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7 This file is part of systemd.
9 Copyright 2010 Lennart Poettering
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25 <refentry id="systemd.service">
27 <title>systemd.service</title>
28 <productname>systemd</productname>
32 <contrib>Developer</contrib>
33 <firstname>Lennart</firstname>
34 <surname>Poettering</surname>
35 <email>lennart@poettering.net</email>
41 <refentrytitle>systemd.service</refentrytitle>
42 <manvolnum>5</manvolnum>
46 <refname>systemd.service</refname>
47 <refpurpose>Service unit configuration</refpurpose>
51 <para><filename><replaceable>service</replaceable>.service</filename></para>
55 <title>Description</title>
57 <para>A unit configuration file whose name ends in
58 <filename>.service</filename> encodes information
59 about a process controlled and supervised by
62 <para>This man page lists the configuration options
63 specific to this unit type. See
64 <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>
65 for the common options of all unit configuration
66 files. The common configuration items are configured
67 in the generic <literal>[Unit]</literal> and
68 <literal>[Install]</literal> sections. The service
69 specific configuration options are configured in the
70 <literal>[Service]</literal> section.</para>
72 <para>Additional options are listed in
73 <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
74 which define the execution environment the commands
75 are executed in, and in
76 <citerefentry><refentrytitle>systemd.kill</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
77 which define the way the processes of the service are
79 <citerefentry><refentrytitle>systemd.resource-control</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
80 which configure resource control settings for the
81 processes of the service.</para>
83 <para>Unless <varname>DefaultDependencies=</varname>
84 is set to <option>false</option>, service units will
85 implicitly have dependencies of type
86 <varname>Requires=</varname> and
87 <varname>After=</varname> on
88 <filename>basic.target</filename> as well as
89 dependencies of type <varname>Conflicts=</varname> and
90 <varname>Before=</varname> on
91 <filename>shutdown.target</filename>. These ensure
92 that normal service units pull in basic system
93 initialization, and are terminated cleanly prior to
94 system shutdown. Only services involved with early
95 boot or late system shutdown should disable this
98 <para>If a service is requested under a certain name
99 but no unit configuration file is found, systemd looks
100 for a SysV init script by the same name (with the
101 <filename>.service</filename> suffix removed) and
102 dynamically creates a service unit from that
103 script. This is useful for compatibility with
104 SysV. Note that this compatibility is quite
105 comprehensive but not 100%. For details about the
106 incompatibilities, see the <ulink
107 url="http://www.freedesktop.org/wiki/Software/systemd/Incompatibilities">Incompatibilities
108 with SysV</ulink> document.
113 <title>Options</title>
115 <para>Service files must include a
116 <literal>[Service]</literal> section, which carries
117 information about the service and the process it
118 supervises. A number of options that may be used in
119 this section are shared with other unit types. These
120 options are documented in
121 <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>
123 <citerefentry><refentrytitle>systemd.kill</refentrytitle><manvolnum>5</manvolnum></citerefentry>. The
124 options specific to the <literal>[Service]</literal>
125 section of service units are the following:</para>
127 <variablelist class='unit-directives'>
129 <term><varname>Type=</varname></term>
131 <listitem><para>Configures the process
132 start-up type for this service
133 unit. One of <option>simple</option>,
134 <option>forking</option>,
135 <option>oneshot</option>,
136 <option>dbus</option>,
137 <option>notify</option> or
138 <option>idle</option>.</para>
141 <option>simple</option> (the default
143 <varname>Type=</varname> nor
144 <varname>BusName=</varname> are
145 specified), it is expected that the
146 process configured with
147 <varname>ExecStart=</varname> is the
148 main process of the service. In this
149 mode, if the process offers
150 functionality to other processes on
151 the system, its communication channels
152 should be installed before the daemon
153 is started up (e.g. sockets set up by
154 systemd, via socket activation), as
155 systemd will immediately proceed
156 starting follow-up units.</para>
159 <option>forking</option>, it is
160 expected that the process configured
161 with <varname>ExecStart=</varname>
162 will call <function>fork()</function>
163 as part of its start-up. The parent process is
