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SYSTEMD.SERVICE(5)		systemd.service		    SYSTEMD.SERVICE(5)

NAME
       systemd.service - systemd service configuration files

SYNOPSIS
       systemd.service

DESCRIPTION
       A 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.unit(5) 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.exec(5), which define the
       execution environment the commands are executed in.

       Unless DefaultDependencies= is set to false, service units will
       implicitly have dependencies of type Requires= and After= on
       basic.target as well as dependencies of type Conflicts= and Before= on
       shutdown.target. These ensure that normal service units pull in basic
       system initialization, and are terminated cleanly prior to system
       shutdown. Only services involved with early boot or late system
       shutdown should disable this option.

       If a service is requested under a certain name but no unit
       configuration file is found, systemd looks for a SysV init script by
       the same name (with the .service suffix removed) and dynamically
       creates a service unit from that script. This is useful for
       compatibility with SysV.

OPTIONS
       Service 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.exec(5). 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
	   simple, forking, oneshot, dbus, notify.

	   If set to simple (the default value) it is expected that the
	   process configured with ExecStart= is the main process of the
	   service. In this mode, if the process offers functionality to other
	   processes on the system its communication channels should 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 forking it is expected that the process configured with
	   ExecStart= will call fork() as part of its start-up. The parent
	   process is expected to exit 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 oneshot is similar to simple, however it is expected
	   that the process has to exit before systemd starts follow-up units.
	   RemainAfterExit= is particularly useful for this type of service.

	   Behaviour of dbus is similar to simple, 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. Service units with this option
	   configured implicitly gain dependencies on the dbus.target unit.

	   Behaviour of notify is similar to simple, however it is expected
	   that the daemon sends a notification message via sd_notify(3) 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 NotifyAccess= (see below) should be
	   set to open access to the notification socket provided by systemd.
	   If NotifyAccess= is not set, it will implicitly be set to main.

       RemainAfterExit=
	   Takes a boolean value that specifies whether the service shall be
	   considered active even when all its processes exited. Defaults to
	   no.

       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 forking.

       BusName=
	   Takes a D-Bus bus name, where this service is reachable as. This
	   option is mandatory for services where Type= is set to dbus, 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, except when Type=oneshot is used in
	   which case more than one ExecStart= line is accepted which are then
	   invoked one by one, sequentially in the order they appear in the
	   unit file.

	   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. If the first token is
	   prefixed with - an exit code of the command normally considered a
	   failure (i.e. non-zero exit status or abnormal exit due to signal)
	   is ignored and considered success. If both - and @ are used for the
	   same command the former must precede the latter. Unless
	   Type=forking is set, the process started via this command line will
	   be considered the main process of the daemon. The command line
	   accepts % specifiers as described in systemd.unit(5). On top of
	   that basic environment variable substitution is supported, where
	   ${FOO} is replaced by the string value of the environment variable
	   of the same name. Also $FOO may appear as separate word on the
	   command line in which case the variable is replaced by its value
	   split at whitespaces. Note that the first argument (i.e. the binary
	   to execute) may not be a variable, and must be a literal and
	   absolute path name.

       ExecStartPre=, ExecStartPost=
	   Additional commands that are executed before (resp. after) the
	   command in ExecStart=. Multiple command lines may be concatenated
	   in a single directive, by separating them by semicolons (these
	   semicolons must be passed as separate words). In that case, the
	   commands are executed one after the other, serially. Alternatively,
	   these directives may be specified more than once with the same
	   effect. However, the latter syntax is not recommended for
	   compatibility with parsers suitable for XDG .desktop files. Use of
	   these settings is optional. Specifier and environment variable
	   substitution is supported.

       ExecReload=
	   Commands to execute to trigger a configuration reload in the
	   service. This argument takes multiple command lines, following the
	   same scheme as pointed out for ExecStartPre= above. Use of this
	   setting is optional. Specifier and environment variable
	   substitution is supported here following the same scheme as for
	   ExecStart=. One special environment variable is set: if known
	   $MAINPID is set to the main process of the daemon, and may be used
	   for command lines like the following: /bin/kill -HUP $MAINPID.

