systemctl(1)
NAME
systemctl - Control the systemd system and service manager
SYNOPSIS
systemctl [OPTIONS...] COMMAND [NAME...]
DESCRIPTION
systemctl may be used to introspect and control the state of the "systemd" system and service manager. Please refer to systemd(1) for an introduction into the basic concepts and functionality this tool manages.
OPTIONS
The following options are understood:
-t, --type=
The argument should be a comma-separated list of unit types such as
service and socket.
If one of the arguments is a unit type, when listing units, limit
display to certain unit types. Otherwise, units of all types will
be shown.
As a special case, if one of the arguments is help, a list of
allowed values will be printed and the program will exit.
--state=
The argument should be a comma-separated list of unit LOAD, SUB, or
ACTIVE states. When listing units, show only those in the specified
states. Use --state=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.
-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. Those properties are documented 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.
-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).
-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 (":").
--reverse
Show reverse dependencies between units with list-dependencies,
i.e. follow dependencies of type WantedBy=, RequiredBy=, PartOf=,
BoundBy=, instead of Wants= and similar.
--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.
--before
With list-dependencies, show the units that are ordered after the
specified unit. In other words, recursively list units following
the Before= dependency.
-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 "=".
--show-types
When showing sockets, show the type of the socket.
--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" or "flush". 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.
"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.
--fail
Shorthand for --job-mode=fail.
When used with the kill command, if no units were killed, the
operation results in an error.
-i, --ignore-inhibitors
When system shutdown or a sleep state is requested, ignore
inhibitor locks. Applications can establish inhibitor locks to
avoid that certain important operations (such as CD burning or
suchlike) are interrupted by system shutdown or a sleep state. Any
user may take these locks and privileged users may override these
locks. If any locks are taken, shutdown and sleep state requests
will normally fail (regardless of whether privileged or not) and a
list of active locks is printed. However, if --ignore-inhibitors is
specified, the locks are ignored and not printed, and the operation
attempted anyway, possibly requiring additional privileges.
-q, --quiet
Suppress 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-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
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".
--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.
--no-wall
Do not send wall message before halt, power-off, reboot.
--global
When used with enable and disable, operate on the global user
configuration directory, thus enabling or disabling a unit file
globally for all future logins of all users.
--no-reload
When used with enable and disable, do not implicitly reload daemon
configuration after executing the changes.
--no-ask-password
When used with start and related commands, disables asking for
passwords. Background services may require input of a password or
passphrase string, for example to unlock system hard disks or
cryptographic certificates. Unless this option is specified and the
command is invoked from a terminal, systemctl will query the user
on the terminal for the necessary secrets. Use this option to
switch this behavior off. In this case, the password must be
supplied by some other means (for example graphical password
agents) or the service might fail. This also disables querying the
user for authentication for privileged operations.
--kill-who=
When used with kill, choose which processes to send a 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 /bin/mount and /bin/umount),
but no main process is defined. If omitted, defaults to all.
-s, --signal=
When used with kill, choose which signal to send to selected
processes. Must be one of the well-known signal specifiers such as
SIGTERM, SIGINT or SIGSTOP. If omitted, defaults to SIGTERM.
-f, --force
When used with enable, overwrite any existing conflicting symlinks.
When used with edit, create all of the specified units which do not
already exist.
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 hangs or crashed.
--message=
When used with halt, poweroff, reboot or kexec, set a short message
explaining the reason for the operation. The message will be logged
together with the default shutdown message.
--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.
--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.
--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.
-n, --lines=
When used with status, controls the number of journal lines to
show, counting from the most recent ones. Takes a positive integer
argument. Defaults to 10.
-o, --output=
When used with status, controls the formatting of the journal
entries that are shown. For the available choices, see
journalctl(1). Defaults to "short".
--firmware-setup
When used with the reboot command, indicate to the system's
firmware to boot into setup mode. Note that this is currently only
supported on some EFI systems and only if the system was booted in
EFI mode.
--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.
-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 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.
-M, --machine=
Execute operation on a local container. Specify a container name to
connect to.
--no-pager
Do not pipe output into a pager.
--no-legend
Do not print the legend, i.e. column headers and the footer with
hints.
-h, --help
Print a short help text and exit.
--version
Print a short version string and exit.
COMMANDS
The following commands are understood:
Unit Commands
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.
This is the default command.
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=.
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.
Also see --all and --state=.
start PATTERN...
Start (activate) one or more units specified on the command line.
Note that glob patterns operate on the set of primary 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.
stop PATTERN...
Stop (deactivate) one or more units specified on the command line.
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...
Restart one or more units specified on the command line. If the
units are not running yet, they will be started.
try-restart PATTERN...