164 expected to exit when start-up is
165 complete and all communication
166 channels are set up. The child continues
167 to run as the main daemon
168 process. This is the behavior of
169 traditional UNIX daemons. If this
170 setting is used, it is recommended to
172 <varname>PIDFile=</varname> option, so
173 that systemd can identify the main
174 process of the daemon. systemd will
175 proceed with starting follow-up units
176 as soon as the parent process
180 <option>oneshot</option> is similar
181 to <option>simple</option>; however,
182 it is expected that the process has to
183 exit before systemd starts follow-up
184 units. <varname>RemainAfterExit=</varname>
185 is particularly useful for this type
189 <option>dbus</option> is similar to
190 <option>simple</option>; however, it is
191 expected that the daemon acquires a
192 name on the D-Bus bus, as configured
194 <varname>BusName=</varname>. systemd
195 will proceed with starting follow-up
196 units after the D-Bus bus name has been
197 acquired. Service units with this
198 option configured implicitly gain
200 <filename>dbus.socket</filename>
201 unit. This type is the default if
202 <varname>BusName=</varname> is
206 <option>notify</option> is similar to
207 <option>simple</option>; however, it is
208 expected that the daemon sends a
209 notification message via
210 <citerefentry><refentrytitle>sd_notify</refentrytitle><manvolnum>3</manvolnum></citerefentry>
211 or an equivalent call when it has finished
212 starting up. systemd will proceed with
213 starting follow-up units after this
214 notification message has been sent. If
216 <varname>NotifyAccess=</varname> (see
217 below) should be set to open access to
218 the notification socket provided by
220 <varname>NotifyAccess=</varname> is
221 not set, it will be implicitly set to
222 <option>main</option>. Note that
224 <varname>Type=</varname><option>notify</option>
225 will not work if used in combination with
226 <varname>PrivateNetwork=</varname><option>yes</option>.</para>
229 <option>idle</option> is very similar
230 to <option>simple</option>; however,
231 actual execution of the service
232 binary is delayed until all jobs are
233 dispatched. This may be used to avoid
234 interleaving of output of shell
235 services with the status output on the
241 <term><varname>RemainAfterExit=</varname></term>
243 <listitem><para>Takes a boolean value
244 that specifies whether the service
245 shall be considered active even when
246 all its processes exited. Defaults to
247 <option>no</option>.</para>
252 <term><varname>GuessMainPID=</varname></term>
254 <listitem><para>Takes a boolean value
255 that specifies whether systemd should
256 try to guess the main PID of a service
257 if it cannot be determined
258 reliably. This option is ignored
259 unless <option>Type=forking</option>
260 is set and <option>PIDFile=</option>
261 is unset because for the other types
262 or with an explicitly configured PID
263 file, the main PID is always known. The
264 guessing algorithm might come to
265 incorrect conclusions if a daemon
266 consists of more than one process. If
267 the main PID cannot be determined,
268 failure detection and automatic
269 restarting of a service will not work
270 reliably. Defaults to
271 <option>yes</option>.</para>
276 <term><varname>PIDFile=</varname></term>
278 <listitem><para>Takes an absolute file
279 name pointing to the PID file of this
280 daemon. Use of this option is
281 recommended for services where
282 <varname>Type=</varname> is set to
283 <option>forking</option>. systemd will
284 read the PID of the main process of
285 the daemon after start-up of the
286 service. systemd will not write to the
287 file configured here.</para>
292 <term><varname>BusName=</varname></term>
294 <listitem><para>Takes a D-Bus bus
295 name that this service is reachable
296 as. This option is mandatory for
298 <varname>Type=</varname> is set to
299 <option>dbus</option>, but its use
300 is otherwise recommended if the process
301 takes a name on the D-Bus bus.</para>
306 <term><varname>ExecStart=</varname></term>
307 <listitem><para>Commands with their
308 arguments that are executed when this
309 service is started. For each of the
310 specified commands, the first argument
311 must be an absolute and literal path
312 to an executable.</para>
314 <para>When <varname>Type</varname> is
315 not <option>oneshot</option>, only one
316 command may be given. When
317 <varname>Type=oneshot</varname> is
318 used, more than one command may be
319 specified. Multiple command lines may
320 be concatenated in a single directive
321 by separating them with semicolons
322 (these semicolons must be passed as
323 separate words). Alternatively, this
324 directive may be specified more than
325 once with the same effect.
