org.freedesktop.systemd1
systemd
org.freedesktop.systemd1
5
org.freedesktop.systemd1
The D-Bus interface of systemd-systemdd
Introduction
systemd1 and its
auxiliary daemons expose a number of APIs over D-Bus. This page describes the various APIs exposed by the
system and service manager itself, and does not cover the auxiliary daemons.
The service manager exposes a number of objects on the bus: one
Manager object as central entry point for clients, and individual objects
for each unit and for each queued job. The unit objects each implement a generic
Unit interface plus a type-specific interface. For example, service units
implement org.freedesktop.systemd1.Unit as well as
org.freedesktop.system1.Service. The manager object can be used to list
unit and job objects, or to directly convert a unit name or job id into a bus path of the corresponding
D-Bus object.
Properties exposing time values are usually encoded in microseconds (usec) on the bus, even if
their corresponding settings in the unit files are in seconds.
In contrast to most of the other services of the systemd suite PID 1 does not use PolicyKit for
controlling access to privileged operations, but relies exclusively on the low-level D-Bus policy
language. (This is done in order to avoid a cyclic dependency between PolicyKit and systemd/PID 1.) This
means that sensitive operations exposed by PID 1 on the bus are generally not available to unprivileged
processes directly. However some (such as shutdown/reboot/suspend) are made available through the D-Bus
API of logind, see
org.freedesktop.login15.
The Manager Object
The main entry point object is available on the fixed
/org/freedesktop/systemd1 object path:
$ gdbus introspect --system \
--dest org.freedesktop.systemd1 \
--object-path /org/freedesktop/systemd1
node /org/freedesktop/systemd1 {
interface org.freedesktop.systemd1.Manager {
methods:
GetUnit(in s name,
out o unit);
GetUnitByPID(in u pid,
out o unit);
LoadUnit(in s name,
out o unit);
StartUnit(in s name,
in s mode,
out o job);
StartUnitReplace(in s old_unit,
in s new_unit,
in s mode,
out o job);
StopUnit(in s name,
in s mode,
out o job);
ReloadUnit(in s name,
in s mode,
out o job);
RestartUnit(in s name,
in s mode,
out o job);
TryRestartUnit(in s name,
in s mode,
out o job);
ReloadOrRestartUnit(in s name,
in s mode,
out o job);
ReloadOrTryRestartUnit(in s name,
in s mode,
out o job);
KillUnit(in s name,
in s who,
in i signal);
ResetFailedUnit(in s name);
GetJob(in u id,
out o job);
CancelJob(in u id);
ClearJobs();
ResetFailed();
ListUnits(out a(ssssssouso) units);
ListJobs(out a(usssoo) jobs);
Subscribe();
Unsubscribe();
Reload();
Reexecute();
Exit();
Reboot();
PowerOff();
Halt();
KExec();
SwitchRoot(in s new_root,
in s init);
SetEnvironment(in as names);
UnsetEnvironment(in as names);
UnsetAndSetEnvironment(in as unset,
in as set);
ListUnitFiles(out a(ss) files);
GetUnitFileState(in s file,
out s state);
EnableUnitFiles(in as files,
in b runtime,
in b force,
out b carries_install_info,
out a(sss) changes);
DisableUnitFiles(in as files,
in b runtime,
out a(sss) changes);
ReenableUnitFiles(in as files,
in b runtime,
in b force,
out b carries_install_info,
out a(sss) changes);
LinkUnitFiles(in as files,
in b runtime,
in b force,
out a(sss) changes);
PresetUnitFiles(in as files,
in b runtime,
in b force,
out b carries_install_info,
out a(sss) changes);
MaskUnitFiles(in as files,
in b runtime,
in b force,
out a(sss) changes);
UnmaskUnitFiles(in as files,
in b runtime,
out a(sss) changes);
SetDefaultTarget(in as files,
out a(sss) changes);
GetDefaultTarget(out s name);
SetUnitProperties(in s name,
in b runtime,
in a(sv) properties);
StartTransientUnit(in s name,
in s mode,
in a(sv) properties,
in a(sa(sv)) aux,
out o job);
signals:
UnitNew(s id,
o unit);
UnitRemoved(s id,
o unit);
JobNew(u id,
o job,
s unit);
JobRemoved(u id,
o job,
s unit,
s result);
StartupFinished(t firmware,
t loader,
t kernel,
t initrd,
t userspace,
t total);
UnitFilesChanged();
Reloading(b active);
properties:
readonly s Version = 'systemd 205';
readonly s Features = '+PAM +LIBWRAP +AUDIT +SELINUX +IMA +SYSVINIT +LIBCRYPTSETUP +GCRYPT +ACL +XZ';
readonly s Tainted = '';
readonly t FirmwareTimestamp = 0;
readonly t FirmwareTimestampMonotonic = 0;
readonly t LoaderTimestamp = 0;
readonly t LoaderTimestampMonotonic = 0;
readonly t KernelTimestamp = 0;
readonly t KernelTimestampMonotonic = 0;
readonly t InitRDTimestamp = 0;
readonly t InitRDTimestampMonotonic = 0;
readonly t UserspaceTimestamp = 1373892700771932;
readonly t UserspaceTimestampMonotonic = 347348267507;
readonly t FinishTimestamp = 1373892717621078;
readonly t FinishTimestampMonotonic = 347365116654;
readonly t GeneratorsStartTimestamp = 1374345509428734;
readonly t GeneratorsStartTimestampMonotonic = 500549330609;
readonly t GeneratorsFinishTimestamp = 1374345509562375;
readonly t GeneratorsFinishTimestampMonotonic = 500549464250;
readonly t UnitsLoadStartTimestamp = 1374345509562782;
readonly t UnitsLoadStartTimestampMonotonic = 500549464657;
readonly t UnitsLoadFinishTimestamp = 1374345509652212;
readonly t UnitsLoadFinishTimestampMonotonic = 500549554088;
readonly t SecurityStartTimestamp = 1374345509562782;
readonly t SecurityStartTimestampMonotonic = 500549464657;
readonly t SecurityFinishTimestamp = 1374345509652212;
readonly t SecurityFinishTimestampMonotonic = 500549554088;
readwrite s LogLevel = 'info';
readwrite s LogTarget = 'journal';
readonly u NNames = 100;
readonly u NJobs = 0;
readonly u NInstalledJobs = 266;
readonly u NFailedJobs = 4;
readonly d Progress = 1.0;
readonly as Environment = ['PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin', 'LANG=C'];
readonly b ConfirmSpawn = false;
readonly b ShowStatus = true;
readonly as UnitPath = ['/etc/systemd/system', '/run/systemd/system', '/run/systemd/generator', '/usr/local/lib/systemd/system', '/usr/lib/systemd/system'];
readonly s DefaultStandardOutput = 'journal';
readonly s DefaultStandardError = 'inherit';
readwrite t RuntimeWatchdogUSec = 0;
readwrite t ShutdownWatchdogUSec = 600000000;
readonly s Virtualization = '';
readonly s Architecture = 'x86-64';
};
interface org.freedesktop.DBus.Properties {
...
};
interface org.freedesktop.DBus.Peer {
...
};
interface org.freedesktop.DBus.Introspectable {
...
};
};
Security
Read access is generally granted to all clients, but changes may only be made by privileged
clients. PolicyKit is not used by this service, and access is controlled exclusively via the D-Bus
policy.
Methods
Note that many of the calls exist twice: once on the Manager
object, and once on the respective unit objects. This is to optimize access times so that methods that
belong to unit objects do not have to be called with a resolved unit path, but can be called with only
the unit id, too.
GetUnit() may be used to get the unit object path for a unit name. It takes
the unit name and returns the object path. If a unit has not been loaded yet by this name this call
will fail.
GetUnitByPID() may be used to get the unit object path of the unit a process
ID belongs to. Takes a UNIX PID and returns the object path. The PID must refer to an existing process
of the system.
LoadUnit() is similar to GetUnit() but will load the
unit from disk if possible.
StartUnit() enqeues a start job, and possibly depending jobs. Takes the unit
to activate, plus a mode string. The mode needs to be one of replace,
fail, isolate, ignore-dependencies,
ignore-requirements. If replace the call will start the unit and
its dependencies, possibly replacing already queued jobs that conflict with this. If
fail the call will start the unit and its dependencies, but will fail if this would
change an already queued job. If isolate the call will start the unit in question
and terminate all units that aren't dependencies of it. If ignore-dependencies it
will start a unit but ignore all its dependencies. If ignore-requirements it will
start a unit but only ignore the requirement dependencies. It is not recommended to make use of the
latter two options. Returns the newly created job object.
StartUnitReplace() is similar to StartUnit() but
replaces a job that is queued for one unit by a job for another.
StopUnit() is similar to StartUnit() but stops the
specified unit rather than starting it. Note that isolate mode is invalid for this
call.
