
-p, --property=
When showing unit/job/manager properties with the show
command, limit display to properties specified in the
argument. The argument should be a comma-separated list of
property names, such as "MainPID". Unless specified, all
known properties are shown. If specified more than once, all
properties with the specified names are shown. Shell
completion is implemented for property names.
For the manager itself, systemctl show will show all
available properties, most of which are derived or closely
match the options described in systemd-system.conf(5).
Properties for units vary by unit type, so showing any unit
(even a non-existent one) is a way to list properties
pertaining to this type. Similarly, showing any job will list
properties pertaining to all jobs. Properties for units are
documented in systemd.unit(5), and the pages for individual
unit types systemd.service(5), systemd.socket(5), etc.
-P
Equivalent to --value --property=, i.e. shows the value of
the property without the property name or "=". Note that
using -P once will also affect all properties listed with
-p/--property=.
Added in version 246.
-a, --all
When listing units with list-units, also show inactive units
and units which are following other units. When showing
unit/job/manager properties, show all properties regardless
whether they are set or not.
To list all units installed in the file system, use the
list-unit-files command instead.
When listing units with list-dependencies, recursively show
dependencies of all dependent units (by default only
dependencies of target units are shown).
When used with status, show journal messages in full, even if
they include unprintable characters or are very long. By
default, fields with unprintable characters are abbreviated
as "blob data". (Note that the pager may escape unprintable
characters again.)
-r, --recursive
When listing units, also show units of local containers.
Units of local containers will be prefixed with the container
name, separated by a single colon character (":").
Added in version 212.
--reverse
Show reverse dependencies between units with
list-dependencies, i.e. follow dependencies of type
WantedBy=, RequiredBy=, UpheldBy=, PartOf=, BoundBy=, instead
of Wants= and similar.
Added in version 203.
--after
With list-dependencies, show the units that are ordered
before the specified unit. In other words, recursively list
units following the After= dependency.
Note that any After= dependency is automatically mirrored to
create a Before= dependency. Temporal dependencies may be
specified explicitly, but are also created implicitly for
units which are WantedBy= targets (see systemd.target(5)),
and as a result of other directives (for example
RequiresMountsFor=). Both explicitly and implicitly
introduced dependencies are shown with list-dependencies.
When passed to the list-jobs command, for each printed job
show which other jobs are waiting for it. May be combined
with --before to show both the jobs waiting for each job as
well as all jobs each job is waiting for.
Added in version 203.
--before
With list-dependencies, show the units that are ordered after
the specified unit. In other words, recursively list units
following the Before= dependency.
When passed to the list-jobs command, for each printed job
show which other jobs it is waiting for. May be combined with
--after to show both the jobs waiting for each job as well as
all jobs each job is waiting for.
Added in version 212.
--with-dependencies
When used with status, cat, list-units, and list-unit-files,
those commands print all specified units and the dependencies
of those units.
Options --reverse, --after, --before may be used to change
what types of dependencies are shown.
Added in version 245.
-l, --full
Do not ellipsize unit names, process tree entries, journal
output, or truncate unit descriptions in the output of
status, list-units, list-jobs, and list-timers.
Also, show installation targets in the output of is-enabled.
--value
When printing properties with show, only print the value, and
skip the property name and "=". Also see option -P above.
Added in version 230.
--show-types
When showing sockets, show the type of the socket.
Added in version 202.
--job-mode=
When queuing a new job, this option controls how to deal with
already queued jobs. It takes one of "fail", "replace",
"replace-irreversibly", "isolate", "ignore-dependencies",
"ignore-requirements", "flush", "triggering", or
"restart-dependencies". Defaults to "replace", except when
the isolate command is used which implies the "isolate" job
mode.
If "fail" is specified and a requested operation conflicts
with a pending job (more specifically: causes an already
pending start job to be reversed into a stop job or vice
versa), cause the operation to fail.
If "replace" (the default) is specified, any conflicting
pending job will be replaced, as necessary.