326 Lone semicolons may be escaped as
327 <literal>\;</literal>. If the empty
328 string is assigned to this option, the
329 list of commands to start is reset,
330 prior assignments of this option will
331 have no effect.</para>
333 <para>Each command line is split on
334 whitespace, with the first item being
335 the command to execute, and the
336 subsequent items being the arguments.
337 Double quotes ("...") and single
338 quotes ('...') may be used, in which
339 case everything until the next
340 matching quote becomes part of the
341 same argument. Quotes themselves are
342 removed after parsing. In addition, a
344 (<literal>\</literal>) may be used to
345 merge lines. This syntax is intended
346 to be very similar to shell syntax,
347 but only the meta-characters and
348 expansions described in the following
349 paragraphs are understood.
350 Specifically, redirection using
351 <literal><</literal>,
352 <literal><<</literal>,
353 <literal>></literal>, and
354 <literal>>></literal>, pipes
355 using <literal>|</literal>, and
356 running programs in the background
357 using <literal>&</literal>
358 and <emphasis>other elements of shell
359 syntax are not supported</emphasis>.
362 <para>If more than one command is
363 specified, the commands are invoked
364 sequentially in the order they appear
365 in the unit file. If one of the
366 commands fails (and is not prefixed
367 with <literal>-</literal>), other lines
368 are not executed, and the unit is
369 considered failed.</para>
372 <varname>Type=forking</varname> is
373 set, the process started via this
374 command line will be considered the
375 main process of the daemon.</para>
377 <para>The command line accepts
378 <literal>%</literal> specifiers as
380 <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>.
381 Note that the first argument of the
382 command line (i.e. the program to
383 execute) may not include
386 <para>Basic environment variable
387 substitution is supported. Use
388 <literal>${FOO}</literal> as part of a
389 word, or as a word of its own, on the
390 command line, in which case it will be
391 replaced by the value of the
392 environment variable including all
393 whitespace it contains, resulting in a
395 <literal>$FOO</literal> as a separate
396 word on the command line, in which
397 case it will be replaced by the value
398 of the environment variable split at
399 whitespace, resulting in zero or more
400 arguments. To pass a literal dollar
401 sign, use <literal>$$</literal>.
402 Variables whose value is not known at
403 expansion time are treated as empty
404 strings. Note that the first argument
405 (i.e. the program to execute) may not
406 be a variable.</para>
408 <para>Variables to be used in this
409 fashion may be defined through
410 <varname>Environment=</varname> and
411 <varname>EnvironmentFile=</varname>.
