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9   Copyright 2010 Lennart Poettering
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24
25 <refentry id="systemd.service">
26         <refentryinfo>
27                 <title>systemd.service</title>
28                 <productname>systemd</productname>
29
30                 <authorgroup>
31                         <author>
32                                 <contrib>Developer</contrib>
33                                 <firstname>Lennart</firstname>
34                                 <surname>Poettering</surname>
35                                 <email>lennart@poettering.net</email>
36                         </author>
37                 </authorgroup>
38         </refentryinfo>
39
40         <refmeta>
41                 <refentrytitle>systemd.service</refentrytitle>
42                 <manvolnum>5</manvolnum>
43         </refmeta>
44
45         <refnamediv>
46                 <refname>systemd.service</refname>
47                 <refpurpose>systemd service configuration files</refpurpose>
48         </refnamediv>
49
50         <refsynopsisdiv>
51                 <para><filename>systemd.service</filename></para>
52         </refsynopsisdiv>
53
54         <refsect1>
55                 <title>Description</title>
56
57                 <para>A unit configuration file whose name ends in
58                 <filename>.service</filename> encodes information
59                 about a process controlled and supervised by
60                 systemd.</para>
61
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>
71
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.</para>
76
77                 <para>Unless <varname>DefaultDependencies=</varname>
78                 is set to <option>false</option>, service units will
79                 implicitly have dependencies of type
80                 <varname>Requires=</varname> and
81                 <varname>After=</varname> on
82                 <filename>basic.target</filename> as well as
83                 dependencies of type <varname>Conflicts=</varname> and
84                 <varname>Before=</varname> on
85                 <filename>shutdown.target</filename>. These ensure
86                 that normal service units pull in basic system
87                 initialization, and are terminated cleanly prior to
88                 system shutdown. Only services involved with early
89                 boot or late system shutdown should disable this
90                 option.</para>
91
92                 <para>If a service is requested under a certain name
93                 but no unit configuration file is found, systemd looks
94                 for a SysV init script by the same name (with the
95                 <filename>.service</filename> suffix removed) and
96                 dynamically creates a service unit from that
97                 script. This is useful for compatibility with
98                 SysV.</para>
99         </refsect1>
100
101         <refsect1>
102                 <title>Options</title>
103
104                 <para>Service files must include a
105                 <literal>[Service]</literal> section, which carries
106                 information about the service and the process it
107                 supervises. A number of options that may be used in
108                 this section are shared with other unit types. These
109                 options are documented in
110                 <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>. The
111                 options specific to the <literal>[Service]</literal>
112                 section of service units are the following:</para>
113
114                 <variablelist>
115                         <varlistentry>
116                                 <term><varname>Type=</varname></term>
117
118                                 <listitem><para>Configures the process
119                                 start-up type for this service
120                                 unit. One of <option>simple</option>,
121                                 <option>forking</option>,
122                                 <option>oneshot</option>,
123                                 <option>dbus</option>,
124                                 <option>notify</option> or
125                                 <option>idle</option>.</para>
126
127                                 <para>If set to
128                                 <option>simple</option> (the default
129                                 value) it is expected that the process
130                                 configured with
131                                 <varname>ExecStart=</varname> is the
132                                 main process of the service. In this
133                                 mode, if the process offers
134                                 functionality to other processes on
135                                 the system its communication channels
136                                 should be installed before the daemon
137                                 is started up (e.g. sockets set up by
138                                 systemd, via socket activation), as
139                                 systemd will immediately proceed
140                                 starting follow-up units.</para>
141
142                                 <para>If set to
143                                 <option>forking</option> it is
144                                 expected that the process configured
145                                 with <varname>ExecStart=</varname>
146                                 will call <function>fork()</function>
147                                 as part of its start-up. The parent process is
148                                 expected to exit when start-up is
149                                 complete and all communication
150                                 channels set up. The child continues
151                                 to run as the main daemon
152                                 process. This is the behaviour of
153                                 traditional UNIX daemons. If this
154                                 setting is used, it is recommended to
155                                 also use the
156                                 <varname>PIDFile=</varname> option, so
157                                 that systemd can identify the main
158                                 process of the daemon. systemd will
159                                 proceed starting follow-up units as
