man/systemd.service.xml

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   7   This file is part of systemd.
   8
   9   Copyright 2010 Lennart Poettering
  10
  11   systemd is free software; you can redistribute it and/or modify it
  12   under the terms of the GNU Lesser General Public License as published by
  13   the Free Software Foundation; either version 2.1 of the License, or
  14   (at your option) any later version.
  15
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  18   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  19   Lesser General Public License for more details.
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  21   You should have received a copy of the GNU Lesser General Public License
  22   along with systemd; If not, see <http://www.gnu.org/licenses/>.
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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>Service unit configuration</refpurpose>
  48         </refnamediv>
  49
  50         <refsynopsisdiv>
  51                 <para><filename><replaceable>service</replaceable>.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, and in
  76                 <citerefentry><refentrytitle>systemd.kill</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
  77                 which define the way the processes of the service are
  78                 terminated, and in
  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>
  82
  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
  96                 option.</para>
  97
  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.
 109                 </para>
 110         </refsect1>
 111
 112         <refsect1>
 113                 <title>Options</title>
 114
 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>
 122                 and
 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>
 126
 127                 <variablelist class='unit-directives'>
 128                         <varlistentry>
 129                                 <term><varname>Type=</varname></term>
 130
 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>
 139
 140                                 <para>If set to
 141                                 <option>simple</option> (the default
 142                                 if neither
 143                                 <varname>Type=</varname> nor
 144                                 <varname>BusName=</varname>, but
 145                                 <varname>ExecStart=</varname> are
 146                                 specified), it is expected that the
 147                                 process configured with
 148                                 <varname>ExecStart=</varname> is the
 149                                 main process of the service. In this
 150                                 mode, if the process offers
 151                                 functionality to other processes on
 152                                 the system, its communication channels
 153                                 should be installed before the daemon
 154                                 is started up (e.g. sockets set up by
 155                                 systemd, via socket activation), as
 156                                 systemd will immediately proceed
 157                                 starting follow-up units.</para>
 158
 159                                 <para>If set to
 160                                 <option>forking</option>, it is
 161                                 expected that the process configured
 162                                 with <varname>ExecStart=</varname>
 163                                 will call <function>fork()</function>
 164                                 as part of its start-up. The parent process is
 165                                 expected to exit when start-up is
 166                                 complete and all communication
 167                                 channels are set up. The child continues
 168                                 to run as the main daemon
 169                                 process. This is the behavior of
 170                                 traditional UNIX daemons. If this
 171                                 setting is used, it is recommended to
 172                                 also use the
 173                                 <varname>PIDFile=</varname> option, so
 174                                 that systemd can identify the main
 175                                 process of the daemon. systemd will
 176                                 proceed with starting follow-up units
 177                                 as soon as the parent process
 178                                 exits.</para>
 179
 180                                 <para>Behavior of
 181                                 <option>oneshot</option> is similar to
 182                                 <option>simple</option>; however, it
 183                                 is expected that the process has to
 184                                 exit before systemd starts follow-up
 185                                 units. <varname>RemainAfterExit=</varname>
 186                                 is particularly useful for this type
 187                                 of service. This is the implied
 188                                 default if neither
 189                                 <varname>Type=</varname> or
 190                                 <varname>ExecStart=</varname> are
 191                                 specified.</para>
 192
 193                                 <para>Behavior of
 194                                 <option>dbus</option> is similar to
 195                                 <option>simple</option>; however, it is
 196                                 expected that the daemon acquires a
 197                                 name on the D-Bus bus, as configured
 198                                 by
 199                                 <varname>BusName=</varname>. systemd
 200                                 will proceed with starting follow-up
 201                                 units after the D-Bus bus name has been
 202                                 acquired. Service units with this
 203                                 option configured implicitly gain
 204                                 dependencies on the
 205                                 <filename>dbus.socket</filename>
 206                                 unit. This type is the default if
 207                                 <varname>BusName=</varname> is
 208                                 specified.</para>
 209
 210                                 <para>Behavior of