412 In addition, variables listed in the
413 section "Environment variables in
414 spawned processes" in
415 <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
416 which are considered "static
417 configuration", may be used (this includes
418 e.g. <varname>$USER</varname>, but not
419 <varname>$TERM</varname>).</para>
421 <para>Optionally, if the absolute file
422 name is prefixed with
423 <literal>@</literal>, the second token
425 <literal>argv[0]</literal> to the
426 executed process, followed by the
427 further arguments specified. If the
428 absolute filename is prefixed with
429 <literal>-</literal>, an exit code of
430 the command normally considered a
431 failure (i.e. non-zero exit status or
432 abnormal exit due to signal) is ignored
433 and considered success. If both
434 <literal>-</literal> and
435 <literal>@</literal> are used, they
436 can appear in either order.</para>
438 <para>Note that this setting does not
439 directly support shell command
440 lines. If shell command lines are to
441 be used, they need to be passed
442 explicitly to a shell implementation
443 of some kind. Example:</para>
444 <programlisting>ExecStart=/bin/sh -c 'dmesg | tac'</programlisting>
445 <para>Example:</para>
446 <programlisting>ExecStart=/bin/echo one ; /bin/echo "two two"</programlisting>
447 <para>This will execute
448 <command>/bin/echo</command> two
449 times, each time with one argument:
450 <literal>one</literal> and
451 <literal>two two</literal>,
452 respectively. Because two commands are
454 <varname>Type=oneshot</varname> must
457 <para>Example:</para>
458 <programlisting>ExecStart=/bin/echo / >/dev/null & \; \
459 /bin/ls</programlisting>
460 <para>This will execute
461 <command>/bin/echo</command> with five
462 arguments: <literal>/</literal>,
463 <literal>>/dev/null</literal>,
464 <literal>&</literal>,
465 <literal>;</literal>, and
466 <literal>/bin/ls</literal>.</para>
468 <para>Example:</para>
469 <programlisting>Environment="ONE=one" 'TWO=two two'
470 ExecStart=/bin/echo $ONE $TWO ${TWO}</programlisting>
471 <para>This will execute
472 <command>/bin/echo</command> with four
473 arguments: <literal>one</literal>,
474 <literal>two</literal>,
475 <literal>two</literal>, and
476 <literal>two two</literal>.</para>
481 <term><varname>ExecStartPre=</varname></term>
482 <term><varname>ExecStartPost=</varname></term>
483 <listitem><para>Additional commands
484 that are executed before or after
486 <varname>ExecStart=</varname>, respectively.
487 Syntax is the same as for
488 <varname>ExecStart=</varname>, except
489 that multiple command lines are allowed
490 and the commands are executed one
491 after the other, serially.</para>
493 <para>If any of those commands (not
494 prefixed with <literal>-</literal>)
495 fail, the rest are not executed and
496 the unit is considered failed.</para>
501 <term><varname>ExecReload=</varname></term>
502 <listitem><para>Commands to execute to
503 trigger a configuration reload in the
504 service. This argument takes multiple
505 command lines, following the same
506 scheme as described for
507 <varname>ExecStart=</varname>
508 above. Use of this setting is
509 optional. Specifier and environment
510 variable substitution is supported
511 here following the same scheme as for
512 <varname>ExecStart=</varname>.</para>
514 <para>One additional, special
515 environment variable is set: if known,
516 <varname>$MAINPID</varname> is set to
517 the main process of the daemon, and
518 may be used for command lines like the
521 <programlisting>/bin/kill -HUP $MAINPID</programlisting>
526 <term><varname>ExecStop=</varname></term>
527 <listitem><para>Commands to execute to
528 stop the service started via
529 <varname>ExecStart=</varname>. This
530 argument takes multiple command lines,
531 following the same scheme as described
532 for <varname>ExecStart=</varname>
533 above. Use of this setting is
534 optional. After the commands configured
535 in this option are run, all processes
536 remaining for a service are
537 terminated according to the
538 <varname>KillMode=</varname> setting
540 <citerefentry><refentrytitle>systemd.kill</refentrytitle><manvolnum>5</manvolnum></citerefentry>). If
541 this option is not specified, the
542 process is terminated immediately when
543 service stop is requested. Specifier
544 and environment variable substitution
545 is supported (including
546 <varname>$MAINPID</varname>, see
547 above).</para></listitem>
551 <term><varname>ExecStopPost=</varname></term>
552 <listitem><para>Additional commands
553 that are executed after the service
554 was stopped. This includes cases where
555 the commands configured in
556 <varname>ExecStop=</varname> were used,
557 where the service does not have any
558 <varname>ExecStop=</varname> defined, or
559 where the service exited unexpectedly. This
560 argument takes multiple command lines,
561 following the same scheme as described
562 for <varname>ExecStart</varname>. Use
564 optional. Specifier and environment
565 variable substitution is
566 supported.</para></listitem>
570 <term><varname>RestartSec=</varname></term>
571 <listitem><para>Configures the time to
572 sleep before restarting a service (as
574 <varname>Restart=</varname>). Takes a
575 unit-less value in seconds, or a time
576 span value such as "5min
578 100ms.</para></listitem>
582 <term><varname>TimeoutStartSec=</varname></term>
583 <listitem><para>Configures the time to
584 wait for start-up. If a
585 daemon service does not signal
586 start-up completion within the
587 configured time, the service will be
588 considered failed and will be shut
590 Takes a unit-less value in seconds, or a
591 time span value such as "5min
592 20s". Pass <literal>0</literal> to
593 disable the timeout logic. Defaults to
594 <varname>TimeoutStartSec=</varname> from
595 the manager configuration file, except
596 when <varname>Type=oneshot</varname> is
597 used, in which case the timeout
598 is disabled by default.