160                                 soon as the parent process
161                                 exits.</para>
162
163                                 <para>Behaviour of
164                                 <option>oneshot</option> is similar
165                                 to <option>simple</option>, however
166                                 it is expected that the process has to
167                                 exit before systemd starts follow-up
168                                 units. <varname>RemainAfterExit=</varname>
169                                 is particularly useful for this type
170                                 of service.</para>
171
172                                 <para>Behaviour of
173                                 <option>dbus</option> is similar to
174                                 <option>simple</option>, however it is
175                                 expected that the daemon acquires a
176                                 name on the D-Bus bus, as configured
177                                 by
178                                 <varname>BusName=</varname>. systemd
179                                 will proceed starting follow-up units
180                                 after the D-Bus bus name has been
181                                 acquired. Service units with this
182                                 option configured implicitly gain
183                                 dependencies on the
184                                 <filename>dbus.socket</filename>
185                                 unit.</para>
186
187                                 <para>Behaviour of
188                                 <option>notify</option> is similar to
189                                 <option>simple</option>, however it is
190                                 expected that the daemon sends a
191                                 notification message via
192                                 <citerefentry><refentrytitle>sd_notify</refentrytitle><manvolnum>3</manvolnum></citerefentry>
193                                 or an equivalent call when it finished
194                                 starting up. systemd will proceed
195                                 starting follow-up units after this
196                                 notification message has been sent. If
197                                 this option is used
198                                 <varname>NotifyAccess=</varname> (see
199                                 below) should be set to open access to
200                                 the notification socket provided by
201                                 systemd. If
202                                 <varname>NotifyAccess=</varname> is
203                                 not set, it will be implicitly set to
204                                 <option>main</option>.</para>
205
206                                 <para>Behaviour of
207                                 <option>idle</option> is very similar
208                                 to <option>simple</option>, however
209                                 actual execution of a the service
210                                 binary is delayed until all jobs are
211                                 dispatched. This may be used to avoid
212                                 interleaving of output of shell
213                                 services with the status output on the
214                                 console.</para>
215                                 </listitem>
216                         </varlistentry>
217
218                         <varlistentry>
219                                 <term><varname>RemainAfterExit=</varname></term>
220
221                                 <listitem><para>Takes a boolean value
222                                 that specifies whether the service
223                                 shall be considered active even when
224                                 all its processes exited. Defaults to
225                                 <option>no</option>.</para>
226                                 </listitem>
227                         </varlistentry>
228
229                         <varlistentry>
230                                 <term><varname>GuessMainPID=</varname></term>
231
232                                 <listitem><para>Takes a boolean value
233                                 that specifies whether systemd should
234                                 try to guess the main PID of a service
235                                 should if it cannot be determined
236                                 reliably. This option is ignored
237                                 unless <option>Type=forking</option>
238                                 is set and <option>PIDFile=</option>
239                                 is unset because for the other types
240                                 or with an explicitly configured PID
241                                 file the main PID is always known. The
242                                 guessing algorithm might come to
243                                 incorrect conclusions if a daemon
244                                 consists of more than one process. If
245                                 the main PID cannot be determined
246                                 failure detection and automatic
247                                 restarting of a service will not work
248                                 reliably. Defaults to
249                                 <option>yes</option>.</para>
250                                 </listitem>
251                         </varlistentry>
252
253                         <varlistentry>
254                                 <term><varname>PIDFile=</varname></term>
255
256                                 <listitem><para>Takes an absolute file
257                                 name pointing to the PID file of this
258                                 daemon. Use of this option is
259                                 recommended for services where
260                                 <varname>Type=</varname> is set to
261                                 <option>forking</option>. systemd will
262                                 read the PID of the main process of
263                                 the daemon after start-up of the
264                                 service. systemd will not write to the
265                                 file configured here.</para>