       ExecStop=
	   Commands to execute to stop the service started via ExecStart=.
	   This argument takes multiple command lines, following the same
	   scheme as pointed out for ExecStartPre= above. 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. Specifier and environment variable substitution is
	   supported (including $MAINPID, see above).

       ExecStopPost=
	   Additional commands that are executed after the service was stopped
	   using the commands configured in ExecStop=. This argument takes
	   multiple command lines, following the same scheme as pointed out
	   for ExecStartPre. Use of these settings is optional. Specifier and
	   environment variable substitution is supported.

       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 KillMode=
	   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 exits. Takes one of no, on-success, on-failure, on-abort or
	   always. If set to no (the default) the service will not be
	   restarted when it exits. If set to on-success it will be restarted
	   only when it exited cleanly, i.e. terminated with an exit code of
	   0. If set to on-failure it will be restarted only when it exited
	   with an exit code not equalling 0, or when terminated by a signal.
	   If set to on-abort it will be restarted only if it exits due to
	   reception of an uncaught signal. If set to always 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.exec(5) 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.exec(5) 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.unit(5). If used, pass an integer
	   value in the range 0-99.

       KillMode=
	   Specifies how processes of this service shall be killed. One of
	   control-group, process-group, process, none.

	   If set to control-group 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
	   process-group only the members of the process group of the main
	   service process are killed. If set to process only the main process
	   itself is killed. If set to none 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 control-group.

	   Processes will first be terminated via SIGTERM (unless the signal
	   to send is changed via KillSignal=). If then after a delay
	   (configured via the TimeoutSec= option) processes still remain, the
	   termination request is repeated with the SIGKILL signal (unless
	   this is disabled via the SendSIGKILL= option). See kill(2) for more
	   information.

       KillSignal=
	   Specifies which signal to use when killing a service. Defaults to
	   SIGTERM.

       SendSIGKILL=
	   Specifies whether to send SIGKILL to remaining processes after a
	   timeout, if the normal shutdown procedure left processes of the
	   service around. Takes a boolean value. Defaults to "yes".

       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.socket(5).
	   Defaults to false.

       NotifyAccess=
	   Controls access to the service status notification socket, as
	   accessible via the sd_notify(3) call. Takes one of none (the
	   default), main or all. If none no daemon status updates are
	   accepted from the service processes, all status update messages are
	   ignored. If main only service updates sent from the main process of
	   the service are accepted. If all 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).

       Sockets=
	   Specifies the name of the socket units this service shall inherit
	   the sockets from when the service (ignoring the different suffix of
	   course) is started. Normally it should not be necessary to use this
	   setting as all sockets whose unit shares the same name as the
	   service are passed to the spawned process.

	   Note that the same socket may be passed to multiple processes at
	   the same time. Also note that a different service may be activated
	   on incoming traffic than inherits the sockets. Or in other words:
	   The Service= setting of .socket units doesn't have to match the
	   inverse of the Sockets= setting of the .service it refers to.

       FsckPassNo=
	   Set the fsck passno priority to use to order this service in
	   relation to other file system checking services. This option is
	   only necessary to fix ordering in relation to fsck jobs
	   automatically created for all /etc/fstab entries with a value in
	   the fs_passno column > 0. As such it should only be used as option
	   for fsck services. Almost always it is a better choice to add
	   explicit ordering directives via After= or Before=, instead. For
	   more details see systemd.unit(5). If used, pass an integer value in
	   the same range as /etc/fstab's fs_passno column. See fstab(5) for
	   details.

SEE ALSO
       systemd(1), systemctl(8), systemd.unit(5), systemd.exec(5)

AUTHOR
       Lennart Poettering <lennart@poettering.net>
	   Developer

systemd				  01/22/2011		    SYSTEMD.SERVICE(5)


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