603 <term><varname>TimeoutStopSec=</varname></term>
604 <listitem><para>Configures the time to
605 wait for stop. If a service is asked
606 to stop, but does not terminate in the
607 specified time, it will be terminated
608 forcibly via <constant>SIGTERM</constant>,
609 and after another timeout of equal duration
610 with <constant>SIGKILL</constant> (see
611 <varname>KillMode=</varname>
612 in <citerefentry><refentrytitle>systemd.kill</refentrytitle><manvolnum>5</manvolnum></citerefentry>).
613 Takes a unit-less value in seconds, or a
614 time span value such as "5min
615 20s". Pass <literal>0</literal> to disable
616 the timeout logic. Defaults to
617 <varname>TimeoutStartSec=</varname> from the
618 manager configuration file.
623 <term><varname>TimeoutSec=</varname></term>
624 <listitem><para>A shorthand for configuring
625 both <varname>TimeoutStartSec=</varname>
626 and <varname>TimeoutStopSec=</varname>
627 to the specified value.
632 <term><varname>WatchdogSec=</varname></term>
633 <listitem><para>Configures the
634 watchdog timeout for a service. The
635 watchdog is activated when the start-up is
636 completed. The service must call
637 <citerefentry><refentrytitle>sd_notify</refentrytitle><manvolnum>3</manvolnum></citerefentry>
638 regularly with <literal>WATCHDOG=1</literal>
639 (i.e. the "keep-alive ping"). If the time
640 between two such calls is larger than
641 the configured time, then the service
642 is placed in a failed state. By
643 setting <varname>Restart=</varname> to
644 <option>on-failure</option> or
645 <option>always</option>, the service
646 will be automatically restarted. The
647 time configured here will be passed to
648 the executed service process in the
649 <varname>WATCHDOG_USEC=</varname>
650 environment variable. This allows
651 daemons to automatically enable the
652 keep-alive pinging logic if watchdog
653 support is enabled for the service. If
655 <varname>NotifyAccess=</varname> (see
656 below) should be set to open access to
657 the notification socket provided by
659 <varname>NotifyAccess=</varname> is
660 not set, it will be implicitly set to
661 <option>main</option>. Defaults to 0,
663 feature.</para></listitem>
667 <term><varname>Restart=</varname></term>
668 <listitem><para>Configures whether the
669 service shall be restarted when the
670 service process exits, is killed,
671 or a timeout is reached. The service
672 process may be the main service
673 process, but it may also be one of the
674 processes specified with
675 <varname>ExecStartPre=</varname>,
676 <varname>ExecStartPost=</varname>,
677 <varname>ExecStop=</varname>,
678 <varname>ExecStopPost=</varname>, or
679 <varname>ExecReload=</varname>.
