systemd.servicesystemdDeveloperLennartPoetteringlennart@poettering.netsystemd.service5systemd.servicesystemd service configuration filessystemd.serviceDescriptionA unit configuration file whose name ends in
.service encodes information
about a process controlled and supervised by
systemd.This man page lists the configuration options
specific to this unit type. See
systemd.unit5
for the common options of all unit configuration
files. The common configuration items are configured
in the generic [Unit] and [Install] sections. The
service specific configuration options are configured
in the [Service] section.Additional options are listed in
systemd.exec5,
which define the execution environment the commands
are executed in.OptionsService files must include a [Service] section,
which carries information about the service and the
process it supervises. A number of options that may be
used in this section are shared with other unit
types. These options are documented in
systemd.exec5. The
options specific to the [Service] section of service
units are the following:Type=Configures the process
start-up type for this service
unit. One of ,
,
,
,
.If set to
(the default
value) it is expected that the process
configured with
ExecStart= is the
main process of the service. In this
mode, communication channels must be
installed before the daemon is started
up (e.g. sockets set up by systemd,
via socket activation), as systemd
will immediately proceed starting
follow-up units.If set to
it is
expected that the process configured
with ExecStart=
will start up and call
fork(). The
parent process is expected to finish
when start-up is complete and all
communication channels set up. The
child continues to run as the main
daemon process. This is the behaviour
of traditional UNIX daemons. If this
setting is used, it is recommended to
also use the
PIDFile= option, so
that systemd can identify the main
process of the daemon. systemd will
proceed starting follow-up units as
soon as the parent process
exits.Behaviour of
is similar
to , however
it is expected that the process has to
exit before systemd starts follow-up
units. ValidNoProcess=
is particularly useful for this type
of service.Behaviour of
is similar to
, however it
is expected that the daemon acquires a
name on the D-Bus bus, as configured
by
BusName=. systemd
will proceed starting follow-up units
after the D-Bus bus name has been
acquired.Behaviour of
is similar to
, however it is
expected that the daemon sends a
notification message via
sd_notify3
or an equivalent call when it finished
starting up. systemd will proceed
starting follow-up units after this
notification message has been sent. If
this option is used
(see
below) must be set to open access to
the notification socket provided by
systemd.ValidNoProcess=Takes a boolean value
that specifies whether the service
shall be considered active even when
all its processes exited. Defaults to
.PIDFile=Takes an absolute file
name pointing to the PID file of this
daemon. Use of this option is
recommended for services where
Type= is set to
.BusName=Takes a D-Bus bus
name, where this service is reachable
as. This option is mandatory for
services where
Type= is set to
, but its use
is otherwise recommended as well if
the process takes a name on the D-Bus
bus.ExecStart=Takes a command line
that is executed when this service
shall be started up. The first token
of the command line must be an
absolute file name, then followed by
arguments for the process. It is
mandatory to set this option for all
services. This option may not be
specified more than once. Optionally,
if the absolute file name is prefixed
with @, the second token will be
passed as argv[0] to the executed
process, followed by the further
arguments specified. Unless
is set,
the process started via this command
line will be considered the main
process of the
daemon.ExecStartPre=ExecStartPost=Additional commands
that are executed before (resp. after)
the command in
ExecStart=. If
specified more than once, all commands
are executed one after the other,
serially. Use of these settings is
optional.ExecReload=Commands to execute to
trigger a configuration reload in the
service. If used more than once, all
commands are executed one after the
other, serially. Use of this setting is optional.