 211                                 <option>notify</option> is similar to
 212                                 <option>simple</option>; however, it is
 213                                 expected that the daemon sends a
 214                                 notification message via
 215                                 <citerefentry><refentrytitle>sd_notify</refentrytitle><manvolnum>3</manvolnum></citerefentry>
 216                                 or an equivalent call when it has finished
 217                                 starting up. systemd will proceed with
 218                                 starting follow-up units after this
 219                                 notification message has been sent. If
 220                                 this option is used,
 221                                 <varname>NotifyAccess=</varname> (see
 222                                 below) should be set to open access to
 223                                 the notification socket provided by
 224                                 systemd. If
 225                                 <varname>NotifyAccess=</varname> is
 226                                 not set, it will be implicitly set to
 227                                 <option>main</option>. Note that
 228                                 currently
 229                                 <varname>Type=</varname><option>notify</option>
 230                                 will not work if used in combination with
 231                                 <varname>PrivateNetwork=</varname><option>yes</option>.</para>
 232
 233                                 <para>Behavior of
 234                                 <option>idle</option> is very similar
 235                                 to <option>simple</option>; however,
 236                                 actual execution of the service
 237                                 binary is delayed until all jobs are
 238                                 dispatched. This may be used to avoid
 239                                 interleaving of output of shell
 240                                 services with the status output on the
 241                                 console.</para>
 242                                 </listitem>
 243                         </varlistentry>
 244
 245                         <varlistentry>
 246                                 <term><varname>RemainAfterExit=</varname></term>
 247
 248                                 <listitem><para>Takes a boolean value
 249                                 that specifies whether the service
 250                                 shall be considered active even when
 251                                 all its processes exited. Defaults to
 252                                 <option>no</option>.</para>
 253                                 </listitem>
 254                         </varlistentry>
 255
 256                         <varlistentry>
 257                                 <term><varname>GuessMainPID=</varname></term>
 258
 259                                 <listitem><para>Takes a boolean value
 260                                 that specifies whether systemd should
 261                                 try to guess the main PID of a service
 262                                 if it cannot be determined
 263                                 reliably. This option is ignored
 264                                 unless <option>Type=forking</option>
 265                                 is set and <option>PIDFile=</option>
 266                                 is unset because for the other types
 267                                 or with an explicitly configured PID
 268                                 file, the main PID is always known. The
 269                                 guessing algorithm might come to
 270                                 incorrect conclusions if a daemon
 271                                 consists of more than one process. If
 272                                 the main PID cannot be determined,
 273                                 failure detection and automatic
 274                                 restarting of a service will not work
 275                                 reliably. Defaults to
 276                                 <option>yes</option>.</para>
 277                                 </listitem>
 278                         </varlistentry>
 279
 280                         <varlistentry>
 281                                 <term><varname>PIDFile=</varname></term>
 282
 283                                 <listitem><para>Takes an absolute file
 284                                 name pointing to the PID file of this
 285                                 daemon. Use of this option is
 286                                 recommended for services where
 287                                 <varname>Type=</varname> is set to
 288                                 <option>forking</option>. systemd will
 289                                 read the PID of the main process of
 290                                 the daemon after start-up of the
 291                                 service. systemd will not write to the
 292                                 file configured here.</para>
 293                                 </listitem>
 294                         </varlistentry>
 295
 296                         <varlistentry>
 297                                 <term><varname>BusName=</varname></term>
 298
 299                                 <listitem><para>Takes a D-Bus bus
 300                                 name that this service is reachable
 301                                 as. This option is mandatory for
 302                                 services where
 303                                 <varname>Type=</varname> is set to
 304                                 <option>dbus</option>, but its use
 305                                 is otherwise recommended if the process
 306                                 takes a name on the D-Bus bus.</para>
 307                                 </listitem>
 308                         </varlistentry>
 309
 310                         <varlistentry>
 311                                 <term><varname>BusPolicy=</varname></term>
 312
 313                                 <listitem><para>If specified, a custom
 314                                 <ulink url="https://code.google.com/p/d-bus/">kdbus</ulink>
 315                                 endpoint will be created and installed as the
 316                                 default bus node for the service. Such a custom
 317                                 endpoint can hold an own set of policy rules
 318                                 that are enforced on top of the bus-wide ones.