ReloadUnit(), RestartUnit(),
TryRestartUnit(), ReloadOrRestartUnit(),
ReloadOrTryRestartUnit() may be used to restart and/or reload a unit, and takes
similar arguments as StartUnit(). Reloading is done only if the unit is already
running and fails otherwise. If a service is restarted that isn't running it will be started, unless
the "Try" flavor is used in which case a service that isn't running is not affected by the restart. The
"ReloadOrRestart" flavors attempt a reload if the unit supports it and use a restart otherwise.
KillUnit() may be used to kill (i.e. send a signal to) all processes of a
unit. Takes the unit name, an enum who and a UNIX
signal number to send. The who enum is one of
main, control or all. If
main, only the main process of a unit is killed. If control only
the control process of the unit is killed, if all all processes are killed. A
control process is for example a process that is configured via
ExecStop= and is spawned in parallel to the main daemon process, in order to shut it
down.
GetJob() returns the job object path for a specific job, identified by its
id.
CancelJob() cancels a specific job identified by its numer ID. This
operation is also available in the Cancel() method of Job objects (see below), and
exists primarily to reduce the necessary round trips to execute this operation. Note that this will not
have any effect on jobs whose execution has already begun.
ClearJobs() flushes the job queue, removing all jobs that are still
queued. Note that this does not have any effect on jobs whose execution has already begun, it only
flushes jobs that are queued and have not yet begun execution.
ResetFailedUnit() resets the "failed" state of a specific unit.
ResetFailed() resets the "failed" state of all units.
ListUnits() returns an array with all currently loaded units. Note that
units may be known by multiple names at the same name, and hence there might be more unit names loaded
than actual units behind them. The array consists of structures with the following elements:
The primary unit name as string
The human readable description string
The load state (i.e. whether the unit file has been loaded
successfully)
The active state (i.e. whether the unit is currently started or
not)
The sub state (a more fine-grained version of the active state that is specific to
the unit type, which the active state is not)
A unit that is being followed in its state by this unit, if there is any, otherwise
the empty string.
The unit object path
If there is a job queued for the job unit the numeric job id, 0
otherwise
The job type as string
The job object path
ListJobs() returns an array with all currently queued jobs. Returns an array
consisting of structures with the following elements:
The numeric job id
The primary unit name for this job
The job type as string
The job state as string
The job object path
The unit object path
Subscribe() enables most bus signals to be sent out. Clients which are
interested in signals need to call this function. Signals are only sent out if at least one client
invoked this function. Unsubscribe() undoes the signal subscription that
Subscribe() implements. It is not necessary to invoke
Unsubscribe() as clients are tracked. Signals are no longer sent out as soon as
all clients which previously asked for Subscribe() either closed the bus
connection or invoked Unsubscribe().
Reload() may be invoked to reload all unit files.
Reexecute() may be invoked to reexecute the main manager process. It will
serialize its state, reexecute, and deserizalize the state again. This is useful for upgrades and is a
more comprehensive version of Reload().
Exit() may be invoked to ask the manager to exit. This is not available for
the system manager and is useful only for user session managers.
Reboot(), PowerOff(), Halt(),
KExec() may be used to ask for immediate reboot, powering down, halt or kexec
based reboot of the system. Note that this does not shut down any services and immediately transitions
into the reboot process. These functions are normally only called as last step of shutdown, and should
not be called directly. To shut down the machine it is a much better choice generally to invoke
Reboot() and PoweOff() on the
systemd-logind manager object; see
org.freedesktop.login15
for more information.
SwitchRoot() may be used to transition to a new root directory. This is
intended to be used by initial RAM disks. The call takes two arguments: the new root directory (which
needs to be specified), plus an init binary path (which may be left empty, in which case it is
automatically searched for). The state of the system manager will be serialized before the
transition. After the transition the manager binary on the main system is invoked and replaces the old
PID 1. All state will then be deserialized.
SetEnvironment() may be used to alter the environment block that is passed
to all spawned processes. Takes a string array with environment variable assignments. Settings passed
will override previously set variables.
UnsetEnvironment() may be used to unset environment variables. Takes a
string array with environment variable names. All variables specified will be unset (if they have been
set previously) and no longer be passed to all spawned processes. This call has no effect for variables
that were previously not set, but will not fail in that case.
UnsetAndSetEnvironment() is a combination of
UnsetEnvironment() and SetEnvironment(). It takes two
lists. The first one is a list of variables to unset, the second one of assignments to set. If a
variable is listed in both, the variable is set after this call, i.e. the set list overrides the unset
list.
ListUnitFiles() returns an array of unit names plus their enablement
status. Note that ListUnit() returns a list of units currently loaded into memory,
while ListUnitFiles() returns a list of unit files that could
be found on disk. Note that while most units are read directly from a unit file with the same name some
units are not backed by files, and some files (templates) cannot directly be loaded as units but need
to be instantiated.
GetUnitFileState() returns the current enablement status of specific unit
file.
EnableUnitFiles() may be used to enable one or more units in the system (by
creating symlinks to them in /etc or /run). It takes a list
of unit files to enable (either just file names or full absolute paths if the unit files are residing
outside the usual unit search paths), and two booleans: the first controls whether the unit shall be
enabled for runtime only (true, /run), or persistently (false,
/etc). The second one controls whether symlinks pointing to other units shall be
replaced if necessary. This call returns one boolean and an array with the changes made. The boolean
signals whether the unit files contained any enablement information (i.e. an [Install]) section. The
changes list consists of structures with three strings: the type of the change (one of
symlink or unlink), the file name of the symlink and the
destination of the symlink. Note that most of the following calls return a changes list in the same
format.
Similarly, DisableUnitFiles() disables one or more units in the system,
i.e. removes all symlinks to them in /etc and /run.
Similarly, ReenableUnitFiles() applies the changes to one or more units that
would result from disabling and enabling the unit quickly one after the other in an atomic
fashion. This is useful to apply updated [Install] information contained in unit files.
Similarly, LinkUnitFiles() links unit files (that are located outside of the
usual unit search paths) into the unit search path.
Similarly, PresetUnitFiles() enables/disables one or more units file
according to the preset policy. See
systemd.preset7 for more
information.
Similarly, MaskUnitFiles() masks unit files, and
UnmaskUnitFiles() unmasks them again.
SetDefaultTarget() changes the default.target link. See
bootup7 for more
information
GetDefaultTarget() retrieves the name of the unit to which
default.target is aliased
SetUnitProperties() may be used to modify certain unit properties at
runtime. Not all properties may be changed at runtime, but many resource management settings (primarily
those listed in
systemd.cgroup5)
may. The changes are applied instantly, and stored on disk for future boots, unless
runtime is true, in which case the settings only apply until the next
reboot. name is the name of the unit to modify. properties are
the settings to set, encoded as an array of property name and value pairs. Note that this is not a
dictionary! Note that when setting array properties with this call this usually results in appending to
the pre-configured array. To reset the configured arrays set the property to an empty array first, then
append to it.
StartTransientUnit() may be used to create and start a transient unit, which
will be released as soon as it is not running or referenced anymore or the system is
rebooted. name is the unit name including suffix, and must be
unique. mode is the same as in StartUnit(),
properties contains properties of the unit, specified like in
SetUnitProperties(). aux is currently unused and should be
passed as empty array. See the New Control Group
Interface for more information how to make use of this functionality for resource control
purposes.
Signals
Note that most signals are sent out only after Subscribe() has been invoked
by at least one client. Make sure to invoke this call when subscribing to these signals!
UnitNew() and UnitRemoved() are sent out each time a
new unit is loaded or unloaded. Note that this has little to do with whether a unit is available on
disk or not, and simply reflects the units that are currently loaded into memory. The signals take two
parameters: the primary unit name and the object path.
JobNew() and JobRemoved() are sent out each time a new
job is queued or dequeued. Both signals take the numeric job ID, the bus path and the primary unit name
for this job as argument. JobRemoved() also includes a result string, being one of
done, canceled, timeout,
failed, dependency,
skipped. done indicates successful execution of a
job. canceled indicates that a job has been canceled (via
CancelJob() above) before it finished execution (this doesn't necessarily mean
though that the job operation is actually cancelled too, see above). timeout
indicates that the job timeout was reached. failed indicates that the job
failed. dependency indicates that a job this job has been depending on failed and
the job hence has been removed too. skipped indicates that a job was skipped because
it didn't apply to the units current state.
StartupFinished() is sent out when startup finished. It carries six
microsecond timespan values each indicating how much boot time has been spent in the firmware (if
known), in the boot loader (if known), in the kernel initialization phase, in the initrd (if known), in
userspace and in total. These values may also be calculated from the
FirmwareTimestampMonotonic, LoaderTimestampMonotonic,
InitRDTimestampMonotonic, UserspaceTimestampMonotonic,
FinishTimestampMonotonic properties (see below).