ExecStop=Commands to execute to
stop the service started via
ExecStart=. If used
more than once, all commands are
executed one after the other,
serially. Use of this setting is
optional. All processes remaining for
a service after the commands
configured in this option are run are
terminated according to the
KillMode= setting
(see below). If this option is not
specified the process is terminated
right-away when service stop is
requested.ExecStopPost=Additional commands
that are executed after the service
was stopped using the commands
configured in
ExecStop=. If
specified more than once, all commands
are executed one after the other,
serially. Use of these settings is
optional.RestartSec=Configures the time to
sleep before restarting a service (as
configured with
Restart=). Takes a
unit-less value in seconds, or a time
span value such as "5min
20s". Defaults to
100ms.TimeoutSec=Configures the time to
wait for start-up and stop. If a
daemon service does not signal
start-up completion within the
configured time the service will be
considered failed and be shut down
again. If a service is asked to stop
but does not terminate in the
specified time it will be terminated
forcibly via SIGTERM, and after
another delay of this time with
SIGKILL. (See
below.) Takes a unit-less value in seconds, or a
time span value such as "5min
20s". Pass 0 to disable the timeout
logic. Defaults to
60s.Restart=Configures whether the
main service process shall be restarted when
it exists. Takes one of
,
or
. If
set to (the
default) the service will not be
restarted when it exits. If set to
it
will be restarted only when it exited
cleanly, i.e. terminated with an exit
code of 0. If set to
the
service will be restarted regardless
whether it exited cleanly or not, or
got terminated abnormally by a
signal.PermissionsStartOnly=Takes a boolean
argument. If true, the permission
related execution options as
configured with
User= and similar
options (see
systemd.exec5
for more information) are only applied
to the process started with
ExecStart=, and not
to the various other
ExecStartPre=,
ExecStartPost=,
ExecReload=,
ExecStop=,
ExecStopPost=
commands. If false, the setting is
applied to all configured commands the
same way. Defaults to
false.RootDirectoryStartOnly=Takes a boolean
argument. If true, the root directory
as configured with the
RootDirectory=
option (see
systemd.exec5
for more information) is only applied
to the process started with
ExecStart=, and not
to the various other
ExecStartPre=,
ExecStartPost=,
ExecReload=,
ExecStop=,
ExecStopPost=
commands. If false, the setting is
applied to all configured commands the
same way. Defaults to
false.SysVStartPriority=Set the SysV start
priority to use to order this service
in relation to SysV services lacking
LSB headers. This option is only
necessary to fix ordering in relation
to legacy SysV services, that have no
ordering information encoded in the
script headers. As such it should only
be used as temporary compatibility
option, and not be used in new unit
files. Almost always it is a better
choice to add explicit ordering
directives via
After= or
Before=,
instead. For more details see
systemd.unit5. If
used, pass an integer value in the
range 0-99.KillMode=Specifies how
processes of this service shall be
killed. One of
,
,
,
.If set to
all
remaining processes in the control
group of this service will be
terminated on service stop, after the
stop command (as configured with
ExecStop=) is
executed. If set to
only
the members of the process group of
the main service process are
killed. If set to
only the main
process itself is killed. If set to
no process is
killed. In this case only the stop
command will be executed on service
stop, but no process be killed
otherwise. Processes remaining alive
after stop are left in their control
group and the control group continues
to exist after stop unless it is
empty. Defaults to
.Processes will first be
terminated via SIGTERM. If then after
a delay (configured via the
option)
processes still remain, the
termination request is repeated with
the SIGKILL signal. See
kill2
for more
information.NonBlocking=Set O_NONBLOCK flag
for all file descriptors passed via
socket-based activation. If true, all
file descriptors >= 3 (i.e. all except
STDIN/STDOUT/STDERR) will have
the O_NONBLOCK flag set and hence are in
non-blocking mode. This option is only
useful in conjunction with a socket
unit, as described in
systemd.socket5. Defaults
to false.NotifyAccess=Controls access to the
service status notification socket, as
accessible via the
sd_notify3
call. Takes one of
(the default),
or
. If
no daemon status
updates are accepted by the service
processes, all status update messages
are ignored. If
only service updates sent from the
main process of the service are
accepted. If all
services updates from all members of
the service's control group are
accepted. This option must be set to
open access to the notification socket
when using
Type=notify (see above).See Alsosystemd8,
systemctl8,
systemd.unit5,
systemd.exec5