266                                 </listitem>
267                         </varlistentry>
268
269                         <varlistentry>
270                                 <term><varname>BusName=</varname></term>
271
272                                 <listitem><para>Takes a D-Bus bus
273                                 name, where this service is reachable
274                                 as. This option is mandatory for
275                                 services where
276                                 <varname>Type=</varname> is set to
277                                 <option>dbus</option>, but its use
278                                 is otherwise recommended as well if
279                                 the process takes a name on the D-Bus
280                                 bus.</para>
281                                 </listitem>
282                         </varlistentry>
283
284                         <varlistentry>
285                                 <term><varname>ExecStart=</varname></term>
286                                 <listitem><para>Takes a command line
287                                 that is executed when this service
288                                 shall be started up. The first token
289                                 of the command line must be an
290                                 absolute file name, then followed by
291                                 arguments for the process. It is
292                                 mandatory to set this option for all
293                                 services. This option may not be
294                                 specified more than once, except when
295                                 <varname>Type=oneshot</varname> is
296                                 used in which case more than one
297                                 <varname>ExecStart=</varname> line is
298                                 accepted which are then invoked one by
299                                 one, sequentially in the order they
300                                 appear in the unit file.</para>
301
302                                 <para>Optionally, if the absolute file
303                                 name is prefixed with
304                                 <literal>@</literal>, the second token
305                                 will be passed as
306                                 <literal>argv[0]</literal> to the
307                                 executed process, followed by the
308                                 further arguments specified. If the
309                                 first token is prefixed with
310                                 <literal>-</literal> an exit code of
311                                 the command normally considered a
312                                 failure (i.e. non-zero exit status or
313                                 abnormal exit due to signal) is ignored
314                                 and considered success. If both
315                                 <literal>-</literal> and
316                                 <literal>@</literal> are used for the
317                                 same command the former must precede
318                                 the latter. Unless
319                                 <varname>Type=forking</varname> is
320                                 set, the process started via this
321                                 command line will be considered the
322                                 main process of the daemon. The
323                                 command line accepts % specifiers as
324                                 described in
325                                 <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para>
326
327                                 <para>On top of that basic environment
328                                 variable substitution is
329                                 supported. Use
330                                 <literal>${FOO}</literal> as part of a
331                                 word, or as word of its own on the
332                                 command line, in which case it will be
333                                 replaced by the value of the
334                                 environment variable including all
335                                 whitespace it contains, resulting in a
336                                 single argument.  Use
337                                 <literal>$FOO</literal> as a separate
338                                 word on the command line, in which
339                                 case it will be replaced by the value
340                                 of the environment variable split up
341                                 at whitespace, resulting in no or more
342                                 arguments. Note that the first
343                                 argument (i.e. the program to execute)
344                                 may not be a variable, and must be a
345                                 literal and absolute path
346                                 name.</para></listitem>
347                         </varlistentry>
348
349                         <varlistentry>
350                                 <term><varname>ExecStartPre=</varname></term>
351                                 <term><varname>ExecStartPost=</varname></term>
352                                 <listitem><para>Additional commands
353                                 that are executed before (resp. after)
354                                 the command in
355                                 <varname>ExecStart=</varname>. Multiple
356                                 command lines may be concatenated in a
357                                 single directive, by separating them
358                                 by semicolons (these semicolons must
359                                 be passed as separate words). In that
360                                 case, the commands are executed one
361                                 after the other,
362                                 serially. Alternatively, these
363                                 directives may be specified more than
364                                 once with the same effect. However,
365                                 the latter syntax is not recommended
366                                 for compatibility with parsers
367                                 suitable for XDG
368                                 <filename>.desktop</filename> files.