Restart 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, restart 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, restart them
instead. This does nothing if the units are not running.
isolate NAME
Start the unit specified on the command line and its dependencies
and stop all others. If a unit name with no extension is given, an
extension of ".target" will be assumed.
This is similar to changing the runlevel in a traditional init
system. The isolate command will immediately stop processes that
are not enabled in the new unit, possibly including the graphical
environment or terminal you are currently using.
Note that this is allowed only on units where AllowIsolate= is
enabled. See systemd.unit(5) for details.
kill PATTERN...
Send a signal to one or more processes of the unit. Use --kill-who=
to select which process to kill. Use --signal= to select the signal
to send.
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 are in a "failed" state.
Returns an exit code 0 if at least one has failed, non-zero
otherwise. Unless --quiet is specified, this will also print the
current unit state to standard output.
status [PATTERN...|PID...]]
Show terse runtime status information about one or more units,
followed by most recent log data from the journal. If no units are
specified, show system status. If combined with --all, also show
the status of all units (subject to limitations specified with -t).
If a PID is passed, show information about the unit the process
belongs to.
This function is intended to generate human-readable output. If you
are looking for computer-parsable output, use show instead. 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.
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.
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 may 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.
set-property NAME ASSIGNMENT...
Set the specified unit properties at runtime where this is
supported. This allows changing configuration parameter properties
such as resource control settings at runtime. Not all properties
may be changed at runtime, but many resource control settings
(primarily those in systemd.resource-control(5)) may. The changes
are applied instantly, and stored on disk for future boots, unless
--runtime is passed, in which case the settings only apply until
the next reboot. The syntax of the property assignment follows
closely the syntax of assignments in unit files.
Example: systemctl set-property foobar.service CPUShares=777
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. Like
unit file configuration settings, assigning the empty list to list
parameters will reset the list.
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.
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 restarted or reset with this
command.
list-dependencies [NAME]
Shows units required and wanted by the specified unit. This
recursively lists units following the Requires=, Requisite=,
ConsistsOf=, Wants=, BindsTo= dependencies. If no unit is
specified, default.target 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.
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).
enable NAME..., 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 foo@bar.service),
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.
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.
Enabling units should not be confused with starting (activating)
units, as done by the start command. Enabling and starting units is
orthogonal: units may be enabled without being started and started
without being enabled. Enabling simply hooks the unit into various
suggested places (for example, so that the unit is automatically
started on boot or when a particular kind of hardware is plugged
in). Starting actually spawns the daemon process (in case of
service units), or binds the socket (in case of socket units), and
so on.
Depending on whether --system, --user, --runtime, or --global is
specified, this enables the unit for the system, for the calling
user only, for only this boot of the system, or for all future
logins of all users, or only this boot. Note that in the last case,
no systemd daemon configuration is reloaded.
Using enable on masked units is not supported and results in an
error.
disable NAME...
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.
This command honors --system, --user, --runtime and --global in a
similar way as enable.
reenable NAME...
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.
preset NAME...
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. NAME must be the real unit name, any
alias names are ignored silently.
For more information on the preset policy format, see
systemd.preset(5). For more information on the concept of presets,
please consult the Preset[1] document.
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.
is-enabled NAME...
Checks whether any of the specified unit files are enabled (as with
enable). Returns an exit code of 0 if at least one is enabled,
non-zero otherwise. Prints the current enable status (see table).
To suppress this output, use --quiet. To show installation targets,
use --full.
Table 1. is-enabled output
Name Description Exit Code
"enabled" Enabled via
.wants/, .requires/
"enabled-runtime" or alias symlinks
(permanently in 0
/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.
"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.
"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.
mask NAME...
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.
unmask NAME...
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.
link PATH...
Link a unit file that is not in the unit file search paths 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.
revert NAME...
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.
add-wants TARGET NAME..., add-requires TARGET NAME...
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.
edit NAME...
Edit a drop-in snippet or a whole replacement file if --full is
specified, to extend or override the specified unit.
Depending on whether --system (the default), --user, or --global is
specified, this command creates a drop-in file for each unit either
for the system, for the calling user, or for all futures logins of
all users. Then, 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.
If --full is specified, this will copy the original units instead
of creating drop-in files.
If --force is specified and any units do not already exist, new
unit files will be opened for editing.
If --runtime is specified, the changes will be made temporarily in
/run and they will be lost on the next reboot.
If the temporary file is empty upon exit, the modification of the
related unit is canceled.
After the units have been edited, systemd configuration is reloaded
(in a way that is equivalent to daemon-reload).
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.
get-default
Return the default target to boot into. This returns the target
unit name default.target is aliased (symlinked) to.
set-default NAME
Set the default target to boot into. This sets (symlinks) the
default.target alias to the given target unit.
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.
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.
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.