UnitFilesChanged() is sent out each time the list of enabled or masked unit
files on disk have changed.
Reloading() is sent out immediately before a daemon reload is done (with the
boolean parameter set to True) and after a daemon reload is completed (with the boolean parameter set
to False). This may be used by UIs to optimize UI updates
Properties
Most properties simply reflect the respective options in
/etc/systemd/system.conf and the kernel command line.
The others:
Version encodes the version string of the running systemd instance. Note that
the version string is purely informational, it should not be parsed, one may not assume the version to
be formatted in any particular way. We take the liberty to change the versioning scheme at any time and
it is not part of the API.
Features encodes the features that have been enabled and disabled for this
build. Enabled options are prefixed with +, disabled options with -.
Tainted encodes a couple of taint flags, as a colon-separated list. When
systemd detects it is run on a system with certain problems it will set an appropriate taint
flag. Taints may be used to lower the chance of bogus bug reports. The following taints are currently
known: split-usr, mtab-not-symlink,
cgroups-missing, local-hwclock. split-usr is
set if /usr is not pre-mounted when systemd is first invoked. See
Booting Without /usr is Broken
for details why this is bad. mtab-not-symlink indicates that
/etc/mtab is not a symlink to /proc/self/mounts as
required. cgroups-missing indicates that control groups have not been enabled in the
kernel. local-hwclock indicates that the local RTC is configured to be in local time
rather than UTC.
FirmwareTimestamp, FirmwareTimestampMonotonic,
LoaderTimestamp, LoaderTimestampMonotonic,
KernelTimestamp, KernelTimestampMonotonic,
InitRDTimestamp, InitRDTimestampMonotonic,
UserspaceTimestamp, UserspaceTimestampMonotonic,
FinishTimestamp, FinishTimestampMonotonic encode
CLOCK_REALTIME and CLOCK_MONOTONIC microsecond timestamps
taken when the firmware first began execution, when the boot loader first began execution, when the
kernel first began execution, when the initrd first began execution, when the main systemd instance
began execution and finally, when all queued startup jobs finished execution. These values are useful
for determining boot-time performance. Note that as monotonic time begins with the kernel startup the
KernelTimestampMonotonic timestamp will always be 0, and FirmwareTimestampMonotonic and
LoaderTimestampMonotonic are to be read as negative values. Also, not all fields are available,
depending on the used firmware, boot loader or initrd implementation. In these cases the respective
pairs of timestamps are both 0, indicating that no data is available.
Similarly, the SecurityStartTimestamp,
GeneratorsStartTimestamp and LoadUnitTimestamp (plus their
monotonic and stop counterparts) expose performance data for uploading the security policies to the
kernel (such as the SELinux, IMA, or SMACK policies), for running the generator tools and for loading
the unit files
NNames encodes how many unit names are currently known. This only includes
names of units that are currently loaded and can be more than actually loaded units since units may
have more than one name.
NJobs encodes how many jobs are currently queued.
NInstalledJobs encodes how many jobs have ever been queued in total.
NFailedJobs encodes how many jobs have ever failed in total.
Progress encodes boot progress as floating point value between 0.0 and
1.0. This value begins at 0.0 at early-boot and ends at 1.0 when boot is finished and is based on the
number of executed and queued jobs. After startup this field is always 1.0 indicating a finished
boot.
Environment encodes the environment block passed to all executed services. It
may be altered with bus calls such as SetEnvironment() (see above).
UnitPath encodes the currently active unit file search path. It is an array of
strings, each being one file system path
Virtualization contains a short ID string describing the virtualization
technology the system runs in. On bare-metal hardware this is the empty string, otherwise an identifier
such as kvm, vmware and so on. For a full list of IDs see
systemd-detect-virt1.
Note that only the "innermost" virtualization technology is exported here. This detects both
full-machine virtualizations (VMs) and shared-kernel virtualization (containers).
Architecture contains a short ID string describing the architecture the
systemd instance is running on. This follows the same vocabulary as
ConditionArchitectures=.
ControlGroup contains the root control group path of this system manager. Note
that the root path is encoded as empty string here (not as /!), so that it can be
appended to /sys/fs/cgroup/systemd easily. This value will be set to the empty
string for the host instance, and some other string for container instances
Unit Objects
$ gdbus introspect --system --dest org.freedesktop.systemd1 \
--object-path /org/freedesktop/systemd1/unit/avahi_2ddaemon_2eservice
node /org/freedesktop/systemd1/unit/avahi_2ddaemon_2eservice {
interface org.freedesktop.systemd1.Unit {
methods:
Start(in s mode,
out o job);
Stop(in s mode,
out o job);
Reload(in s mode,
out o job);
Restart(in s mode,
out o job);
TryRestart(in s mode,
out o job);
ReloadOrRestart(in s mode,
out o job);
ReloadOrTryRestart(in s mode,
out o job);
Kill(in s who,
in i signal);
ResetFailed();
SetProperties(in b runtime,
in a(sv) properties);
signals:
properties:
readonly s Id = 'avahi-daemon.service';
readonly as Names = ['avahi-daemon.service'];
readonly s Following = '';
readonly as Requires = ['avahi-daemon.socket', 'dbus.socket', 'basic.target'];
readonly as RequiresOverridable = [];
readonly as Requisite = [];
readonly as RequisiteOverridable = [];
readonly as Wants = [];
readonly as BindsTo = [];
readonly as PartOf = [];
readonly as RequiredBy = [];
readonly as RequiredByOverridable = [];
readonly as WantedBy = ['multi-user.target'];
readonly as BoundBy = [];
readonly as ConsistsOf = [];
readonly as Conflicts = ['shutdown.target'];
readonly as ConflictedBy = [];
readonly as Before = ['shutdown.target', 'multi-user.target'];
readonly as After = ['avahi-daemon.socket', 'systemd-journald.socket', 'dbus.socket', 'basic.target'];
readonly as OnFailure = [];
readonly as Triggers = [];
readonly as TriggeredBy = ['avahi-daemon.socket'];
readonly as PropagatesReloadTo = [];
readonly as ReloadPropagatedFrom = [];
readonly as RequiresMountsFor = [];
readonly s Description = 'Avahi mDNS/DNS-SD Stack';
readonly s SourcePath = '';
readonly as DropInPaths = [];
readonly as Documentation = [];
readonly s LoadState = 'loaded';
readonly s ActiveState = 'active';
readonly s SubState = 'running';
readonly s FragmentPath = '/usr/lib/systemd/system/avahi-daemon.service';
readonly s UnitFileState = 'enabled';
readonly t InactiveExitTimestamp = 1368576738559539;
readonly t InactiveExitTimestampMonotonic = 22561234;
readonly t ActiveEnterTimestamp = 1368576738648314;
readonly t ActiveEnterTimestampMonotonic = 22650009;
readonly t ActiveExitTimestamp = 0;
readonly t ActiveExitTimestampMonotonic = 0;
readonly t InactiveEnterTimestamp = 0;
readonly t InactiveEnterTimestampMonotonic = 0;
readonly b CanStart = true;
readonly b CanStop = true;
readonly b CanReload = true;
readonly b CanIsolate = false;
readonly (uo) Job = (0, '/org/freedesktop/systemd1/unit/avahi_2ddaemon_2eservice');
readonly b StopWhenUnneeded = false;
readonly b RefuseManualStart = false;
readonly b RefuseManualStop = false;
readonly b AllowIsolate = false;
readonly b DefaultDependencies = true;
readonly b OnFailureIsolate = false;
readonly b IgnoreOnIsolate = false;
readonly b IgnoreOnSnapshot = false;
readonly b NeedDaemonReload = false;
readonly t JobTimeoutUSec = 0;
readonly t ConditionTimestamp = 1368576738557978;
readonly t ConditionTimestampMonotonic = 22559674;
readonly b ConditionResult = true;
readonly a(sbbsi) Conditions = [('ConditionVirtualization, false, false, 'no', 1)];
readonly (ss) LoadError = ('', '');
readonly b Transient = false;
};
interface org.freedesktop.systemd1.Service {
...
};
interface org.freedesktop.DBus.Properties {
...
};
interface org.freedesktop.DBus.Peer {
...
};
interface org.freedesktop.DBus.Introspectable {
...
};
};
Methods
Start(), Stop(), Reload(),
Restart(), TryRestart(),
ReloadOrRestart(), ReloadOrTryRestart(),
Kill(), ResetFailed(), and
SetProperties() implement the same operation as the respective method calls on the
Manager object (see above), however operate on the unit object and hence
do not take a unit name parameter. Invoking the methods directly on the Manager object has the
advantage of not requiring a GetUnit() call to get the unit object for a specific
unit name. Calling the methods on the Manager object is hence a round trip optimization.
Properties
Id contains the primary name of the unit.
