X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=man%2Fsystemd.service.xml;h=e4fa6bcc7c6fc14177c774754c74854352c0082a;hp=5230a78337e34b9ca3a2e532b83283928c4b748d;hb=5471472d441d9ac48640f11a3b07e6a1fd6d1b63;hpb=af62c704053b5d34672497eb5bdc4764ebbb5f4f diff --git a/man/systemd.service.xml b/man/systemd.service.xml index 5230a7833..e4fa6bcc7 100644 --- a/man/systemd.service.xml +++ b/man/systemd.service.xml @@ -54,148 +54,615 @@ Description - A configuration file ending in .service encodes - information about a process controlled and supervised - by systemd. + 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.unit5 for the common options of all unit configuration - files. + 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. + + Unless DefaultDependencies= + is set to , 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.exec5. The + options specific to the [Service] + section of service units are the following: + Type= - - One of - forking, - simple, - finish, - dbus. - - If set to - forking - (the default) 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. - - If set to - simple (the - recommended value) it is - expected that the process - configured with - ExecStart= - is the main process of the - daemon. In this mode, - communication channels must be - available before the daemon is - started up (sockets set up by systemd), - as systemd will immediately proceed - starting follow-up units. - - Behaviour of - finish is - similar to - simple, - 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 - 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. + + 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, 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 + 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 + is similar + to , 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 + 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. Service units with this + option configured implicitly gain + dependencies on the + dbus.target + unit. + + 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 + 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 + . + - ValidNoProcess= - - Takes a boolean value - that specifies whether the service - shall be considered active - even when all its processes - exited. Defaults to no. + RemainAfterExit= + + 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 - forking. + + 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 - dbus, but - its use is otherwise - recommended as well if the - process takes a name on the - D-Bus bus. + + 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 word of the - command line must be an - absolute file name. It is - mandatory to set this option - for all services. - + 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.unit5. 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 + , + , + , + 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 + it will be + restarted only when it exited with an + exit code not equalling 0, or when + terminated by a signal. If set to + it will be + restarted only if it exits due to + reception of an uncaught signal. 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 + TimeoutSec= 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 from 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). + + + + 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.unit5. If + used, pass an integer value in the + same range as + /etc/fstab's + fs_passno column. See + fstab5 + for details. @@ -204,9 +671,10 @@ See Also - systemd8, - systemctl8 - systemd.unit5 + systemd1, + systemctl8, + systemd.unit5, + systemd.exec5