369                                 Use of these settings is
370                                 optional. Specifier and environment
371                                 variable substitution is
372                                 supported.</para></listitem>
373                         </varlistentry>
374
375                         <varlistentry>
376                                 <term><varname>ExecReload=</varname></term>
377                                 <listitem><para>Commands to execute to
378                                 trigger a configuration reload in the
379                                 service. This argument takes multiple
380                                 command lines, following the same
381                                 scheme as pointed out for
382                                 <varname>ExecStartPre=</varname>
383                                 above. Use of this setting is
384                                 optional. Specifier and environment
385                                 variable substitution is supported
386                                 here following the same scheme as for
387                                 <varname>ExecStart=</varname>. One
388                                 special environment variable is set:
389                                 if known <literal>$MAINPID</literal> is
390                                 set to the main process of the
391                                 daemon, and may be used for command
392                                 lines like the following:
393                                 <command>/bin/kill -HUP
394                                 $MAINPID</command>.</para></listitem>
395                         </varlistentry>
396
397                         <varlistentry>
398                                 <term><varname>ExecStop=</varname></term>
399                                 <listitem><para>Commands to execute to
400                                 stop the service started via
401                                 <varname>ExecStart=</varname>. This
402                                 argument takes multiple command lines,
403                                 following the same scheme as pointed
404                                 out for
405                                 <varname>ExecStartPre=</varname>
406                                 above. Use of this setting is
407                                 optional. All processes remaining for
408                                 a service after the commands
409                                 configured in this option are run are
410                                 terminated according to the
411                                 <varname>KillMode=</varname> setting
412                                 (see below). If this option is not
413                                 specified the process is terminated
414                                 right-away when service stop is
415                                 requested. Specifier and environment
416                                 variable substitution is supported
417                                 (including
418                                 <literal>$MAINPID</literal>, see
419                                 above).</para></listitem>
420                         </varlistentry>
421
422                         <varlistentry>
423                                 <term><varname>ExecStopPost=</varname></term>
424                                 <listitem><para>Additional commands
425                                 that are executed after the service
426                                 was stopped using the commands
427                                 configured in
428                                 <varname>ExecStop=</varname>. This
429                                 argument takes multiple command lines,
430                                 following the same scheme as pointed
431                                 out for
432                                 <varname>ExecStartPre</varname>. Use
433                                 of these settings is
434                                 optional. Specifier and environment
435                                 variable substitution is
436                                 supported.</para></listitem>
437                         </varlistentry>
438
439                         <varlistentry>
440                                 <term><varname>RestartSec=</varname></term>
441                                 <listitem><para>Configures the time to
442                                 sleep before restarting a service (as
443                                 configured with
444                                 <varname>Restart=</varname>). Takes a
445                                 unit-less value in seconds, or a time
446                                 span value such as "5min
447                                 20s". Defaults to
448                                 100ms.</para></listitem>
449                         </varlistentry>
450
451                         <varlistentry>
452                                 <term><varname>TimeoutSec=</varname></term>
453                                 <listitem><para>Configures the time to
454                                 wait for start-up and stop. If a
455                                 daemon service does not signal
456                                 start-up completion within the
457                                 configured time the service will be
458                                 considered failed and be shut down
459                                 again. If a service is asked to stop
460                                 but does not terminate in the
461                                 specified time it will be terminated
462                                 forcibly via SIGTERM, and after
463                                 another delay of this time with
464                                 SIGKILL. (See
465                                 <varname>KillMode=</varname>
466                                 below.) Takes a unit-less value in seconds, or a
467                                 time span value such as "5min
468                                 20s". Pass 0 to disable the timeout
469                                 logic. Defaults to
470                                 90s.</para></listitem>
471                         </varlistentry>
472
473                         <varlistentry>
474                                 <term><varname>WatchdogSec=</varname></term>
475                                 <listitem><para>Configures the
476                                 watchdog timeout for a service. This
477                                 is activated when the start-up is
478                                 completed. The service must call
479                                 <citerefentry><refentrytitle>sd_notify</refentrytitle><manvolnum>3</manvolnum></citerefentry>
480                                 regularly with "WATCHDOG=1". If the
481                                 time between two such calls is larger
482                                 than the configured time then the
483                                 service is placed in a failure
484                                 state. By setting
485                                 <varname>Restart=</varname>
486                                 to <option>on-failure</option> or
487                                 <option>always</option> the service
488                                 will be automatically restarted. The