Names contains all names of the unit, including the primary name that is also
exposed in Id.
Following either contains the empty string or contains the name of another
unit that this unit follows in state. This is used for some device units which reflect the unit state
machine of another unit, and which other unit this is might possibly change.
Requires, RequiresOverridable,
Requisite, RequisiteOverridable, Wants,
BindsTo, RequiredBy, RequiredByOverridable,
WantedBy, BoundBy, Conflicts,
ConflictedBy, Before, After,
OnFailure, Triggers, TriggeredBy,
PropagatesReloadTo, RequiresMountsFor contain arrays which encode
the dependencies and their inverse dependencies (where this applies), as configured in the unit file or
determined automatically.
Description contains the human readable description string for the
unit.
SourcePath contains the path to a configuration file this unit is
automatically generated from in case it is not a native unit (in which case it contains the empty
string). For example, all mount units generated from /etc/fstab have this field
set to this value.
Documentation contains a string array with URLs of documentation for this
unit.
LoadState contains a state value that reflects whether the configuration file
of this unit has been loaded. The following states are currently defined: loaded,
error, masked. loaded indicates that the
configuration was successfully loaded. error indicates that the configuration failed
to load, the LoadError field (see below) contains information about the cause of
this failure. masked indicates that the unit is currently masked out (i.e. symlinked
to /dev/null or empty). Note that the LoadState is fully
orthogonal to the ActiveState (see below) as units without valid loaded
configuration might be active (because configuration might have been reloaded at a time where a unit
was already active).
ActiveState contains a state value that reflects whether the unit is currently
active or not. The following states are currently defined: active,
reloading, inactive, failed,
activating, deactivating. active indicates
that unit is active (obviously...). reloading indicates that the unit is active and
currently reloading its configuration. inactive indicates that it is inactive and
the previous run was successful or no previous run has taken place yet. failed
indicates that it is inactive and the previous run was not successful (more information about the
reason for this is available on the unit type specific interfaces, for example for services in the
Result property, see below). activating indicates that the unit
has previously been inactive but is currently in the process of entering an active state. Conversely
deactivating indicates that the unit is currently in the process of
deactivation.
SubState encodes states of the same state machine that
ActiveState covers, but knows more fine-grained states that are
unit-type-specific. Where ActiveState only covers six high-level states,
SubState covers possibly many more low-level unit-type-specific states that are
mapped to the six high-level states. Note that multiple low-level states might map to the same
high-level state, but not vice versa. Not all high-level states have low-level counterparts on all unit
types. At this point the low-level states are not documented here, and are more likely to be extended
later on than the common high-level states explained above.
FragmentPath contains the unit file path this unit was read from, if there is
any (if not this contains the empty string).
UnitFileState encodes the install state of the unit file of
FragmentPath. It currently knows the following states: enabled,
enabled-runtime, linked, linked-runtime,
masked, masked-runtime, static,
disabled, invalid. enabled indicates that a
unit file is permanently enabled. enable-runtime indicates the unit file is only
temporarily enabled, and will no longer be enabled after a reboot (that means, it is enabled via
/run symlinks, rather than /etc). linked
indicates that a unit is linked into /etc permanently, linked
indicates that a unit is linked into /run temporarily (until the next
reboot). masked indicates that the unit file is masked permanently,
masked-runtime indicates that it is only temporarily masked in
/run, until the next reboot. static indicates that the unit is
statically enabled, i.e. always enabled and doesn't need to be enabled
explicitly. invalid indicates that it could not be determined whether the unit file
is enabled.
InactiveExitTimestamp, InactiveExitTimestampMonotonic,
ActiveEnterTimestamp, ActiveEnterTimestampMonotonic,
ActiveExitTimestamp, ActiveExitTimestampMonotonic,
InactiveEnterTimestamp, InactiveEnterTimestampMonotonic contain
CLOCK_REALTIME and CLOCK_MONOTONIC 64-bit microsecond
timestamps of the last time a unit left the inactive state, entered the active state, exited the active
state, or entered an inactive state. These are the points in time where the unit transitioned
inactive/failed → activating,
activating → active, active →
deactivating, and finally deactivating →
inactive/failed. The fields are 0 in case such a transition has
not been recording on this boot yet.
CanStart, CanStop, CanReload encodes as
booleans whether the unit supports the start, stop or reload operations. Even if a unit supports such
an operation the client might not necessary have the right privileges to execute them.
CanIsolate encodes as boolean whether the unit may be started in isolation
mode.
Job encodes the job ID and job object path of the job currently scheduled or
executed for this unit, if there is any. If no job is scheduled or executed the job id field will be
0.
StopWhenUnneeded, RefuseManualStart,
RefuseManualStop, AllowIsolate,
DefaultDependencies, OnFailureIsolate,
IgnoreOnIsolate, IgnoreOnSnapshot map directly to the
corresponding configuration booleans in the unit file.
DefaultControlGroup contains the main control group of this unit as a
string. This refers to a group in systemd's own name=systemd hierarchy, which
systemd uses to watch and manipulate the unit and all its processes.
NeedDaemonReload is a boolean that indicates whether the configuration file
this unit is loaded from (i.e. FragmentPath or SourcePath) has
changed since the configuration was read and hence whether a configuration reload is
recommended.
JobTimeoutUSec maps directly to the corresponding configuration setting in the
unit file.
ConditionTimestamp and ConditionTimestampMonotonic contain
the CLOCK_REALTIME/CLOCK_MONOTONIC microsecond timestamps of
the last time the configured conditions of the unit have been checked, or 0 if they have never been
checked. Conditions are checked when a unit is requested to start.
ConditionResult contains the condition result of the last time the configured
conditions of this unit were checked.
Conditions contains all configured conditions of the unit. For each condition
five fields are given: condition type (e.g. ConditionPathExists), whether the
condition is a trigger condition, whether the condition is reversed, the right hand side of the
condtion (e.g. the path in case of ConditionPathExists), and the status. The status
can be 0, in which case the condition hasn't been checked yet, a positive value, in which case the
condition passed, or a negative value, in which case the condition failed. Currently only 0, +1, and -1
are used, but additional values may be used in the future, retaining the meaning of
zero/positive/negative values
LoadError contains a pair of strings. If the unit failed to load (as encoded
in LoadState, see above), then this will include a D-Bus error pair consisting of
the error ID and an explanatory human readable string of what happened. If it succeeded to load this
will be a pair of empty strings.
Transient contains a boolean that indicates whether the unit was created as
transient unit (i.e. via CreateTransientUnit() on the manager object)
Service Unit Objects
All service unit objects implement the
org.freedesktop.systemd1.Service interface (described here) in addition to
the generic org.freedesktop.systemd1.Unit interface (see above).
$ gdbus introspect --system --dest org.freedesktop.systemd1 \
--object-path /org/freedesktop/systemd1/unit/avahi_2ddaemon_2eservice
interface org.freedesktop.systemd1.Unit {
...