 319                                 The custom endpoint is named after the service
 320                                 it was created for, and its node will be
 321                                 bind-mounted over the default bus node
 322                                 location, so the service can only access the
 323                                 bus through its own endpoint. Note that custom
 324                                 bus endpoints default to a 'deny all' policy.
 325                                 Hence, if at least one
 326                                 <varname>BusPolicy=</varname> directive is
 327                                 given, you have to make sure to add explicit
 328                                 rules for everything the service should be able
 329                                 to do.</para>
 330                                 <para>The value of this directive is comprised
 331                                 of two parts; the bus name, and a verb to
 332                                 specify to granted access, which is one of
 333                                 <option>see</option>,
 334                                 <option>talk</option>, or
 335                                 <option>own</option>.
 336                                 <option>talk</option> implies
 337                                 <option>see</option>, and <option>own</option>
 338                                 implies both <option>talk</option> and
 339                                 <option>see</option>.
 340                                 If multiple access levels are specified for the
 341                                 same bus name, the most powerful one takes
 342                                 effect.
 343                                 </para>
 344                                 <para>Examples:</para>
 345                                 <programlisting>BusPolicy=org.freedesktop.systemd1 talk</programlisting>
 346                                 <programlisting>BusPolicy=org.foo.bar see</programlisting>
 347                                 <para>This option is only available on kdbus enabled systems.</para>
 348                                 </listitem>
 349                         </varlistentry>
 350
 351                         <varlistentry>
 352                                 <term><varname>ExecStart=</varname></term>
 353                                 <listitem><para>Commands with their
 354                                 arguments that are executed when this
 355                                 service is started. For each of the
 356                                 specified commands, the first argument
 357                                 must be an absolute and literal path
 358                                 to an executable.</para>
 359
 360                                 <para>When <varname>Type</varname> is
 361                                 not <option>oneshot</option>, only one
 362                                 command may and must be given. When
 363                                 <varname>Type=oneshot</varname> is
 364                                 used, none or more than one command
 365                                 may be specified. Multiple command
 366                                 lines may be concatenated in a single
 367                                 directive by separating them with
 368                                 semicolons (these semicolons must be
 369                                 passed as separate
 370                                 words). Alternatively, this directive
 371                                 may be specified more than once with
 372                                 the same effect.  Lone semicolons may
 373                                 be escaped as
 374                                 <literal>\;</literal>. If the empty
 375                                 string is assigned to this option, the
 376                                 list of commands to start is reset,
 377                                 prior assignments of this option will
 378                                 have no effect. If no
 379                                 <varname>ExecStart=</varname> is
 380                                 specified, then the service must have
 381                                 <varname>RemainAfterExit=yes</varname>
 382                                 set.</para>
 383
 384                                 <para>Each command line is split on
 385                                 whitespace, with the first item being
 386                                 the command to execute, and the
 387                                 subsequent items being the arguments.
 388                                 Double quotes ("...") and single
 389                                 quotes ('...') may be used, in which
 390                                 case everything until the next
 391                                 matching quote becomes part of the
 392                                 same argument. Quotes themselves are
 393                                 removed after parsing. In addition, a
 394                                 trailing backslash
 395                                 (<literal>\</literal>) may be used to
 396                                 merge lines. This syntax is intended
 397                                 to be very similar to shell syntax,
 398                                 but only the meta-characters and
 399                                 expansions described in the following
 400                                 paragraphs are understood.