489                                 time configured here will be passed to
490                                 the executed service process in the
491                                 <varname>WATCHDOG_USEC=</varname>
492                                 environment variable. If
493                                 this option is used
494                                 <varname>NotifyAccess=</varname> (see
495                                 below) should be set to open access to
496                                 the notification socket provided by
497                                 systemd. If
498                                 <varname>NotifyAccess=</varname> is not
499                                 set, it will be implicitly set to
500                                 <option>main</option>. Defaults to 0,
501                                 which disables this
502                                 feature.</para></listitem>
503                         </varlistentry>
504
505                         <varlistentry>
506                                 <term><varname>Restart=</varname></term>
507                                 <listitem><para>Configures whether the
508                                 main service process shall be
509                                 restarted when it exits. Takes one of
510                                 <option>no</option>,
511                                 <option>on-success</option>,
512                                 <option>on-failure</option>,
513                                 <option>on-abort</option> or
514                                 <option>always</option>. If set to
515                                 <option>no</option> (the default) the
516                                 service will not be restarted when it
517                                 exits. If set to
518                                 <option>on-success</option> it will be
519                                 restarted only when it exited cleanly,
520                                 i.e. terminated with an exit code of
521                                 0. If set to
522                                 <option>on-failure</option> it will be
523                                 restarted only when it exited with an
524                                 exit code not equalling 0, when
525                                 terminated by a signal, when an
526                                 operation times out or when the
527                                 configured watchdog timeout is
528                                 triggered. If set to
529                                 <option>on-abort</option> it will be
530                                 restarted only if it exits due to
531                                 reception of an uncaught signal. If
532                                 set to <option>always</option> the
533                                 service will be restarted regardless
534                                 whether it exited cleanly or not,
535                                 got terminated abnormally by a
536                                 signal or hit a timeout.</para></listitem>
537                         </varlistentry>
538
539                         <varlistentry>
540                                 <term><varname>PermissionsStartOnly=</varname></term>
541                                 <listitem><para>Takes a boolean
542                                 argument. If true, the permission
543                                 related execution options as
544                                 configured with
545                                 <varname>User=</varname> and similar
546                                 options (see
547                                 <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>
548                                 for more information) are only applied
549                                 to the process started with
550                                 <varname>ExecStart=</varname>, and not
551                                 to the various other
552                                 <varname>ExecStartPre=</varname>,
553                                 <varname>ExecStartPost=</varname>,
554                                 <varname>ExecReload=</varname>,
555                                 <varname>ExecStop=</varname>,
556                                 <varname>ExecStopPost=</varname>
557                                 commands. If false, the setting is
558                                 applied to all configured commands the
559                                 same way. Defaults to
560                                 false.</para></listitem>
561                         </varlistentry>
562
563                         <varlistentry>
564                                 <term><varname>RootDirectoryStartOnly=</varname></term>
565                                 <listitem><para>Takes a boolean
566                                 argument. If true, the root directory
567                                 as configured with the
568                                 <varname>RootDirectory=</varname>
569                                 option (see
570                                 <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>
571                                 for more information) is only applied
572                                 to the process started with
573                                 <varname>ExecStart=</varname>, and not
574                                 to the various other
575                                 <varname>ExecStartPre=</varname>,
576                                 <varname>ExecStartPost=</varname>,
577                                 <varname>ExecReload=</varname>,
578                                 <varname>ExecStop=</varname>,
579                                 <varname>ExecStopPost=</varname>
580                                 commands. If false, the setting is
581                                 applied to all configured commands the
582                                 same way. Defaults to
583                                 false.</para></listitem>
584                         </varlistentry>
585
586                         <varlistentry>
587                                 <term><varname>SysVStartPriority=</varname></term>
588                                 <listitem><para>Set the SysV start
589                                 priority to use to order this service
590                                 in relation to SysV services lacking
591                                 LSB headers. This option is only
592                                 necessary to fix ordering in relation
593                                 to legacy SysV services, that have no
594                                 ordering information encoded in the
595                                 script headers. As such it should only
596                                 be used as temporary compatibility
597                                 option, and not be used in new unit
598                                 files. Almost always it is a better
599                                 choice to add explicit ordering
600                                 directives via
601                                 <varname>After=</varname> or
602                                 <varname>Before=</varname>,
603                                 instead. For more details see
604                                 <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>. If
605                                 used, pass an integer value in the