};
interface org.freedesktop.systemd1.Service {
methods:
signals:
properties:
readonly s Type = 'dbus';
readonly s Restart = 'no';
readonly s PIDFile = '';
readonly s NotifyAccess = 'main';
readonly t RestartUSec = 100000;
readonly t TimeoutUSec = 90000000;
readonly t WatchdogUSec = 0;
readonly t WatchdogTimestamp = 0;
readonly t WatchdogTimestampMonotonic = 0;
readonly t StartLimitInterval = 10000000;
readonly u StartLimitBurst = 5;
readwrite s StartLimitAction = 'none
readonly s Slice = 'system.slice';
readonly s ControlGroup = '/system.slice/avahi-daemon.service';
readonly a(sasbttuii) ExecStartPre = [];
readonly a(sasbttuii) ExecStart = [('/usr/sbin/avahi-daemon', ['/usr/sbin/avahi-daemon', '-s'], false, 0, 0, 0, 0, 0, 0, 0)];
readonly a(sasbttuii) ExecStartPost = [];
readonly a(sasbttuii) ExecReload = [('/usr/sbin/avahi-daemon', ['/usr/sbin/avahi-daemon', '-r'], false, 0, 0, 0, 0, 0, 0, 0)];
readonly a(sasbttuii) ExecStop = [];
readonly a(sasbttuii) ExecStopPost = [];
readonly as Environment = [];
readonly a(sb) EnvironmentFiles = [];
readonly u UMask = 18;
readonly t LimitCPU = 18446744073709551615;
readonly t LimitFSIZE = 18446744073709551615;
readonly t LimitDATA = 18446744073709551615;
readonly t LimitSTACK = 18446744073709551615;
readonly t LimitCORE = 18446744073709551615;
readonly t LimitRSS = 18446744073709551615;
readonly t LimitNOFILE = 4096;
readonly t LimitAS = 18446744073709551615;
readonly t LimitNPROC = 256963;
readonly t LimitMEMLOCK = 65536;
readonly t LimitLOCKS = 18446744073709551615;
readonly t LimitSIGPENDING = 256963;
readonly t LimitMSGQUEUE = 819200;
readonly t LimitNICE = 0;
readonly t LimitRTPRIO = 0;
readonly t LimitRTTIME = 18446744073709551615;
readonly s WorkingDirectory = '';
readonly s RootDirectory = '';
readonly i OOMScoreAdjust = 0;
readonly i Nice = 0;
readonly i IOScheduling = 0;
readonly i CPUSchedulingPolicy = 0;
readonly i CPUSchedulingPriority = 0;
readonly ay CPUAffinity = [];
readonly t TimerSlackNSec = 50000;
readonly b CPUSchedulingResetOnFork = false;
readonly b NonBlocking = false;
readonly s StandardInput = 'null';
readonly s StandardOutput = 'journal';
readonly s StandardError = 'inherit';
readonly s TTYPath = '';
readonly b TTYReset = false;
readonly b TTYVHangup = false;
readonly b TTYVTDisallocate = false;
readonly i SyslogPriority = 30;
readonly s SyslogIdentifier = '';
readonly b SyslogLevelPrefix = true;
readonly s Capabilities = '';
readonly i SecureBits = 0;
readonly t CapabilityBoundingSet = 18446744073709551615;
readonly s User = '';
readonly s Group = '';
readonly as SupplementaryGroups = [];
readonly s TCPWrapName = '';
readonly s PAMName = '';
readonly as ReadWriteDirectories = [];
readonly as ReadOnlyDirectories = [];
readonly as InaccessibleDirectories = [];
readonly t MountFlags = 0;
readonly b PrivateTmp = false;
readonly b PrivateNetwork = false;
readonly b SameProcessGroup = false;
readonly s UtmpIdentifier = '';
readonly b IgnoreSIGPIPE = true;
readonly b NoNewPrivileges = false;
readonly au SystemCallFilter = [];
readonly s KillMode = 'control-group';
readonly i KillSignal = 15;
readonly b SendSIGKILL = true;
readonly b SendSIGHUP = false;
readonly b CPUAccounting = false;
readonly t CPUShares = 1024;
readonly b BlockIOAccounting = false;
readonly t BlockIOWeight = 1000;
readonly a(st) BlockIODeviceWeight = [];
readonly a(st) BlockIOReadBandwidth=;
readonly a(st) BlockIOWriteBandwidth=;
readonly b MemoryAccounting = false;
readonly t MemoryLimit = 18446744073709551615;
readonly s DevicePolicy = 'auto';
readonly a(ss) DeviceAllow = [];
readonly b PermissionsStartOnly = false;
readonly b RootDirectoryStartOnly = false;
readonly b RemainAfterExit = false;
readonly t ExecMainStartTimestamp = 1368576738559537;
readonly t ExecMainStartTimestampMonotonic = 22561233;
readonly t ExecMainExitTimestamp = 1368576738559537;
readonly t ExecMainExitTimestampMonotonic = 22561233;
readonly u ExecMainPID = 666;
readonly i ExecMainCode = 0;
readonly i ExecMainStatus = 0;
readonly u MainPID = 666;
readonly u ControlPID = 0;
readonly s BusName = 'org.freedesktop.Avahi';
readonly s StatusText = 'Server startup complete. Host name is fedora.local. Local service cookie is 2431121142.';
readonly s Result = 'success';
};
interface org.freedesktop.DBus.Properties {
...
};
interface org.freedesktop.DBus.Peer {
...
};
interface org.freedesktop.DBus.Introspectable {
...
};
};
Properties
Most properties of the Service interface map directly to the corresponding settings in service
unit files. For the sake of brevity, here's a list of all exceptions only:
WatchdogTimestamp and WatchdogTimestampMonotonic contain
CLOCK_REALTIME/CLOCK_MONOTONIC microsecond timestamps of the
last watchdog ping received from the service, or 0 if none was ever received.
ExecStartPre, ExecStart, ExecStartPost,
ExecReload, ExecStop, ExecStop each are arrays
of structures each containing: the binary path to execute; an array with all arguments to pass to the
executed command, starting with argument 0; a boolean whether it should be considered a failure if the
process exits uncleanly; two pairs of
CLOCK_REALTIME/CLOCK_MONOTONIC microsecond timestamps when
the process began and finished running the last time, or 0 if it never ran or never finished running;
the PID of the process, or 0 if it has not run yet; the exit code and status of the last run. This
field hence maps more or less to the corresponding setting in the service unit file but is augmented
with runtime data.
LimitCPU (and related properties) map more or less directly to the
corresponding settings in the service unit files, however are set to 18446744073709551615 (i.e. -1) if
they aren't set.
Capabilities contains the configured capabilities, as formatted with
cap_to_text3.
SecureBits, CapabilityBoundingSet,
MountFlags also correspond to the configured settings of the unit files, but are
encoded as the actual binary flag fields they are, rather than formatted as string.
ExecMainStartTimestamp, ExecMainStartTimestampMonotonic,
ExecMainExitTimestamp, ExecMainExitTimestampMonotonic,
ExecMainPID, ExecMainCode, ExecMainStatus
contain information about the main process of the service as far as it is known. This is often the same
runtime information that is stored in ExecStart. However, it deviates for
Type=forking services where the main process of the service is not forked off
systemd directly. These fields either contain information of the last run of the process or of the
current running process.
MainPID and ControlPID contain the main and control PID of
the service. The main PID is the current main PID of the service and is 0 when the service currently
has no main PID. The control PID is the PID of the current start/stop/reload process running and is 0
if no such process is currently running. That means that ExecMainPID and
MainPID differ in the way that the latter immediately reflects whether a main
process is currently running while the latter possible contains information collected from the last run
even if the process is no longer around.
StatusText contains the status text passed to the service manager via a call
to
sd_notify3.
This may be used by services to inform the service manager about its internal state with a nice
explanatory string.
Result encodes the execution result of the last run of the service. It is
useful to determine the reason a service failed if it is in failed state (see
ActiveState above). The following values are currently known:
success is set if the unit didn't fail. resources indicates that
not enough resources have been available to fork off and execute the service
processes. timeout indicates that a time-out occurred while executing a service
operation. exit-code indicates that a service process exited with an unclean exit
code. signal indicates that a service process exited with an uncaught
signal. core-dump indicates that a service process exited uncleanly and dumped
core. watchdog indicates that a service did not send out watchdog ping messages
often enough. start-limit indicates that a service has been started too frequently
in a time frame (as configured in StartLimitInterval,
StartLimitBurst).
ControlGroup indicates the control group path the processes of this service
unit are placed in.
Socket Unit Objects
$ gdbus introspect --system --dest org.freedesktop.systemd1 \
--object-path /org/freedesktop/systemd1/unit/avahi_2ddaemon_2esocket
node /org/freedesktop/systemd1/unit/avahi_2ddaemon_2esocket {
interface org.freedesktop.systemd1.Unit {
...