If "replace-irreversibly" is specified, operate like
"replace", but also mark the new jobs as irreversible. This
prevents future conflicting transactions from replacing these
jobs (or even being enqueued while the irreversible jobs are
still pending). Irreversible jobs can still be cancelled
using the cancel command. This job mode should be used on any
transaction which pulls in shutdown.target.
"isolate" is only valid for start operations and causes all
other units to be stopped when the specified unit is started.
This mode is always used when the isolate command is used.
"flush" will cause all queued jobs to be canceled when the
new job is enqueued.
If "ignore-dependencies" is specified, then all unit
dependencies are ignored for this new job and the operation
is executed immediately. If passed, no required units of the
unit passed will be pulled in, and no ordering dependencies
will be honored. This is mostly a debugging and rescue tool
for the administrator and should not be used by applications.
"ignore-requirements" is similar to "ignore-dependencies",
but only causes the requirement dependencies to be ignored,
the ordering dependencies will still be honored.
"triggering" may only be used with systemctl stop. In this
mode, the specified unit and any active units that trigger it
are stopped. See the discussion of Triggers= in
systemd.unit(5) for more information about triggering units.
"restart-dependencies" may only be used with systemctl start.
In this mode, dependencies of the specified unit will receive
restart propagation, as if a restart job had been enqueued
for the unit.
Added in version 209.
-T, --show-transaction
When enqueuing a unit job (for example as effect of a
systemctl start invocation or similar), show brief
information about all jobs enqueued, covering both the
requested job and any added because of unit dependencies.
Note that the output will only include jobs immediately part
of the transaction requested. It is possible that service
start-up program code run as effect of the enqueued jobs
might request further jobs to be pulled in. This means that
completion of the listed jobs might ultimately entail more
jobs than the listed ones.
Added in version 242.
--fail
Shorthand for --job-mode=fail.
When used with the kill command, if no units were killed, the
operation results in an error.
Added in version 227.
--check-inhibitors=
When system shutdown or sleep state is requested, this option
controls checking of inhibitor locks. It takes one of "auto",
"yes" or "no". Defaults to "auto", which will behave like
"yes" for interactive invocations (i.e. from a TTY) and "no"
for non-interactive invocations. "yes" lets the request
respect inhibitor locks. "no" lets the request ignore
inhibitor locks.
Applications can establish inhibitor locks to prevent certain
important operations (such as CD burning) from being
interrupted by system shutdown or sleep. 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 (unless privileged). However, if "no" is
specified or "auto" is specified on a non-interactive
requests, the operation will be attempted. If locks are
present, the operation may require additional privileges.
Option --force provides another way to override inhibitors.
Added in version 248.
-i
Shortcut for --check-inhibitors=no.
Added in version 198.
--dry-run
Just print what would be done. Currently supported by verbs
halt, poweroff, reboot, kexec, suspend, hibernate,
hybrid-sleep, suspend-then-hibernate, default, rescue,
emergency, and exit.
Added in version 236.
-q, --quiet
Suppress printing of the results of various commands and also
the hints about truncated log lines. This does not suppress
output of commands for which the printed output is the only
result (like show). Errors are always printed.
--no-warn
Don't generate the warnings shown by default in the following
cases:
• when systemctl is invoked without procfs mounted on
/proc/,
• when using enable or disable on units without install
information (i.e. don't have or have an empty [Install]
section),
• when using disable combined with --user on units that are
enabled in global scope,
• when a stop-ped, disable-d, or mask-ed unit still has
active triggering units,
• when a unit file is changed and requires daemon-reload.
Added in version 253.
--no-block
Do not synchronously wait for the requested operation to
finish. If this is not specified, the job will be verified,
enqueued and systemctl will wait until the unit's start-up is
completed. By passing this argument, it is only verified and
enqueued. This option may not be combined with --wait.
--wait
When used with start or restart, synchronously wait for
started units to terminate again. This option may not be
combined with --no-block. Note that this will wait forever if
any given unit never terminates (by itself or by getting
stopped explicitly); particularly services which use
"RemainAfterExit=yes".
When used with is-system-running, wait until the boot process
is completed before returning.
When used with kill, wait until the signalled units
terminate. Note that this will wait forever if any given unit
never terminates.