606                                 range 0-99.</para></listitem>
607                         </varlistentry>
608
609                         <varlistentry>
610                                 <term><varname>KillMode=</varname></term>
611                                 <listitem><para>Specifies how
612                                 processes of this service shall be
613                                 killed. One of
614                                 <option>control-group</option>,
615                                 <option>process</option>,
616                                 <option>none</option>.</para>
617
618                                 <para>If set to
619                                 <option>control-group</option> all
620                                 remaining processes in the control
621                                 group of this service will be
622                                 terminated on service stop, after the
623                                 stop command (as configured with
624                                 <varname>ExecStop=</varname>) is
625                                 executed. If set to
626                                 <option>process</option> only the main
627                                 process itself is killed. If set to
628                                 <option>none</option> no process is
629                                 killed. In this case only the stop
630                                 command will be executed on service
631                                 stop, but no process be killed
632                                 otherwise. Processes remaining alive
633                                 after stop are left in their control
634                                 group and the control group continues
635                                 to exist after stop unless it is
636                                 empty. Defaults to
637                                 <option>control-group</option>.</para>
638
639                                 <para>Processes will first be
640                                 terminated via SIGTERM (unless the
641                                 signal to send is changed via
642                                 <varname>KillSignal=</varname>). If
643                                 then after a delay (configured via the
644                                 <varname>TimeoutSec=</varname> option)
645                                 processes still remain, the
646                                 termination request is repeated with
647                                 the SIGKILL signal (unless this is
648                                 disabled via the
649                                 <varname>SendSIGKILL=</varname>
650                                 option). See
651                                 <citerefentry><refentrytitle>kill</refentrytitle><manvolnum>2</manvolnum></citerefentry>
652                                 for more
653                                 information.</para></listitem>
654                         </varlistentry>
655
656                         <varlistentry>
657                                 <term><varname>KillSignal=</varname></term>
658                                 <listitem><para>Specifies which signal
659                                 to use when killing a
660                                 service. Defaults to SIGTERM.
661                                 </para></listitem>
662                         </varlistentry>
663
664                         <varlistentry>
665                                 <term><varname>SendSIGKILL=</varname></term>
666                                 <listitem><para>Specifies whether to
667                                 send SIGKILL to remaining processes
668                                 after a timeout, if the normal
669                                 shutdown procedure left processes of
670                                 the service around. Takes a boolean
671                                 value. Defaults to "yes".
672                                 </para></listitem>
673                         </varlistentry>
674
675                         <varlistentry>
676                                 <term><varname>NonBlocking=</varname></term>
677                                 <listitem><para>Set O_NONBLOCK flag
678                                 for all file descriptors passed via
679                                 socket-based activation. If true, all
680                                 file descriptors >= 3 (i.e. all except
681                                 STDIN/STDOUT/STDERR) will have
682                                 the O_NONBLOCK flag set and hence are in
683                                 non-blocking mode. This option is only
684                                 useful in conjunction with a socket
685                                 unit, as described in
686                                 <citerefentry><refentrytitle>systemd.socket</refentrytitle><manvolnum>5</manvolnum></citerefentry>. Defaults
687                                 to false.</para></listitem>
688                         </varlistentry>
689
690                         <varlistentry>
691                                 <term><varname>NotifyAccess=</varname></term>
692                                 <listitem><para>Controls access to the
693                                 service status notification socket, as
694                                 accessible via the
695                                 <citerefentry><refentrytitle>sd_notify</refentrytitle><manvolnum>3</manvolnum></citerefentry>
696                                 call. Takes one of
697                                 <option>none</option> (the default),
698                                 <option>main</option> or
699                                 <option>all</option>. If
700                                 <option>none</option> no daemon status
701                                 updates are accepted from the service
702                                 processes, all status update messages
703                                 are ignored. If <option>main</option>
704                                 only service updates sent from the
705                                 main process of the service are
706                                 accepted. If <option>all</option> all
707                                 services updates from all members of
708                                 the service's control group are
709                                 accepted. This option should be set to
710                                 open access to the notification socket
711                                 when using
712                                 <varname>Type=notify</varname> or
713                                 <varname>WatchdogUsec=</varname> (see
714                                 above). If those options are used but
715                                 <varname>NotifyAccess=</varname> not
716                                 configured it will be implicitly set
717                                 to
718                                 <option>main</option>.</para></listitem>
719                         </varlistentry>
720
721                         <varlistentry>
722                                 <term><varname>Sockets=</varname></term>
723                                 <listitem><para>Specifies the name of
724                                 the socket units this service shall
725                                 inherit the sockets from when the