 401                                 Specifically, redirection using
 402                                 <literal>&lt;</literal>,
 403                                 <literal>&lt;&lt;</literal>,
 404                                 <literal>&gt;</literal>, and
 405                                 <literal>&gt;&gt;</literal>, pipes
 406                                 using <literal>|</literal>, and
 407                                 running programs in the background
 408                                 using <literal>&amp;</literal>
 409                                 and <emphasis>other elements of shell
 410                                 syntax are not supported</emphasis>.
 411                                 </para>
 412
 413                                 <para>If more than one command is
 414                                 specified, the commands are invoked
 415                                 sequentially in the order they appear
 416                                 in the unit file. If one of the
 417                                 commands fails (and is not prefixed
 418                                 with <literal>-</literal>), other lines
 419                                 are not executed, and the unit is
 420                                 considered failed.</para>
 421
 422                                 <para>Unless
 423                                 <varname>Type=forking</varname> is
 424                                 set, the process started via this
 425                                 command line will be considered the
 426                                 main process of the daemon.</para>
 427
 428                                 <para>The command line accepts
 429                                 <literal>%</literal> specifiers as
 430                                 described in
 431                                 <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>.
 432                                 Note that the first argument of the
 433                                 command line (i.e. the program to
 434                                 execute) may not include
 435                                 specifiers.</para>
 436
 437                                 <para>Basic environment variable
 438                                 substitution is supported. Use
 439                                 <literal>${FOO}</literal> as part of a
 440                                 word, or as a word of its own, on the
 441                                 command line, in which case it will be
 442                                 replaced by the value of the
 443                                 environment variable including all
 444                                 whitespace it contains, resulting in a
 445                                 single argument. Use
 446                                 <literal>$FOO</literal> as a separate
 447                                 word on the command line, in which
 448                                 case it will be replaced by the value
 449                                 of the environment variable split at
 450                                 whitespace, resulting in zero or more
 451                                 arguments. To pass a literal dollar
 452                                 sign, use <literal>$$</literal>.
 453                                 Variables whose value is not known at
 454                                 expansion time are treated as empty
 455                                 strings. Note that the first argument
 456                                 (i.e. the program to execute) may not
 457                                 be a variable.</para>
 458
 459                                 <para>Variables to be used in this
 460                                 fashion may be defined through
 461                                 <varname>Environment=</varname> and
 462                                 <varname>EnvironmentFile=</varname>.
 463                                 In addition, variables listed in the
 464                                 section "Environment variables in
 465                                 spawned processes" in
 466                                 <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
 467                                 which are considered "static
 468                                 configuration", may be used (this includes
 469                                 e.g. <varname>$USER</varname>, but not
 470                                 <varname>$TERM</varname>).</para>
 471
 472                                 <para>Optionally, if the absolute file
 473                                 name is prefixed with
 474                                 <literal>@</literal>, the second token
 475                                 will be passed as
 476                                 <literal>argv[0]</literal> to the
 477                                 executed process, followed by the
 478                                 further arguments specified. If the
 479                                 absolute filename is prefixed with
 480                                 <literal>-</literal>, an exit code of
 481                                 the command normally considered a
 482                                 failure (i.e. non-zero exit status or
 483                                 abnormal exit due to signal) is ignored
 484                                 and considered success. If both
 485                                 <literal>-</literal> and
 486                                 <literal>@</literal> are used, they
 487                                 can appear in either order.</para>
 488
 489                                 <para>Note that this setting does not
 490                                 directly support shell command
 491                                 lines. If shell command lines are to
 492                                 be used, they need to be passed