};
interface org.freedesktop.systemd1.Socket {
methods:
signals:
properties:
readonly b BindIPv6Only = 'default';
readonly u Backlog = 128;
readonly t TimeoutUSec = 90000000;
readonly s Slice = 'system.slice';
readonly s ControlGroup = '/system.slice/avahi-daemon.socket';
readonly a(sasbttuii) ExecStartPre = [];
readonly a(sasbttuii) ExecStartPost = [];
readonly a(sasbttuii) ExecStopPre = [];
readonly a(sasbttuii) ExecStopPost = [];
readonly as Environment = [];
readonly a(sb) EnvironmentFiles = [];
readonly u UMask = 18;
readonly t LimitCPU = 18446744073709551615;
readonly t LimitFSIZE = 18446744073709551615;
readonly t LimitDATA = 18446744073709551615;
readonly t LimitSTACK = 18446744073709551615;
readonly t LimitCORE = 18446744073709551615;
readonly t LimitRSS = 18446744073709551615;
readonly t LimitNOFILE = 4096;
readonly t LimitAS = 18446744073709551615;
readonly t LimitNPROC = 61434;
readonly t LimitMEMLOCK = 65536;
readonly t LimitLOCKS = 18446744073709551615;
readonly t LimitSIGPENDING = 61434;
readonly t LimitMSGQUEUE = 819200;
readonly t LimitNICE = 0;
readonly t LimitRTPRIO = 0;
readonly t LimitRTTIME = 18446744073709551615;
readonly s WorkingDirectory = '';
readonly s RootDirectory = '';
readonly i OOMScoreAdjust = 0;
readonly i Nice = 0;
readonly i IOScheduling = 0;
readonly i CPUSchedulingPolicy = 0;
readonly i CPUSchedulingPriority = 0;
readonly ay CPUAffinity = [];
readonly t TimerSlackNSec = 50000;
readonly b CPUSchedulingResetOnFork = false;
readonly b NonBlocking = false;
readonly s StandardInput = 'null';
readonly s StandardOutput = 'journal';
readonly s StandardError = 'inherit';
readonly s TTYPath = '';
readonly b TTYReset = false;
readonly b TTYVHangup = false;
readonly b TTYVTDisallocate = false;
readonly i SyslogPriority = 30;
readonly s SyslogIdentifier = '';
readonly b SyslogLevelPrefix = true;
readonly s Capabilities = '';
readonly i SecureBits = 0;
readonly t CapabilityBoundingSet = 18446744073709551615;
readonly s User = '';
readonly s Group = '';
readonly as SupplementaryGroups = [];
readonly s TCPWrapName = '';
readonly s PAMName = '';
readonly as ReadWriteDirectories = [];
readonly as ReadOnlyDirectories = [];
readonly as InaccessibleDirectories = [];
readonly t MountFlags = 0;
readonly b PrivateTmp = false;
readonly b PrivateNetwork = false;
readonly b SameProcessGroup = false;
readonly s UtmpIdentifier = '';
readonly b IgnoreSIGPIPE = true;
readonly b NoNewPrivileges = false;
readonly au SystemCallFilter = [];
readonly s KillMode = 'control-group';
readonly i KillSignal = 15;
readonly b SendSIGKILL = true;
readonly b SendSIGHUP = false;
readonly b CPUAccounting = false;
readonly t CPUShares = 1024;
readonly b BlockIOAccounting = false;
readonly t BlockIOWeight = 1000;
readonly a(st) BlockIODeviceWeight = [];
readonly a(st) BlockIOReadBandwidth=;
readonly a(st) BlockIOWriteBandwidth=;
readonly b MemoryAccounting = false;
readonly t MemoryLimit = 18446744073709551615;
readonly s DevicePolicy = 'auto';
readonly a(ss) DeviceAllow = [];
readonly u ControlPID = 0;
readonly s BindToDevice = '';
readonly u DirectoryMode = 493;
readonly u SocketMode = 438;
readonly b Accept = false;
readonly b KeepAlive = false;
readonly i Priority = -1;
readonly t ReceiveBuffer = 0;
readonly t SendBuffer = 0;
readonly i IPTOS = -1;
readonly i IPTTL = -1;
readonly t PipeSize = 0;
readonly b FreeBind = false;
readonly b Transparent = false;
readonly b Broadcast = false;
readonly b PassCredentials = false;
readonly b PassSecurity = false;
readonly i Mark = -1;
readonly u MaxConnections = 64;
readonly u NAccepted = 0;
readonly u NConnections = 0;
readonly x MessageQueueMaxMessages = 0;
readonly x MessageQueueMessageSize = 0;
readonly a(ss) Listen = [('Stream', '/var/run/avahi-daemon/socket')];
readonly s Result = 'success';
readonly b ReusePort = false;
readonly s SmackLabel = '';
readonly s SmackLabelIPIn = '';
readonly s SmackLabelIPOut = '';
};
interface org.freedesktop.DBus.Properties {
...
};
interface org.freedesktop.DBus.Peer {
...
};
interface org.freedesktop.DBus.Introspectable {
...
};
};
Properties
Most of the properties map directly to the corresponding settings in socket unit files. As socket
units can include ExecStartPre (and similar) fields which contain information about
processes to execute. They also share most of the fields related to the execution context that Service
objects expose (see above).
In addition to these properties there are the following:
NAccepted contains the accumulated number of connections ever accepted on this
socket. This only applies to sockets with Accept set to true,
i.e. those where systemd is responsible for accepted connections.
Similarly NConnections contains the number of currently open connections on
this socket, and also applies only to socket with Accept set to
true.
Result encodes the reason why a socket unit failed if it is in
failed state (see ActiveState above). The values
success, resources, timeout,
exit-code, signal and core-dump have the same
meaning as they have for the corresponding field of service units (see above). In addition to that the
value service-failed-permanent indicates that the service of this socket failed
continuously.
Target Unit Objects
$ gdbus introspect --system --dest org.freedesktop.systemd1 \
--object-path /org/freedesktop/systemd1/unit/basic_2etarget
node /org/freedesktop/systemd1/unit/basic_2etarget {
interface org.freedesktop.systemd1.Unit {
...
};
interface org.freedesktop.systemd1.Target {
methods:
signals:
properties:
};
interface org.freedesktop.DBus.Properties {
...
};
interface org.freedesktop.DBus.Peer {
...
};
interface org.freedesktop.DBus.Introspectable {
...
};
};
Target units have neither type-specific methods nor properties.
Device Unit Objects
All device unit objects implement the org.freedesktop.systemd1.Device interface (described here)
in addition to the generic org.freedesktop.systemd1.Unit interface (see above).
$ gdbus introspect --system --dest org.freedesktop.systemd1 \
--object-path /org/freedesktop/systemd1/unit/dev_2ddisk_2dby_5cx2did_2data_5cx2dSAMSUNG_5fHD501LJ_5fS0MUJ1KQ161445_2edevice
node /org/freedesktop/systemd1/unit/dev_2ddisk_2dby_5cx2did_2data_5cx2dSAMSUNG_5fHD501LJ_5fS0MUJ1KQ161445_2edevice {
interface org.freedesktop.systemd1.Unit {
...
};
interface org.freedesktop.systemd1.Device {
methods:
signals:
properties:
readonly s SysFSPath = '/sys/devices/pci0000:00/0000:00:1f.2/ata2/host1/target1:0:0/1:0:0:0/block/sdb';
};
interface org.freedesktop.DBus.Properties {
...
};
interface org.freedesktop.DBus.Peer {
...
};
interface org.freedesktop.DBus.Introspectable {
...
};
};
Properties
Device units only expose a single type-specific property:
SysFSPath contains the sysfs path of the kernel device this object corresponds
to.
Mount Unit Objects
All mount unit objects implement the org.freedesktop.systemd1.Mount
interface (described here) in addition to the generic
org.freedesktop.systemd1.Unit interface (see above)
$ gdbus introspect --system --dest org.freedesktop.systemd1 \
--object-path /org/freedesktop/systemd1/unit/home_2emount
node /org/freedesktop/systemd1/unit/home_2emount {
interface org.freedesktop.systemd1.Unit {
...
};
interface org.freedesktop.systemd1.Mount {
methods:
signals:
properties:
readonly s Where = '/home';
readonly s What = '/dev/mapper/home';
readonly s Options = 'rw,relatime,rw,seclabel,data=ordered';
readonly s Type = 'ext4';
readonly t TimeoutUSec = 90000000;
readonly s Slice = 'system.slice';
readonly s ControlGroup = '/system.slice/home.mount';
readonly a(sasbttuii) ExecMount = [('/bin/mount', ['/bin/mount', '/dev/disk/by-uuid/59a54df8-d070-4907-a4a7-2e0ce05d5c2a', '/home', '-t', 'ext4'], false, 1357656124168977, 11158027, 1357656124274805, 11263855, 608, 1, 0)];
readonly a(sasbttuii) ExecUnmount = [];
readonly a(sasbttuii) ExecRemount = [];
readonly as Environment = [];
readonly a(sb) EnvironmentFiles = [];
readonly u UMask = 18;
readonly t LimitCPU = 18446744073709551615;
readonly t LimitFSIZE = 18446744073709551615;
readonly t LimitDATA = 18446744073709551615;
readonly t LimitSTACK = 18446744073709551615;
readonly t LimitCORE = 18446744073709551615;
readonly t LimitRSS = 18446744073709551615;
readonly t LimitNOFILE = 4096;
readonly t LimitAS = 18446744073709551615;
readonly t LimitNPROC = 61434;
readonly t LimitMEMLOCK = 65536;
readonly t LimitLOCKS = 18446744073709551615;
readonly t LimitSIGPENDING = 61434;
readonly t LimitMSGQUEUE = 819200;
readonly t LimitNICE = 0;
readonly t LimitRTPRIO = 0;
readonly t LimitRTTIME = 18446744073709551615;
readonly s WorkingDirectory = '';
readonly s RootDirectory = '';
readonly i OOMScoreAdjust = 0;
readonly i Nice = 0;
readonly i IOScheduling = 0;
readonly i CPUSchedulingPolicy = 0;
readonly i CPUSchedulingPriority = 0;
readonly ay CPUAffinity = [];
readonly t TimerSlackNSec = 50000;
readonly b CPUSchedulingResetOnFork = false;
readonly b NonBlocking = false;
readonly s StandardInput = 'null';
readonly s StandardOutput = 'journal';
readonly s StandardError = 'inherit';
readonly s TTYPath = '';
readonly b TTYReset = false;
readonly b TTYVHangup = false;
readonly b TTYVTDisallocate = false;
readonly i SyslogPriority = 30;
readonly s SyslogIdentifier = '';
readonly b SyslogLevelPrefix = true;
readonly s Capabilities = '';
readonly i SecureBits = 0;
readonly t CapabilityBoundingSet = 18446744073709551615;
readonly s User = '';
readonly s Group = '';
readonly as SupplementaryGroups = [];
readonly s TCPWrapName = '';
readonly s PAMName = '';
readonly as ReadWriteDirectories = [];
readonly as ReadOnlyDirectories = [];
readonly as InaccessibleDirectories = [];
readonly t MountFlags = 0;
readonly b PrivateTmp = false;
readonly b PrivateNetwork = false;
readonly b SameProcessGroup = true;
readonly s UtmpIdentifier = '';
readonly b IgnoreSIGPIPE = true;
readonly b NoNewPrivileges = false;
readonly au SystemCallFilter = [];
readonly s KillMode = 'control-group';
readonly i KillSignal = 15;
readonly b SendSIGKILL = true;
readonly b SendSIGHUP = false;
readonly b CPUAccounting = false;
readonly t CPUShares = 1024;
readonly b BlockIOAccounting = false;
readonly t BlockIOWeight = 1000;
readonly a(st) BlockIODeviceWeight = [];
readonly a(st) BlockIOReadBandwidth=;
readonly a(st) BlockIOWriteBandwidth=;
readonly b MemoryAccounting = false;
readonly t MemoryLimit = 18446744073709551615;
readonly s DevicePolicy = 'auto';
readonly a(ss) DeviceAllow = [];
readonly u ControlPID = 0;
readonly u DirectoryMode = 493;
readonly s Result = 'success';
};
interface org.freedesktop.DBus.Properties {
...