Added in version 232.
--user
Talk to the service manager of the calling user, rather than
the service manager of the system.
--system
Talk to the service manager of the system. This is the
implied default.
--failed
List units in failed state. This is equivalent to
--state=failed.
Added in version 233.
--no-wall
Do not send wall message before halt, power-off and 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-whom=
When used with kill, choose which processes to send a UNIX
process signal to. Must be one of main, control or all to
select whether to kill only the main process, the control
process or all processes of the unit. The main process of the
unit is the one that defines the life-time of it. A control
process of a unit is one that is invoked by the manager to
induce state changes of it. For example, all processes
started due to the ExecStartPre=, ExecStop= or ExecReload=
settings of service units are control processes. Note that
there is only one control process per unit at a time, as only
one state change is executed at a time. For services of type
Type=forking, the initial process started by the manager for
ExecStart= is a control process, while the process ultimately
forked off by that one is then considered the main process of
the unit (if it can be determined). This is different for
service units of other types, where the process forked off by
the manager for ExecStart= is always the main process itself.
A service unit consists of zero or one main process, zero or
one control process plus any number of additional processes.
Not all unit types manage processes of these types however.
For example, for mount units, control processes are defined
(which are the invocations of /usr/bin/mount and
/usr/bin/umount), but no main process is defined. If omitted,
defaults to all.
Added in version 252.
--kill-value=INT
If used with the kill command, enqueues a signal along with
the specified integer value parameter to the specified
process(es). This operation is only available for POSIX
Realtime Signals (i.e. --signal=SIGRTMIN+... or
--signal=SIGRTMAX-...), and ensures the signals are generated
via the sigqueue(3) system call, rather than kill(3). The
specified value must be a 32-bit signed integer, and may be
specified either in decimal, in hexadecimal (if prefixed with
"0x"), octal (if prefixed with "0o") or binary (if prefixed
with "0b")
If this option is used the signal will only be enqueued on
the control or main process of the unit, never on other
processes belonging to the unit, i.e. --kill-whom=all will
only affect main and control processes but no other
processes.
Added in version 254.
-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.
The special value "help" will list the known values and the
program will exit immediately, and the special value "list"
will list known values along with the numerical signal
numbers and the program will exit immediately.
--what=
Select what type of per-unit resources to remove when the
clean command is invoked, see above. Takes one of
configuration, state, cache, logs, runtime, fdstore to select
the type of resource. This option may be specified more than
once, in which case all specified resource types are removed.
Also accepts the special value all as a shortcut for
specifying all six resource types. If this option is not
specified defaults to the combination of cache, runtime and
fdstore, i.e. the three kinds of resources that are generally
considered to be redundant and can be reconstructed on next
invocation. Note that the explicit removal of the fdstore
resource type is only useful if the
FileDescriptorStorePreserve= option is enabled, since the
file descriptor store is otherwise cleaned automatically when
the unit is stopped.
Added in version 243.
-f, --force
When used with enable, overwrite any existing conflicting
symlinks.
When used with edit, create all of the specified units which
do not already exist.
When used with suspend, hibernate, hybrid-sleep, or
suspend-then-hibernate, the error returned by systemd-logind
will be ignored, and the operation will be performed directly
through starting the corresponding units.
When used with halt, poweroff, reboot, or kexec, execute the
selected operation without shutting down all units. However,
all processes will be killed forcibly and all file systems
are unmounted or remounted read-only. This is hence a drastic
but relatively safe option to request an immediate reboot. If
--force is specified twice for these operations (with the
exception of kexec), they will be executed immediately,
without terminating any processes or unmounting any file
systems.
Warning
Specifying --force twice with any of these operations
might result in data loss. Note that when --force is
specified twice the selected operation is executed by
systemctl itself, and the system manager is not
contacted. This means the command should succeed even
when the system manager has crashed.
--message=
When used with halt, poweroff or reboot, set a short message
explaining the reason for the operation. The message will be
logged together with the default shutdown message.
Added in version 225.
--now
When used with enable, the units will also be started. When
used with disable or mask, the units will also be stopped.