 493                                 explicitly to a shell implementation
 494                                 of some kind. Example:</para>
 495                                 <programlisting>ExecStart=/bin/sh -c 'dmesg | tac'</programlisting>
 496                                 <para>Example:</para>
 497                                 <programlisting>ExecStart=/bin/echo one ; /bin/echo "two two"</programlisting>
 498                                 <para>This will execute
 499                                 <command>/bin/echo</command> two
 500                                 times, each time with one argument:
 501                                 <literal>one</literal> and
 502                                 <literal>two two</literal>,
 503                                 respectively. Because two commands are
 504                                 specified,
 505                                 <varname>Type=oneshot</varname> must
 506                                 be used.</para>
 507
 508                                 <para>Example:</para>
 509                                 <programlisting>ExecStart=/bin/echo / &gt;/dev/null &amp; \; \
 510 /bin/ls</programlisting>
 511                                 <para>This will execute
 512                                 <command>/bin/echo</command> with five
 513                                 arguments: <literal>/</literal>,
 514                                 <literal>&gt;/dev/null</literal>,
 515                                 <literal>&amp;</literal>,
 516                                 <literal>;</literal>, and
 517                                 <literal>/bin/ls</literal>.</para>
 518
 519                                 <para>Example:</para>
 520                                 <programlisting>Environment="ONE=one" 'TWO=two two'
 521 ExecStart=/bin/echo $ONE $TWO ${TWO}</programlisting>
 522                                 <para>This will execute
 523                                 <command>/bin/echo</command> with four
 524                                 arguments: <literal>one</literal>,
 525                                 <literal>two</literal>,
 526                                 <literal>two</literal>, and
 527                                 <literal>two two</literal>.</para>
 528                               </listitem>
 529                         </varlistentry>
 530
 531                         <varlistentry>
 532                                 <term><varname>ExecStartPre=</varname></term>
 533                                 <term><varname>ExecStartPost=</varname></term>
 534                                 <listitem><para>Additional commands
 535                                 that are executed before or after
 536                                 the command in
 537                                 <varname>ExecStart=</varname>, respectively.
 538                                 Syntax is the same as for
 539                                 <varname>ExecStart=</varname>, except
 540                                 that multiple command lines are allowed
 541                                 and the commands are executed one
 542                                 after the other, serially.</para>
 543
 544                                 <para>If any of those commands (not
 545                                 prefixed with <literal>-</literal>)
 546                                 fail, the rest are not executed and
 547                                 the unit is considered failed.</para>
 548                                 </listitem>
 549                         </varlistentry>
 550
 551                         <varlistentry>
 552                                 <term><varname>ExecReload=</varname></term>
 553                                 <listitem><para>Commands to execute to
 554                                 trigger a configuration reload in the
 555                                 service. This argument takes multiple
 556                                 command lines, following the same
 557                                 scheme as described for
 558                                 <varname>ExecStart=</varname>
 559                                 above. Use of this setting is
 560                                 optional. Specifier and environment
 561                                 variable substitution is supported
 562                                 here following the same scheme as for
 563                                 <varname>ExecStart=</varname>.</para>
 564
 565                                 <para>One additional, special
 566                                 environment variable is set: if known,
 567                                 <varname>$MAINPID</varname> is set to
 568                                 the main process of the daemon, and
 569                                 may be used for command lines like the
 570                                 following:</para>
 571
 572                                 <programlisting>/bin/kill -HUP $MAINPID</programlisting>
 573
 574                                 <para>Note however that reloading a
 575                                 daemon by sending a signal (as with
 576                                 the example line above) is usually not
 577                                 a good choice, because this is an
 578                                 asynchronous operation and hence not
 579                                 suitable to order reloads of multiple
 580                                 services against each other. It is
 581                                 strongly recommended to set
 582                                 <varname>ExecReload=</varname> to a
 583                                 command that not only triggers a
 584                                 configuration reload of the daemon,
 585                                 but also synchronously waits for it to
 586                                 complete.</para>
 587                                 </listitem>
 588                         </varlistentry>