680 When the death of the process is a
681 result of systemd operation (e.g. service
682 stop or restart), the service will not be
683 restarted. Timeouts include missing
684 the watchdog "keep-alive ping"
685 deadline and a service start, reload,
686 and stop operation timeouts.</para>
690 <option>on-success</option>,
691 <option>on-failure</option>,
692 <option>on-watchdog</option>,
693 <option>on-abort</option>, or
694 <option>always</option>. If set to
695 <option>no</option> (the default), the
696 service will not be restarted. If set to
697 <option>on-success</option>, it will be
698 restarted only when the service process
700 In this context, a clean exit means
701 an exit code of 0, or one of the signals
702 <constant>SIGHUP</constant>,
703 <constant>SIGINT</constant>,
704 <constant>SIGTERM</constant>,
705 or <constant>SIGPIPE</constant>, and
706 additionally, exit statuses and signals
707 specified in <varname>SuccessExitStatus=</varname>.
708 If set to <option>on-failure</option>,
709 the service will be restarted when the
710 process exits with a non-zero exit code,
711 is terminated by a signal (including on
712 core dump), when an operation (such as
713 service reload) times out, and when the
714 configured watchdog timeout is triggered.
716 <option>on-abort</option>, the service
717 will be restarted only if the service
718 process exits due to an uncaught
719 signal not specified as a clean exit
722 <option>on-watchdog</option>, the service
723 will be restarted only if the watchdog
724 timeout for the service expires.
726 <option>always</option>, the service
727 will be restarted regardless of whether
728 it exited cleanly or not, got
729 terminated abnormally by a signal, or
730 hit a timeout.</para>
732 <para>In addition to the above settings,
733 the service will not be restarted if the
734 exit code or signal is specified in
735 <varname>RestartPreventExitStatus=</varname>
736 (see below).</para></listitem>
740 <term><varname>SuccessExitStatus=</varname></term>
741 <listitem><para>Takes a list of exit
742 status definitions that when returned
743 by the main service process will be
744 considered successful termination, in
745 addition to the normal successful exit
746 code 0 and the signals <constant>SIGHUP</constant>, <constant>SIGINT</constant>,
747 <constant>SIGTERM</constant>, and <constant>SIGPIPE</constant>. Exit status
748 definitions can either be numeric exit
749 codes or termination signal names,
750 separated by spaces. For example:
751 <programlisting>SuccessExitStatus=1 2 8 <constant>SIGKILL</constant></programlisting>
752 ensures that exit codes 1, 2, 8 and
753 the termination signal
754 <constant>SIGKILL</constant> are
755 considered clean service terminations.
758 <para>Note that if a process has a
759 signal handler installed and exits by
761 <citerefentry><refentrytitle>_exit</refentrytitle><manvolnum>2</manvolnum></citerefentry>
762 in response to a signal, the
763 information about the signal is lost.
764 Programs should instead perform cleanup and kill themselves with the same signal instead. See
765 <ulink url="http://www.cons.org/cracauer/sigint.html">Proper handling of SIGINT/SIGQUIT — How to be a proper program</ulink>.</para>
767 <para>This option may appear more than once,
768 in which case the list of successful
769 exit statuses is merged. If the empty
770 string is assigned to this option, the
771 list is reset, all prior assignments
772 of this option will have no
773 effect.</para></listitem>
777 <term><varname>RestartPreventExitStatus=</varname></term>
778 <listitem><para>Takes a list of exit
779 status definitions that when returned
780 by the main service process will
781 prevent automatic service restarts,
782 regardless of the restart setting
784 <varname>Restart=</varname>. Exit
785 status definitions can either be
786 numeric exit codes or termination
787 signal names, and are separated by
788 spaces. Defaults to the empty list, so
789 that, by default, no exit status is
790 excluded from the configured restart
792 <literal>RestartPreventExitStatus=1 6
793 SIGABRT</literal>, ensures that exit
794 codes 1 and 6 and the termination
795 signal <constant>SIGABRT</constant> will
796 not result in automatic service
798 option may appear more than once, in
799 which case the list of restart-preventing
800 statuses is merged. If the empty
801 string is assigned to this option, the
802 list is reset and all prior assignments
803 of this option will have no
804 effect.</para></listitem>
808 <term><varname>PermissionsStartOnly=</varname></term>
809 <listitem><para>Takes a boolean
810 argument. If true, the permission-related
811 execution options, as
813 <varname>User=</varname> and similar
815 <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>
816 for more information), are only applied
817 to the process started with