The start or stop operation is only carried out when the
respective enable or disable operation has been successful.
Added in version 220.
--root=
When used with enable/disable/is-enabled (and related
commands), use the specified root path when looking for unit
files. If this option is present, systemctl will operate on
the file system directly, instead of communicating with the
systemd daemon to carry out changes.
--image=image
Takes a path to a disk image file or block device node. If
specified, all operations are applied to file system in the
indicated disk image. This option is similar to --root=, but
operates on file systems stored in disk images or block
devices. The disk image should either contain just a file
system or a set of file systems within a GPT partition table,
following the Discoverable Partitions Specification[2]. For
further information on supported disk images, see
systemd-nspawn(1)'s switch of the same name.
Added in version 252.
--image-policy=policy
Takes an image policy string as argument, as per
systemd.image-policy(7). The policy is enforced when
operating on the disk image specified via --image=, see
above. If not specified defaults to the "*" policy, i.e. all
recognized file systems in the image are used.
--runtime
When used with enable, disable, edit, (and related commands),
make changes only temporarily, so that they are lost on the
next reboot. This will have the effect that changes are not
made in subdirectories of /etc/ but in /run/, with identical
immediate effects, however, since the latter is lost on
reboot, the changes are lost too.
Similarly, when used with set-property, make changes only
temporarily, so that they are lost on the next reboot.
--preset-mode=
Takes one of "full" (the default), "enable-only",
"disable-only". When used with the preset or preset-all
commands, controls whether units shall be disabled and
enabled according to the preset rules, or only enabled, or
only disabled.
Added in version 215.
-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, or 0 to disable journal output. Defaults to
10.
-o, --output=
When used with status, controls the formatting of the journal
entries that are shown. For the available choices, see
journalctl(1). Defaults to "short".
--firmware-setup
When used with the reboot, poweroff, or halt command,
indicate to the system's firmware to reboot into the firmware
setup interface for the next boot. Note that this
functionality is not available on all systems.
Added in version 220.
--boot-loader-menu=timeout
When used with the reboot, poweroff, or halt command,
indicate to the system's boot loader to show the boot loader
menu on the following boot. Takes a time value as parameter —
indicating the menu timeout. Pass zero in order to disable
the menu timeout. Note that not all boot loaders support this
functionality.
Added in version 242.
--boot-loader-entry=ID
When used with the reboot, poweroff, or halt command,
indicate to the system's boot loader to boot into a specific
boot loader entry on the following boot. Takes a boot loader
entry identifier as argument, or "help" in order to list
available entries. Note that not all boot loaders support
this functionality.
Added in version 242.
--reboot-argument=
This switch is used with reboot. The value is architecture
and firmware specific. As an example, "recovery" might be
used to trigger system recovery, and "fota" might be used to
trigger a “firmware over the air” update.
Added in version 246.
--plain
When used with list-dependencies, list-units or
list-machines, the output is printed as a list instead of a
tree, and the bullet circles are omitted.
Added in version 203.
--timestamp=
Change the format of printed timestamps. The following values
may be used:
pretty (this is the default)
"Day YYYY-MM-DD HH:MM:SS TZ"
Added in version 248.
unix
"@seconds-since-the-epoch"
Added in version 251.
us, μs
"Day YYYY-MM-DD HH:MM:SS.UUUUUU TZ"
Added in version 248.
utc
"Day YYYY-MM-DD HH:MM:SS UTC"
Added in version 248.
us+utc, μs+utc
"Day YYYY-MM-DD HH:MM:SS.UUUUUU UTC"
Added in version 248.
Added in version 247.
--mkdir
When used with bind, creates the destination file or
directory before applying the bind mount. Note that even
though the name of this option suggests that it is suitable
only for directories, this option also creates the
destination file node to mount over if the object to mount is
not a directory, but a regular file, device node, socket or
FIFO.
Added in version 248.
--marked
Only allowed with reload-or-restart. Enqueues restart jobs
for all units that have the "needs-restart" mark, and reload
jobs for units that have the "needs-reload" mark. When a unit
marked for reload does not support reload, restart will be
queued. Those properties can be set using set-property
Markers=....