 589
 590                         <varlistentry>
 591                                 <term><varname>ExecStop=</varname></term>
 592                                 <listitem><para>Commands to execute to
 593                                 stop the service started via
 594                                 <varname>ExecStart=</varname>. This
 595                                 argument takes multiple command lines,
 596                                 following the same scheme as described
 597                                 for <varname>ExecStart=</varname>
 598                                 above. Use of this setting is
 599                                 optional. After the commands configured
 600                                 in this option are run, all processes
 601                                 remaining for a service are
 602                                 terminated according to the
 603                                 <varname>KillMode=</varname> setting
 604                                 (see
 605                                 <citerefentry><refentrytitle>systemd.kill</refentrytitle><manvolnum>5</manvolnum></citerefentry>). If
 606                                 this option is not specified, the
 607                                 process is terminated immediately when
 608                                 service stop is requested. Specifier
 609                                 and environment variable substitution
 610                                 is supported (including
 611                                 <varname>$MAINPID</varname>, see
 612                                 above).</para></listitem>
 613                         </varlistentry>
 614
 615                         <varlistentry>
 616                                 <term><varname>ExecStopPost=</varname></term>
 617                                 <listitem><para>Additional commands
 618                                 that are executed after the service
 619                                 was stopped. This includes cases where
 620                                 the commands configured in
 621                                 <varname>ExecStop=</varname> were used,
 622                                 where the service does not have any
 623                                 <varname>ExecStop=</varname> defined, or
 624                                 where the service exited unexpectedly. This
 625                                 argument takes multiple command lines,
 626                                 following the same scheme as described
 627                                 for <varname>ExecStart</varname>. Use
 628                                 of these settings is
 629                                 optional. Specifier and environment
 630                                 variable substitution is
 631                                 supported.</para></listitem>
 632                         </varlistentry>
 633
 634                         <varlistentry>
 635                                 <term><varname>RestartSec=</varname></term>
 636                                 <listitem><para>Configures the time to
 637                                 sleep before restarting a service (as
 638                                 configured with
 639                                 <varname>Restart=</varname>). Takes a
 640                                 unit-less value in seconds, or a time
 641                                 span value such as "5min
 642                                 20s". Defaults to
 643                                 100ms.</para></listitem>
 644                         </varlistentry>
 645
 646                         <varlistentry>
 647                                 <term><varname>TimeoutStartSec=</varname></term>
 648                                 <listitem><para>Configures the time to
 649                                 wait for start-up. If a
 650                                 daemon service does not signal
 651                                 start-up completion within the
 652                                 configured time, the service will be
 653                                 considered failed and will be shut
 654                                 down again.
 655                                 Takes a unit-less value in seconds, or a
 656                                 time span value such as "5min
 657                                 20s". Pass <literal>0</literal> to
 658                                 disable the timeout logic. Defaults to
 659                                 <varname>DefaultTimeoutStartSec=</varname> from
 660                                 the manager configuration file, except
 661                                 when <varname>Type=oneshot</varname> is
 662                                 used, in which case the timeout
 663                                 is disabled by default
 664                                 (see <citerefentry><refentrytitle>systemd-systemd.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>).
 665                                 </para></listitem>
 666                         </varlistentry>
 667
 668                         <varlistentry>
 669                                 <term><varname>TimeoutStopSec=</varname></term>
 670                                 <listitem><para>Configures the time to
 671                                 wait for stop. If a service is asked
 672                                 to stop, but does not terminate in the
 673                                 specified time, it will be terminated
 674                                 forcibly via <constant>SIGTERM</constant>,
 675                                 and after another timeout of equal duration
 676                                 with <constant>SIGKILL</constant> (see
 677                                 <varname>KillMode=</varname>
 678                                 in <citerefentry><refentrytitle>systemd.kill</refentrytitle><manvolnum>5</manvolnum></citerefentry>).