818 <varname>ExecStart=</varname>, and not
820 <varname>ExecStartPre=</varname>,
821 <varname>ExecStartPost=</varname>,
822 <varname>ExecReload=</varname>,
823 <varname>ExecStop=</varname>, and
824 <varname>ExecStopPost=</varname>
825 commands. If false, the setting is
826 applied to all configured commands the
827 same way. Defaults to
828 false.</para></listitem>
832 <term><varname>RootDirectoryStartOnly=</varname></term>
833 <listitem><para>Takes a boolean
834 argument. If true, the root directory,
835 as configured with the
836 <varname>RootDirectory=</varname>
838 <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>
839 for more information), is only applied
840 to the process started with
841 <varname>ExecStart=</varname>, and not
843 <varname>ExecStartPre=</varname>,
844 <varname>ExecStartPost=</varname>,
845 <varname>ExecReload=</varname>,
846 <varname>ExecStop=</varname>, and
847 <varname>ExecStopPost=</varname>
848 commands. If false, the setting is
849 applied to all configured commands the
850 same way. Defaults to
851 false.</para></listitem>
855 <term><varname>NonBlocking=</varname></term>
856 <listitem><para>Set the
857 <constant>O_NONBLOCK</constant> flag
858 for all file descriptors passed via
859 socket-based activation. If true, all
860 file descriptors >= 3 (i.e. all except
861 stdin, stdout, and stderr) will have
862 the <constant>O_NONBLOCK</constant> flag
864 non-blocking mode. This option is only
865 useful in conjunction with a socket
866 unit, as described in
867 <citerefentry><refentrytitle>systemd.socket</refentrytitle><manvolnum>5</manvolnum></citerefentry>. Defaults
868 to false.</para></listitem>
872 <term><varname>NotifyAccess=</varname></term>
873 <listitem><para>Controls access to the
874 service status notification socket, as
876 <citerefentry><refentrytitle>sd_notify</refentrytitle><manvolnum>3</manvolnum></citerefentry>
878 <option>none</option> (the default),
879 <option>main</option> or
880 <option>all</option>. If
881 <option>none</option>, no daemon status
882 updates are accepted from the service
883 processes, all status update messages
884 are ignored. If <option>main</option>,
885 only service updates sent from the
886 main process of the service are
887 accepted. If <option>all</option>, all
888 services updates from all members of
889 the service's control group are
890 accepted. This option should be set to
891 open access to the notification socket
893 <varname>Type=notify</varname> or
894 <varname>WatchdogSec=</varname> (see
895 above). If those options are used but
896 <varname>NotifyAccess=</varname> is not
897 configured, it will be implicitly set
899 <option>main</option>.</para></listitem>
903 <term><varname>Sockets=</varname></term>
904 <listitem><para>Specifies the name of
905 the socket units this service shall
906 inherit the sockets from when the
907 service is started. Normally it
908 should not be necessary to use this
909 setting as all sockets whose unit
910 shares the same name as the service
911 (ignoring the different suffix of course)
912 are passed to the spawned
915 <para>Note that the same socket may be
916 passed to multiple processes at the
917 same time. Also note that a different
918 service may be activated on incoming
919 traffic than that which inherits the
920 sockets. Or in other words: the
921 <varname>Service=</varname> setting of
922 <filename>.socket</filename> units
923 does not have to match the inverse of
924 the <varname>Sockets=</varname>
926 <filename>.service</filename> it
929 <para>This option may appear more than
930 once, in which case the list of socket
931 units is merged. If the empty string
932 is assigned to this option, the list of
933 sockets is reset, and all prior uses of
934 this setting will have no
935 effect.</para></listitem>
939 <term><varname>StartLimitInterval=</varname></term>
940 <term><varname>StartLimitBurst=</varname></term>
942 <listitem><para>Configure service
943 start rate limiting. By default,
944 services which are started more
945 than 5 times within 10 seconds are not
946 permitted to start any more times
947 until the 10 second interval ends. With
948 these two options, this rate limiting
950 <varname>StartLimitInterval=</varname>
951 to configure the checking interval (defaults to
952 <varname>DefaultStartLimitInterval=</varname> in
953 manager configuration file, set to 0 to disable
954 any kind of rate limiting). Use
955 <varname>StartLimitBurst=</varname> to
956 configure how many starts per interval
957 are allowed (defaults to
958 <varname>DefaultStartLimitBurst=</varname> in
959 manager configuration file). These
960 configuration options are particularly
961 useful in conjunction with
962 <varname>Restart=</varname>; however,
963 they apply to all kinds of starts
964 (including manual), not just those
966 <varname>Restart=</varname> logic.
