The following commands are understood:
- 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 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 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 (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 (deactivate) one or more units specified on the command line.
- Asks all units listed on the command line to reload their configuration. Note that this will reload the service-specific configuration, not the unit configuration file of systemd. If you want systemd to reload the configuration file of a unit, use the daemon-reload command. In other words: for the example case of Apache, this will reload Apache's httpd.conf in the web server, not the apache.service systemd unit file.
This command should not be confused with the daemon-reload command.
- Restart one or more units specified on the command line. If the units are not running yet, they will be started.
- Restart one or more units specified on the command line if the units are running. This does nothing if units are not running.
- Reload one or more units if they support it. If not, restart them instead. If the units are not running yet, they will be started.
- Reload one or more units if they support it. If not, restart them instead. This does nothing if the units are not running.
- 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.
- 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.
- 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.
- 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.
- 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 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.
- 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 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.
- 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 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.
- 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 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 email@example.com), 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.
- 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 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.
- 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 m[blue]Presetm document.
- 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.
- 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/ or alias symlinks (permanently in /etc/systemd/system/, or transiently in /run/systemd/system/). || 0 |
| "enabled-runtime" |
| "linked" || Made available through one or more symlinks to the unit file (permanently in /etc/systemd/system/ or transiently in /run/systemd/system/), even though the unit file might reside outside of the unit file search path. || > 0 |
| "linked-runtime" |
| "masked" || Completely disabled, so that any start operation on it fails (permanently in /etc/systemd/system/ or transiently in /run/systemd/systemd/). || > 0 |
| "masked-runtime" |
| "static" || The unit file is not enabled, and has no provisions for enabling in the "[Install]" unit file section. || 0 |
| "indirect" || The unit file itself is not enabled, but it has a non-empty Also= setting in the "[Install]" unit file section, listing other unit files that might be enabled. || 0 |
| "disabled" || The unit file is not enabled, but contains an "[Install]" section with installation instructions. || > 0 |
| "generated" || The unit file was generated dynamically via a generator tool. See systemd.generator(7). Generated unit files may not be enabled, they are enabled implicitly by their generator. || 0 |
| "transient" || The unit file has been created dynamically with the runtime API. Transient units may not be enabled. || 0 |
| "bad" || The unit file is 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. || > 0 |
- 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 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 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 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 TARGETNAME..., add-requires TARGETNAME...
- 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 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.
- Return the default target to boot into. This returns the target unit name default.target is aliased (symlinked) to.
- Set the default target to boot into. This sets (symlinks) the default.target alias to the given target unit.
- 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.
- List jobs that are in progress. If one or more PATTERNs are specified, only jobs for units matching one of them are shown.
- Cancel one or more jobs specified on the command line by their numeric job IDs. If no job ID is specified, cancel all pending jobs.
- Dump the systemd manager environment block. The environment block will be dumped in straight-forward form suitable for sourcing into a shell script. This environment block will be passed to all processes the manager spawns.
- Set one or more systemd manager environment variables, as specified on the command line.
- Unset one or more systemd manager environment variables. If only a variable name is specified, it will be removed regardless of its value. If a variable and a value are specified, the variable is only removed if it has the specified value.
- 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
- 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.
- 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.
- 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, before basic.target is reached or the maintenance state entered. || > 0 |
| starting || Late bootup, before the job queue becomes idle for the first time, or one of the rescue targets are reached. || > 0 |
| running || The system is fully operational. || 0 |
| degraded || The system is operational but one or more units failed. || > 0 |
| maintenance || The rescue or emergency target is active. || > 0 |
| stopping || The manager is shutting down. || > 0 |
| offline || The manager is not running. Specifically, this is the operational state if an incompatible program is running as system manager (PID 1). || > 0 |
| unknown || The operational state could not be determined, due to lack of resources or another error cause. || > 0 |
- Enter default mode. This is mostly equivalent to isolate default.target.
- Enter rescue mode. This is mostly equivalent to isolate rescue.target, but also prints a wall message to all users.
- Enter emergency mode. This is mostly equivalent to isolate emergency.target, but also prints a wall message to all users.
- Shut down and halt the system. This is mostly equivalent to start halt.target --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.
- 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.
- 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.
- 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.
- 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.
- 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 the system. This will trigger activation of the special suspend.target target.
- Hibernate the system. This will trigger activation of the special hibernate.target target.
- Hibernate and suspend the system. This will trigger activation of the special hybrid-sleep.target target.
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
# systemctl start sshd.service
are equivalent, as are
# systemctl isolate default
# 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
# systemctl link /path/to/foo.service
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)