Unless --no-block is used, systemctl will wait for the queued
jobs to finish.
Added in version 248.
--read-only
When used with bind, creates a read-only bind mount.
Added in version 248.
--drop-in=NAME
When used with edit, use NAME as the drop-in file name
instead of override.conf.
Added in version 253.
--when=
When used with halt, poweroff, reboot or kexec, schedule the
action to be performed at the given timestamp, which should
adhere to the syntax documented in systemd.time(7) section
"PARSING TIMESTAMPS". Specially, if "show" is given, the
currently scheduled action will be shown, which can be
canceled by passing an empty string or "cancel".
Added in version 254.
--stdin
When used with edit, the contents of the file will be read
from standard input and the editor will not be launched. In
this mode, the old contents of the file are completely
replaced. This is useful to "edit" unit files from scripts:
$ systemctl edit --drop-in=limits.conf --stdin some-service.service <<EOF
[Unit]
AllowedCPUs=7,11
EOF
Multiple drop-ins may be "edited" in this mode; the same
contents will be written to all of them.
Added in version 256.
-H, --host=
Execute the operation remotely. Specify a hostname, or a
username and hostname separated by "@", to connect to. The
hostname may optionally be suffixed by a port ssh is
listening on, separated by ":", and then a container name,
separated by "/", which connects directly to a specific
container on the specified host. This will use SSH to talk to
the remote machine manager instance. Container names may be
enumerated with machinectl -H HOST. Put IPv6 addresses in
brackets.
-M, --machine=
Execute operation on a local container. Specify a container
name to connect to, optionally prefixed by a user name to
connect as and a separating "@" character. If the special
string ".host" is used in place of the container name, a
connection to the local system is made (which is useful to
connect to a specific user's user bus: "--user
[email protected]"). If the "@" syntax is not used, the
connection is made as root user. If the "@" syntax is used
either the left hand side or the right hand side may be
omitted (but not both) in which case the local user name and
".host" are implied.
-C, --capsule=
Execute operation on a capsule. Specify a capsule name to
connect to. See [email protected](5) for details about
capsules.
Added in version 256.
--no-pager
Do not pipe output into a pager.
--legend=BOOL
Enable or disable printing of the legend, i.e. column headers
and the footer with hints. The legend is printed by default,
unless disabled with --quiet or similar.
-h, --help
Print a short help text and exit.
--version
Print a short version string and exit.
On success, 0 is returned, a non-zero failure code otherwise.
systemctl uses the return codes defined by LSB, as defined in LSB
3.0.0[3].
Table 4. LSB return codes
┌───────┬────────────────────┬────────────────────┐
│ Value │ Description in LSB │ Use in systemd │
├───────┼────────────────────┼────────────────────┤
│ 0 │ "program is │ unit is active │
│ │ running or service │ │
│ │ is OK" │ │
├───────┼────────────────────┼────────────────────┤
│ 1 │ "program is dead │ unit not failed │
│ │ and /var/run pid │ (used by │
│ │ file exists" │ is-failed) │
├───────┼────────────────────┼────────────────────┤
│ 2 │ "program is dead │ unused │
│ │ and /var/lock lock │ │
│ │ file exists" │ │
├───────┼────────────────────┼────────────────────┤
│ 3 │ "program is not │ unit is not active │
│ │ running" │ │
├───────┼────────────────────┼────────────────────┤
│ 4 │ "program or │ no such unit │
│ │ service status is │ │
│ │ unknown" │ │
└───────┴────────────────────┴────────────────────┘
The mapping of LSB service states to systemd unit states is
imperfect, so it is better to not rely on those return values but
to look for specific unit states and substates instead.
$SYSTEMD_EDITOR
Editor to use when editing units; overrides $EDITOR and
$VISUAL. If neither $SYSTEMD_EDITOR nor $EDITOR nor $VISUAL
are present or if it is set to an empty string or if their
execution failed, systemctl will try to execute well known
editors in this order: editor(1), nano(1), vim(1), vi(1).
Added in version 218.