726                                 service is started. Normally it
727                                 should not be necessary to use this
728                                 setting as all sockets whose unit
729                                 shares the same name as the service
730                                 (ignoring the different suffix of course)
731                                 are passed to the spawned
732                                 process.</para>
733
734                                 <para>Note that the same socket may be
735                                 passed to multiple processes at the
736                                 same time. Also note that a different
737                                 service may be activated on incoming
738                                 traffic than inherits the sockets. Or
739                                 in other words: The
740                                 <varname>Service=</varname> setting of
741                                 <filename>.socket</filename> units
742                                 doesn't have to match the inverse of the
743                                 <varname>Sockets=</varname> setting of
744                                 the <filename>.service</filename> it
745                                 refers to.</para></listitem>
746                         </varlistentry>
747
748                         <varlistentry>
749                                 <term><varname>FsckPassNo=</varname></term>
750                                 <listitem><para>Set the fsck passno
751                                 priority to use to order this service
752                                 in relation to other file system
753                                 checking services. This option is only
754                                 necessary to fix ordering in relation
755                                 to fsck jobs automatically created for
756                                 all <filename>/etc/fstab</filename>
757                                 entries with a value in the fs_passno
758                                 column > 0. As such it should only be
759                                 used as option for fsck
760                                 services. Almost always it is a better
761                                 choice to add explicit ordering
762                                 directives via
763                                 <varname>After=</varname> or
764                                 <varname>Before=</varname>,
765                                 instead. For more details see
766                                 <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>. If
767                                 used, pass an integer value in the
768                                 same range as
769                                 <filename>/etc/fstab</filename>'s
770                                 fs_passno column. See
771                                 <citerefentry><refentrytitle>fstab</refentrytitle><manvolnum>5</manvolnum></citerefentry>
772                                 for details.</para></listitem>
773                         </varlistentry>
774
775                         <varlistentry>
776                                 <term><varname>StartLimitInterval=</varname></term>
777                                 <term><varname>StartLimitBurst=</varname></term>
778
779                                 <listitem><para>Configure service
780                                 start rate limiting. By default
781                                 services which are started more often
782                                 than 5 times within 10s are not
783                                 permitted to start any more times
784                                 until the 10s interval ends. With
785                                 these two options this rate limiting
786                                 may be modified. Use
787                                 <varname>StartLimitInterval=</varname>
788                                 to configure the checking interval
789                                 (defaults to 10s, set to 0 to disable
790                                 any kind of rate limiting). Use
791                                 <varname>StartLimitBurst=</varname> to
792                                 configure how many starts per interval
793                                 are allowed (defaults to 5). These
794                                 configuration options are particularly
795                                 useful in conjunction with
796                                 <varname>Restart=</varname>.</para></listitem>
797                         </varlistentry>
798
799                         <varlistentry>
800                                 <term><varname>StartLimitAction=</varname></term>
801
802                                 <listitem><para>Configure the action
803                                 to take if the rate limit configured
804                                 with
805                                 <varname>StartLimitInterval=</varname>
806                                 and
807                                 <varname>StartLimitBurst=</varname> is
808                                 hit. Takes one of
809                                 <option>none</option>,
810                                 <option>reboot</option>,
811                                 <option>reboot-force</option> or
812                                 <option>reboot-immediate</option>. If
813                                 <option>none</option> is set,
814                                 hitting the rate limit will trigger no
815                                 action besides that the start will not
816                                 be
817                                 permitted. <option>reboot</option>
818                                 causes a reboot following the normal
819                                 shutdown procedure (i.e. equivalent to
820                                 <command>systemctl reboot</command>),
821                                 <option>reboot-force</option> causes
822                                 an forced reboot which will terminate
823                                 all processes forcibly but should
824                                 cause no dirty file systems on reboot
825                                 (i.e. equivalent to <command>systemctl
826                                 reboot -f</command>) and
827                                 <option>reboot-immediate</option>
828                                 causes immediate execution of the
829                                 <citerefentry><refentrytitle>reboot</refentrytitle><manvolnum>2</manvolnum></citerefentry>
830                                 system call, which might result in
831                                 data loss.  Defaults to
832                                 <option>none</option>.</para></listitem>
833                         </varlistentry>
834
835                 </variablelist>
836         </refsect1>
837
838         <refsect1>
839                   <title>See Also</title>
840                   <para>
841                           <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
842                           <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
843                           <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
844                           <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>
845                   </para>
846         </refsect1>
847
848 </refentry>