};
interface org.freedesktop.DBus.Peer {
...
};
interface org.freedesktop.DBus.Introspectable {
...
};
};
Properties
Most of the properties map directly to the corresponding settings in mount unit files. As mount
units invoke the /usr/bin/mount command their bus objects include implicit
ExecMount (and similar) fields which contain information about processes to
execute. They also share most of the fields related to the execution context that Service objects
expose (see above). In addition to these properties there are the following:
ControlPID contains the PID of the currently running
/usr/bin/mount or /usr/bin/umount command if there is one
running, otherwise 0.
Result contains a value explaining why a mount unit failed if it failed. It
can take the values success, resources,
timeout, exit-code, signal,
core-dump which have the identical meaning as the corresponding values of the
corresponding field of service unit objects (see above).
Automount Unit Objects
All automount unit objects implement the
org.freedesktop.systemd1.Automount interface (described here) in addition
to the generic org.freedesktop.systemd1.Unit interface (see above).
$ gdbus introspect --system --dest org.freedesktop.systemd1 \
--object-path /org/freedesktop/systemd1/unit/proc_2dsys_2dfs_2dbinfmt_5fmisc_2eautomount
node /org/freedesktop/systemd1/unit/proc_2dsys_2dfs_2dbinfmt_5fmisc_2eautomount {
interface org.freedesktop.systemd1.Unit {
...
};
interface org.freedesktop.systemd1.Automount {
methods:
signals:
properties:
readonly s Where = '/proc/sys/fs/binfmt_misc';
readonly u DirectoryMode = 493;
readonly s Result = 'success';
};
interface org.freedesktop.DBus.Properties {
...
};
interface org.freedesktop.DBus.Peer {
...
};
interface org.freedesktop.DBus.Introspectable {
...
};
};
Properties
Most of the properties map directly to the corresponding settings in the automount unit
files.
Result knows the values success and
resources, at this time. They have the same meanings as the corresponding values of
the corresponding field of the Service object.
Timer Unit Objects
All timer unit objects implement the org.freedesktop.systemd1.Timer
interface (described here) in addition to the generic
org.freedesktop.systemd1.Unit interface (see above).
$ gdbus introspect --system --dest org.freedesktop.systemd1 \
--object-path /org/freedesktop/systemd1/unit/systemd_2dtmpfiles_2dclean_2etimer
node /org/freedesktop/systemd1/unit/systemd_2dtmpfiles_2dclean_2etimer {
interface org.freedesktop.systemd1.Unit {
...
};
interface org.freedesktop.systemd1.Timer {
readonly s Unit = 'systemd-tmpfiles-clean.service';
readonly a(stt) TimersMonotonic = [('OnUnitActiveUSec', 86400000000, 173700033104), ('OnBootUSec', 900000000, 900000000)];
readonly a(sst) TimersCalendar = [];
readonly t NextElapseUSecRealtime = 0;
readonly t NextElapseUSecMonotonic = 173700033104;
readonly s Result = 'success';
};
interface org.freedesktop.DBus.Properties {
...
};
interface org.freedesktop.DBus.Peer {
...
};
interface org.freedesktop.DBus.Introspectable {
...
};
};
Properties
Unit contains the name of the unit to activate when the timer elapses.
TimersMonotonic contains an array of structs that contain information about
all monotonic timers of this timer unit. The structs contain a string identifying the timer base, which
is one of OnActiveUSec, OnBootUSec,
OnStartupUSec, OnUnitActiveUSec,
OnUnitInactiveUSec, which correspond to the settings of the same names in the timer
unit files; the microsecond offset from this timer base in monotonic time; the next elapsation point on
the CLOCK_MONOTONIC clock, relative its epoch.
TimersCalendar contains an array of structs that contain information about all
realtime/calendar timers of this timer unit. The structs contain a string identifying the timer base,
which may only be OnCalendar for now; the calendar specification string; the next
elapsation point on the CLOCK_REALTIME clock, relative to its epoch.
NextElapseUSecRealtime contains the next elapsation point on the
CLOCK_REALTIME clock in miscroseconds since the epoch, or 0 if this timer event
does not include at least one calendar event.
Similarly, NextElapseUSecMonotonic contains the next elapsation point on the
CLOCK_MONOTONIC clock in microseconds since the epoch, or 0 if this timer event
does not include at least one monotonic event.
Result knows the values success and
resources with the same meanings as the matching values of the corresponding
property of the service interface.
Swap Unit Objects
All swap unit objects implement the org.freedesktop.systemd1.Swap
interface (described here) in addition to the generic
org.freedesktop.systemd1.Unit interface (see above).
$ gdbus introspect --system --dest org.freedesktop.systemd1 \
--object-path /org/freedesktop/systemd1/unit/dev_2dsda3_2eswap
node /org/freedesktop/systemd1/unit/dev_2dsda3_2eswap {
interface org.freedesktop.systemd1.Unit {
...
};
interface org.freedesktop.systemd1.Swap {
methods:
signals:
properties:
readonly s What = '/dev/sda3';
readonly i Priority = -1;
readonly t TimeoutUSec = 90000000;
readonly s Slice = 'system.slice';
readonly s ControlGroup = '';
readonly a(sasbttuii) ExecActivate = [];
readonly a(sasbttuii) ExecDeactivate = [];
readonly as Environment = [];
readonly a(sb) EnvironmentFiles = [];
readonly u UMask = 18;
readonly t LimitCPU = 18446744073709551615;
readonly t LimitFSIZE = 18446744073709551615;
readonly t LimitDATA = 18446744073709551615;
readonly t LimitSTACK = 18446744073709551615;
readonly t LimitCORE = 18446744073709551615;
readonly t LimitRSS = 18446744073709551615;
readonly t LimitNOFILE = 4096;
readonly t LimitAS = 18446744073709551615;
readonly t LimitNPROC = 61434;
readonly t LimitMEMLOCK = 65536;
readonly t LimitLOCKS = 18446744073709551615;
readonly t LimitSIGPENDING = 61434;
readonly t LimitMSGQUEUE = 819200;
readonly t LimitNICE = 0;
readonly t LimitRTPRIO = 0;
readonly t LimitRTTIME = 18446744073709551615;
readonly s WorkingDirectory = '';
readonly s RootDirectory = '';
readonly i OOMScoreAdjust = 0;
readonly i Nice = 0;
readonly i IOScheduling = 0;
readonly i CPUSchedulingPolicy = 0;
readonly i CPUSchedulingPriority = 0;
readonly ay CPUAffinity = [];
readonly t TimerSlackNS = 50000;
readonly b CPUSchedulingResetOnFork = false;
readonly b NonBlocking = false;
readonly s StandardInput = 'null';
readonly s StandardOutput = 'journal';
readonly s StandardError = 'inherit';
readonly s TTYPath = '';
readonly b TTYReset = false;
readonly b TTYVHangup = false;
readonly b TTYVTDisallocate = false;
readonly i SyslogPriority = 30;
readonly s SyslogIdentifier = '';
readonly b SyslogLevelPrefix = true;
readonly s Capabilities = '';
readonly i SecureBits = 0;
readonly t CapabilityBoundingSet = 18446744073709551615;
readonly s User = '';
readonly s Group = '';
readonly as SupplementaryGroups = [];
readonly s TCPWrapName = '';
readonly s PAMName = '';
readonly as ReadWriteDirectories = [];
readonly as ReadOnlyDirectories = [];
readonly as InaccessibleDirectories = [];
readonly t MountFlags = 0;
readonly b PrivateTmp = false;
readonly b PrivateNetwork = false;
readonly b SameProcessGroup = false;
readonly s KillMode = 'control-group';
readonly i KillSignal = 15;
readonly s UtmpIdentifier = '';
readonly b IgnoreSIGPIPE = true;
readonly b NoNewPrivileges = false;
readonly au SystemCallFilter = [];
readonly s KillMode = 'control-group';
readonly i KillSignal = 15;
readonly b SendSIGKILL = true;
readonly b SendSIGHUP = false;
readonly b CPUAccounting = false;
readonly t CPUShares = 1024;
readonly b BlockIOAccounting = false;
readonly t BlockIOWeight = 1000;
readonly a(st) BlockIODeviceWeight = [];
readonly a(st) BlockIOReadBandwidth=;
readonly a(st) BlockIOWriteBandwidth=;
readonly b MemoryAccounting = false;
readonly t MemoryLimit = 18446744073709551615;
readonly s DevicePolicy = 'auto';
readonly a(ss) DeviceAllow = [];
readonly u ControlPID = 0;
readonly s Result = 'success';
};
interface org.freedesktop.DBus.Properties {
...