967 Note that units which are configured
968 for <varname>Restart=</varname> and
969 which reach the start limit are not
970 attempted to be restarted anymore;
971 however, they may still be restarted
972 manually at a later point, from which
973 point on, the restart logic is again
976 reset-failed</command> will cause the
977 restart rate counter for a service to
978 be flushed, which is useful if the
979 administrator wants to manually start
980 a service and the start limit
982 that.</para></listitem>
986 <term><varname>StartLimitAction=</varname></term>
988 <listitem><para>Configure the action
989 to take if the rate limit configured
991 <varname>StartLimitInterval=</varname>
993 <varname>StartLimitBurst=</varname> is
995 <option>none</option>,
996 <option>reboot</option>,
997 <option>reboot-force</option>, or
998 <option>reboot-immediate</option>. If
999 <option>none</option> is set,
1000 hitting the rate limit will trigger no
1001 action besides that the start will not
1002 be permitted. <option>reboot</option>
1003 causes a reboot following the normal
1004 shutdown procedure (i.e. equivalent to
1005 <command>systemctl reboot</command>).
1006 <option>reboot-force</option> causes
1007 a forced reboot which will terminate
1008 all processes forcibly but should
1009 cause no dirty file systems on reboot
1010 (i.e. equivalent to <command>systemctl
1011 reboot -f</command>) and
1012 <option>reboot-immediate</option>
1013 causes immediate execution of the
1014 <citerefentry><refentrytitle>reboot</refentrytitle><manvolnum>2</manvolnum></citerefentry>
1015 system call, which might result in
1016 data loss. Defaults to
1017 <option>none</option>.</para></listitem>
1023 <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>
1025 <citerefentry><refentrytitle>systemd.kill</refentrytitle><manvolnum>5</manvolnum></citerefentry>
1026 for more settings.</para>
1031 <title>Compatibility Options</title>
1033 <para>The following options are also available in the
1034 <literal>[Service]</literal> section, but exist purely
1035 for compatibility reasons and should not be used in
1036 newly written service files.</para>
1038 <variablelist class='unit-directives'>
1040 <term><varname>SysVStartPriority=</varname></term>
1041 <listitem><para>Set the SysV start
1042 priority to use to order this service
1043 in relation to SysV services lacking
1044 LSB headers. This option is only
1045 necessary to fix ordering in relation
1046 to legacy SysV services that have no
1047 ordering information encoded in the
1048 script headers. As such, it should only
1049 be used as a temporary compatibility
1050 option and should not be used in new unit
1051 files. Almost always, it is a better
1052 choice to add explicit ordering
1054 <varname>After=</varname> or
1055 <varname>Before=</varname>,
1056 instead. For more details, see
1057 <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>.
1058 If used, pass an integer value in the
1059 range 0-99.</para></listitem>
1065 <title>See Also</title>
1067 <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
1068 <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
1069 <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
1070 <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
1071 <citerefentry><refentrytitle>systemd.resource-control</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
1072 <citerefentry><refentrytitle>systemd.kill</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
1073 <citerefentry><refentrytitle>systemd.directives</refentrytitle><manvolnum>7</manvolnum></citerefentry>