$SYSTEMD_LOG_LEVEL
The maximum log level of emitted messages (messages with a
higher log level, i.e. less important ones, will be
suppressed). Takes a comma-separated list of values. A value
may be either one of (in order of decreasing importance)
emerg, alert, crit, err, warning, notice, info, debug, or an
integer in the range 0...7. See syslog(3) for more
information. Each value may optionally be prefixed with one
of console, syslog, kmsg or journal followed by a colon to
set the maximum log level for that specific log target (e.g.
SYSTEMD_LOG_LEVEL=debug,console:info specifies to log at
debug level except when logging to the console which should
be at info level). Note that the global maximum log level
takes priority over any per target maximum log levels.
$SYSTEMD_LOG_COLOR
A boolean. If true, messages written to the tty will be
colored according to priority.
This setting is only useful when messages are written
directly to the terminal, because journalctl(1) and other
tools that display logs will color messages based on the log
level on their own.
$SYSTEMD_LOG_TIME
A boolean. If true, console log messages will be prefixed
with a timestamp.
This setting is only useful when messages are written
directly to the terminal or a file, because journalctl(1) and
other tools that display logs will attach timestamps based on
the entry metadata on their own.
$SYSTEMD_LOG_LOCATION
A boolean. If true, messages will be prefixed with a filename
and line number in the source code where the message
originates.
Note that the log location is often attached as metadata to
journal entries anyway. Including it directly in the message
text can nevertheless be convenient when debugging programs.
$SYSTEMD_LOG_TARGET
The destination for log messages. One of console (log to the
attached tty), console-prefixed (log to the attached tty but
with prefixes encoding the log level and "facility", see
syslog(3), kmsg (log to the kernel circular log buffer),
journal (log to the journal), journal-or-kmsg (log to the
journal if available, and to kmsg otherwise), auto (determine
the appropriate log target automatically, the default), null
(disable log output).
$SYSTEMD_PAGER
Pager to use when --no-pager is not given; overrides $PAGER.
If neither $SYSTEMD_PAGER nor $PAGER are set, a set of
well-known pager implementations are tried in turn, including
less(1) and more(1), until one is found. If no pager
implementation is discovered no pager is invoked. Setting
this environment variable to an empty string or the value
"cat" is equivalent to passing --no-pager.
Note: if $SYSTEMD_PAGERSECURE is not set, $SYSTEMD_PAGER (as
well as $PAGER) will be silently ignored.
$SYSTEMD_LESS
Override the options passed to less (by default "FRSXMK").
Users might want to change two options in particular:
K
This option instructs the pager to exit immediately when
Ctrl+C is pressed. To allow less to handle Ctrl+C itself
to switch back to the pager command prompt, unset this
option.
If the value of $SYSTEMD_LESS does not include "K", and
the pager that is invoked is less, Ctrl+C will be ignored
by the executable, and needs to be handled by the pager.
X
This option instructs the pager to not send termcap
initialization and deinitialization strings to the
terminal. It is set by default to allow command output to
remain visible in the terminal even after the pager
exits. Nevertheless, this prevents some pager
functionality from working, in particular paged output
cannot be scrolled with the mouse.
Note that setting the regular $LESS environment variable has
no effect for less invocations by systemd tools.
See less(1) for more discussion.
$SYSTEMD_LESSCHARSET
Override the charset passed to less (by default "utf-8", if
the invoking terminal is determined to be UTF-8 compatible).
Note that setting the regular $LESSCHARSET environment
variable has no effect for less invocations by systemd tools.
$SYSTEMD_PAGERSECURE
Takes a boolean argument. When true, the "secure" mode of the
pager is enabled; if false, disabled. If $SYSTEMD_PAGERSECURE
is not set at all, secure mode is enabled if the effective
UID is not the same as the owner of the login session, see
geteuid(2) and sd_pid_get_owner_uid(3). In secure mode,
LESSSECURE=1 will be set when invoking the pager, and the
pager shall disable commands that open or create new files or
start new subprocesses. When $SYSTEMD_PAGERSECURE is not set
at all, pagers which are not known to implement secure mode
will not be used. (Currently only less(1) implements secure
mode.)