};
interface org.freedesktop.DBus.Peer {
...
};
interface org.freedesktop.DBus.Introspectable {
...
};
};
Properties
Most of the properties map directly to the corresponding settings in swap unit files. As mount
units invoke the
swapon8 command
their bus objects include implicit ExecActivate (and similar) fields which contain
information about processes to execute. They also share most of the fields related to the execution
context that Service objects expose (see above). In addition to these properties there are the
following:
ControlPID contains the PID of the currently running
swapon8 or
swapoff8 command if
there is one running, otherwise 0.
Result contains a value explaining why a mount unit failed if it failed. It
can take the values success, resources,
timeout, exit-code, signal,
core-dump which have the identical meanings as the corresponding values of the
corresponding field of service unit objects (see above).
Path Unit Objects
$ gdbus introspect --system --dest org.freedesktop.systemd1 \
--object-path /org/freedesktop/systemd1/unit/cups_2epath
node /org/freedesktop/systemd1/unit/cups_2epath {
interface org.freedesktop.systemd1.Unit {
...
};
interface org.freedesktop.systemd1.Path {
methods:
signals:
properties:
readonly s Unit = 'cups.service';
readonly a(ss) Paths = [('PathExistsGlob', '/var/spool/cups/d*')];
readonly b MakeDirectory = false;
readonly u DirectoryMode = 493;
readonly s Result = 'success';
};
interface org.freedesktop.DBus.Properties {
...
};
interface org.freedesktop.DBus.Peer {
...
};
interface org.freedesktop.DBus.Introspectable {
...
};
};
Properties
Most properties correspond directly with the matching settings in path unit files.
The others:
Paths contains an array of structs. Each struct contains the condition to
watch, which can be one of PathExists, PathExistsGlob,
PathChanged, PathModified, DirectoryNotEmpty
which correspond directly to the matching settings in the path unit files; and the path to watch,
possibly including glob expressions.
Result contains a result value which can be success or
resources, which have the same meaning as the corresponding field of the service
interface.
Slice Unit Objects
All slice unit objects implement the org.freedesktop.systemd1.Slice
interface (described here) in addition to the generic
org.freedesktop.systemd1.Unit interface (see above).
$ gdbus introspect --system --dest org.freedesktop.systemd1 \
--object-path /org/freedesktop/systemd1/unit/system_2eslice
node /org/freedesktop/systemd1/unit/system_2eslice {
interface org.freedesktop.systemd1.Unit {
...
};
interface org.freedesktop.systemd1.Slice {
methods:
signals:
properties:
readonly s Slice = '-.slice';
readonly s ControlGroup = '/system.slice';
readonly b CPUAccounting = false;
readonly t CPUShares = 1024;
readonly b BlockIOAccounting = false;
readonly t BlockIOWeight = 1000;
readonly a(st) BlockIODeviceWeight = [];
readonly a(st) BlockIOReadBandwidth=;
readonly a(st) BlockIOWriteBandwidth=;
readonly b MemoryAccounting = false;
readonly t MemoryLimit = 18446744073709551615;
readonly s DevicePolicy = 'auto';
readonly a(ss) DeviceAllow = [];
};
interface org.freedesktop.DBus.Properties {
...
};
interface org.freedesktop.DBus.Peer {
...
};
interface org.freedesktop.DBus.Introspectable {
...
};
};
Properties
Most properties correspond directly with the matching settings in slice unit files.
Scope Unit Objects
All slice unit objects implement the org.freedesktop.systemd1.Scope
interface (described here) in addition to the generic
org.freedesktop.systemd1.Unit interface (see above).
$ gdbus introspect --system --dest org.freedesktop.systemd1 \
--object-path /org/freedesktop/systemd1/unit/session_2d1_2escope
node /org/freedesktop/systemd1/unit/session_2d1_2escope {
interface org.freedesktop.systemd1.Unit {
...
};
interface org.freedesktop.systemd1.Scope {
methods:
Abandon();
signals:
RequestStop();
properties:
readonly s Slice = 'user-1000.slice';
readonly s ControlGroup = '/user.slice/user-1000.slice/session-1.scope';
readonly t TimeoutStopUSec = 500000;
readonly s KillMode = 'none';
readonly i KillSignal = 15;
readonly b SendSIGKILL = true;
readonly b SendSIGHUP = true;
readonly b CPUAccounting = false;
readonly t CPUShares = 1024;
readonly b BlockIOAccounting = false;
readonly t BlockIOWeight = 1000;
readonly a(st) BlockIODeviceWeight = [];
readonly a(st) BlockIOReadBandwidth=;
readonly a(st) BlockIOWriteBandwidth=;
readonly b MemoryAccounting = false;
readonly t MemoryLimit = 18446744073709551615;
readonly s DevicePolicy = 'auto';
readonly a(ss) DeviceAllow = [];
readonly s Result = 'success';
readonly s Controller = '';
};
interface org.freedesktop.DBus.Properties {
...
};
interface org.freedesktop.DBus.Peer {
...
};
interface org.freedesktop.DBus.Introspectable {
...
};
};
Methods
Abandon() may be used to place a scope unit in the "abandoned" state. This
may be used to inform the system manager that the manager that created the scope lost interest in the
scope (for example, because it is terminating), without wanting to shut down the scope entirely
Signals
RequestStop is sent to the peer that is configured in the
Controller property when systemd is requested to terminate the scope unit. A program
registering a scope can use this to cleanly shut down the processes it added to the scope, instead of
letting systemd do it with the usual SIGTERM logic.
Properties
All properties correspond directly with the matching properties of service units
Controller contains the bus name (unique or well-known) that is notified when
the scope unit is to be shut down via a RequestStop signal (see below). This is
set when the scope is created. If not set the scope's processes will terminated with
SIGTERM directly.
Job Objects
Job objects encapsulate scheduled or running jobs. Each unit can have none or one jobs in the
execution queue. Each job is attached to exactly one unit.
$ gdbus introspect --system --dest org.freedesktop.systemd1 \
--object-path /org/freedesktop/systemd1/job/1292
node /org/freedesktop/systemd1/job/1292 {
interface org.freedesktop.systemd1.Job {
methods:
Cancel();
signals:
properties:
readonly u Id = 1292;
readonly (so) Unit = ('slow.service', '/org/freedesktop/systemd1/unit/slow_2eservice');
readonly s JobType = 'start';
readonly s State = 'running';
};
interface org.freedesktop.DBus.Properties {
...
};
interface org.freedesktop.DBus.Peer {
...
};
interface org.freedesktop.DBus.Introspectable {
...
};
};
Methods
Cancel() cancels the job. Note that this will remove a job from the queue if
it is not yet executed but generally will not cause a job that is already in the process of being
executed to be aborted. This operation may also be requested via the CancelJob()
method of the Manager object (see above), which is sometimes useful to reduce roundtrips.
Properties
Id is the numeric Id of the job. During the runtime of a systemd instance each
numeric ID is only assigned once.
Unit refers to the unit this job belongs two. It is a structure consisting of
the name of the unit and a bus path to the unit's object.
JobType refers to the job's type and is one of start,
verify-active, stop, reload,
restart, try-restart, reload-or-start. Note
that later versions might define additional values.
State refers to the job's state and is one of waiting and
running. The former indicates that a job is currently queued but has not begun to
execute yet, the latter indicates that a job is currently being executed.
Versioning
These D-Bus interfaces follow
the usual interface versioning guidelines.