Environment Commands
show-environment
Dump the systemd manager environment block. The environment block
will be dumped in straight-forward form suitable for sourcing into
a shell script. This environment block will be passed to all
processes the manager spawns.
set-environment VARIABLE=VALUE...
Set one or more systemd manager environment variables, as specified
on the command line.
unset-environment VARIABLE...
Unset one or more systemd manager environment variables. If only a
variable name is specified, it will be removed regardless of its
value. If a variable and a value are specified, the variable is
only removed if it has the specified value.
import-environment [VARIABLE...]
Import all, one or more environment variables set on the client
into the systemd manager environment block. If no arguments are
passed, the entire environment block is imported. Otherwise, a list
of one or more environment variable names should be passed, whose
client-side values are then imported into the manager's environment
block.
Manager Lifecycle 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.
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.
Table 2. 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, before > 0
the job queue
becomes idle for
the first time, or
one of the rescue
targets are
reached.
running The system is fully 0
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.
default
Enter default mode. This is mostly equivalent to isolate
default.target.
rescue
Enter rescue mode. This is mostly equivalent to isolate
rescue.target, but also prints a wall message to all users.
emergency
Enter emergency mode. This is mostly equivalent to isolate
emergency.target, but also prints a wall message to all users.
halt
Shut down and halt the system. This is mostly equivalent to start
halt.target --job-mode=replace-irreversibly, but also prints a wall
message to all users. If combined with --force, shutdown of all
running services is skipped, however all processes are killed and
all file systems are unmounted or mounted read-only, immediately
followed by the system halt. If --force is specified twice, the
operation is immediately executed without terminating any processes
or unmounting any file systems. This may result in data loss. 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 hangs
or crashed.
poweroff
Shut down and power-off the system. This is mostly equivalent to
start poweroff.target --job-mode=replace-irreversibly, but also
prints a wall message to all users. If combined with --force,
shutdown of all running services is skipped, however all processes
are killed and all file systems are unmounted or mounted read-only,
immediately followed by the powering off. If --force is specified
twice, the operation is immediately executed without terminating
any processes or unmounting any file systems. This may result in
data loss. Note that when --force is specified twice the power-off
operation is executed by systemctl itself, and the system manager
is not contacted. This means the command should succeed even when
the system manager hangs or crashed.
reboot [arg]
Shut down and reboot the system. This is mostly equivalent to start
reboot.target --job-mode=replace-irreversibly, but also prints a
wall message to all users. If combined with --force, shutdown of
all running services is skipped, however all processes are killed
and all file systems are unmounted or mounted read-only,
immediately followed by the reboot. If --force is specified twice,
the operation is immediately executed without terminating any
processes or unmounting any file systems. This may result in data
loss. Note that when --force is specified twice the reboot
operation is executed by systemctl itself, and the system manager
is not contacted. This means the command should succeed even when
the system manager hangs or crashed.
If the optional argument arg is given, it will be passed as the
optional argument to the reboot(2) system call. 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.
kexec
Shut down and reboot the system via kexec. This is mostly
equivalent to start kexec.target --job-mode=replace-irreversibly,
but also prints a wall message to all users. If combined with
--force, shutdown of all running services is skipped, however all
processes are killed and all file systems are unmounted or mounted
read-only, immediately followed by the reboot.
exit [EXIT_CODE]
Ask the systemd 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.
The systemd manager can exit with a non-zero exit code if the
optional argument EXIT_CODE is given.
switch-root ROOT [INIT]
Switches to a different root directory and executes a new system
manager process below it. This is intended for usage in initial RAM
disks ("initrd"), and will transition from the initrd's system
manager process (a.k.a. "init" process) to the main system manager
process which is loaded from the actual host volume. This call
takes two arguments: the directory that is to become the new root
directory, and the path to the new system manager binary below it
to execute as PID 1. If the latter is omitted or the empty string,
a systemd binary will automatically be searched for and used as
init. If the system manager path is omitted, 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.
suspend
Suspend the system. This will trigger activation of the special
suspend.target target.
hibernate
Hibernate the system. This will trigger activation of the special
hibernate.target target.
hybrid-sleep
Hibernate and suspend the system. This will trigger activation of
the special hybrid-sleep.target target.
Parameter Syntax
Unit commands listed above take either a single unit name (designated
as NAME), 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 sshd@.service 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 NAME 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
EXIT STATUS
On success, 0 is returned, a non-zero failure code otherwise.
ENVIRONMENT
$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).
$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.
$SYSTEMD_LESS
Override the options passed to less (by default "FRSXMK").
$SYSTEMD_LESSCHARSET
Override the charset passed to less (by default "utf-8", if the
invoking terminal is determined to be UTF-8 compatible).
SEE ALSO
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)
NOTES
1. Preset
http://freedesktop.org/wiki/Software/systemd/Preset
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