Note: when commands are invoked with elevated privileges, for
example under sudo(8) or pkexec(1), care must be taken to
ensure that unintended interactive features are not enabled.
"Secure" mode for the pager may be enabled automatically as
describe above. Setting SYSTEMD_PAGERSECURE=0 or not removing
it from the inherited environment allows the user to invoke
arbitrary commands. Note that if the $SYSTEMD_PAGER or $PAGER
variables are to be honoured, $SYSTEMD_PAGERSECURE must be
set too. It might be reasonable to completely disable the
pager using --no-pager instead.
$SYSTEMD_COLORS
Takes a boolean argument. When true, systemd and related
utilities will use colors in their output, otherwise the
output will be monochrome. Additionally, the variable can
take one of the following special values: "16", "256" to
restrict the use of colors to the base 16 or 256 ANSI colors,
respectively. This can be specified to override the automatic
decision based on $TERM and what the console is connected to.
$SYSTEMD_URLIFY
The value must be a boolean. Controls whether clickable links
should be generated in the output for terminal emulators
supporting this. This can be specified to override the
decision that systemd makes based on $TERM and other
conditions.
systemd(1), journalctl(1), loginctl(1), machinectl(1),
systemd.unit(5), systemd.resource-control(5), systemd.special(7),
wall(1), systemd.preset(5), systemd.generator(7), glob(7)
1. Boot Loader Specification
https://uapi-group.org/specifications/specs/boot_loader_specification
2. Discoverable Partitions Specification
https://uapi-group.org/specifications/specs/discoverable_partitions_specification
3. LSB 3.0.0
http://refspecs.linuxbase.org/LSB_3.0.0/LSB-PDA/LSB-PDA/iniscrptact.html
This page is part of the systemd (systemd system and service
manager) project. Information about the project can be found at
⟨http://www.freedesktop.org/wiki/Software/systemd⟩. If you have
a bug report for this manual page, see
⟨http://www.freedesktop.org/wiki/Software/systemd/#bugreports⟩.
This page was obtained from the project's upstream Git repository
⟨https://github.com/systemd/systemd.git⟩ on 2024-06-14. (At that
time, the date of the most recent commit that was found in the
repository was 2024-06-13.) If you discover any rendering
problems in this HTML version of the page, or you believe there
is a better or more up-to-date source for the page, or you have
corrections or improvements to the information in this COLOPHON
(which is not part of the original manual page), send a mail to
[email protected]
systemd 257~devel SYSTEMCTL(1)
Pages that refer to this page: bootctl(1), hostnamectl(1), htop(1), journalctl(1), localectl(1), loginctl(1), pcp-check(1), pcpintro(1), pmie(1), pmlogger(1), run0(1), systemd(1), systemd-analyze(1), systemd-ask-password(1), systemd-cat(1), systemd-cgls(1), systemd-cgtop(1), systemd-escape(1), systemd-mount(1), systemd-notify(1), systemd-run(1), systemd-tty-ask-password-agent(1), timedatectl(1), reboot(2), sd_notify(3), [email protected](5), org.freedesktop.LogControl1(5), org.freedesktop.login1(5), [email protected](5), srp_daemon.service(5), systemd.automount(5), systemd.device(5), systemd.exec(5), systemd.kill(5), systemd.mount(5), systemd.path(5), systemd.preset(5), systemd.service(5), systemd.socket(5), systemd.swap(5), systemd.target(5), systemd.timer(5), systemd.unit(5), daemon(7), systemd-boot(7), systemd.directives(7), systemd.environment-generator(7), systemd.generator(7), systemd.index(7), systemd.special(7), systemd.time(7), autofs(8), poweroff(8), runlevel(8), shutdown(8), systemd-debug-generator(8), systemd-environment-d-generator(8), systemd-machined.service(8), systemd-poweroff.service(8), systemd-rc-local-generator(8), systemd-run-generator(8), systemd-socket-proxyd(8), systemd-soft-reboot.service(8), systemd-suspend.service(8), telinit(8)
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