 679                                 Takes a unit-less value in seconds, or a
 680                                 time span value such as "5min
 681                                 20s". Pass <literal>0</literal> to disable
 682                                 the timeout logic. Defaults to
 683                                 <varname>DefaultTimeoutStopSec=</varname> from the
 684                                 manager configuration file
 685                                 (see <citerefentry><refentrytitle>systemd-systemd.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>).
 686                                 </para></listitem>
 687                         </varlistentry>
 688
 689                         <varlistentry>
 690                                 <term><varname>TimeoutSec=</varname></term>
 691                                 <listitem><para>A shorthand for configuring
 692                                 both <varname>TimeoutStartSec=</varname>
 693                                 and <varname>TimeoutStopSec=</varname>
 694                                 to the specified value.
 695                                 </para></listitem>
 696                         </varlistentry>
 697
 698                         <varlistentry>
 699                                 <term><varname>WatchdogSec=</varname></term>
 700                                 <listitem><para>Configures the
 701                                 watchdog timeout for a service. The
 702                                 watchdog is activated when the start-up is
 703                                 completed. The service must call
 704                                 <citerefentry><refentrytitle>sd_notify</refentrytitle><manvolnum>3</manvolnum></citerefentry>
 705                                 regularly with <literal>WATCHDOG=1</literal>
 706                                 (i.e. the "keep-alive ping"). If the time
 707                                 between two such calls is larger than
 708                                 the configured time, then the service
 709                                 is placed in a failed state. By
 710                                 setting <varname>Restart=</varname> to
 711                                 <option>on-failure</option> or
 712                                 <option>always</option>, the service
 713                                 will be automatically restarted. The
 714                                 time configured here will be passed to
 715                                 the executed service process in the
 716                                 <varname>WATCHDOG_USEC=</varname>
 717                                 environment variable. This allows
 718                                 daemons to automatically enable the
 719                                 keep-alive pinging logic if watchdog
 720                                 support is enabled for the service. If
 721                                 this option is used,
 722                                 <varname>NotifyAccess=</varname> (see
 723                                 below) should be set to open access to
 724                                 the notification socket provided by
 725                                 systemd. If
 726                                 <varname>NotifyAccess=</varname> is
 727                                 not set, it will be implicitly set to
 728                                 <option>main</option>. Defaults to 0,
 729                                 which disables this
 730                                 feature.</para></listitem>
 731                         </varlistentry>
 732
 733                         <varlistentry>
 734                                 <term><varname>Restart=</varname></term>
 735                                 <listitem><para>Configures whether the
 736                                 service shall be restarted when the
 737                                 service process exits, is killed,
 738                                 or a timeout is reached. The service
 739                                 process may be the main service
 740                                 process, but it may also be one of the
 741                                 processes specified with
 742                                 <varname>ExecStartPre=</varname>,
 743                                 <varname>ExecStartPost=</varname>,
 744                                 <varname>ExecStop=</varname>,
 745                                 <varname>ExecStopPost=</varname>, or
 746                                 <varname>ExecReload=</varname>.
 747                                 When the death of the process is a
 748                                 result of systemd operation (e.g. service
 749                                 stop or restart), the service will not be
 750                                 restarted. Timeouts include missing
 751                                 the watchdog "keep-alive ping"
 752                                 deadline and a service start, reload,
 753                                 and stop operation timeouts.</para>
 754
 755                                 <para>Takes one of
 756                                 <option>no</option>,
 757                                 <option>on-success</option>,
 758                                 <option>on-failure</option>,
 759                                 <option>on-abnormal</option>,
 760                                 <option>on-watchdog</option>,
 761                                 <option>on-abort</option>, or
 762                                 <option>always</option>. If set to
 763                                 <option>no</option> (the default), the
 764                                 service will not be restarted. If set
 765                                 to <option>on-success</option>, it
 766                                 will be restarted only when the
 767                                 service process exits cleanly.  In
 768                                 this context, a clean exit means an
 769                                 exit code of 0, or one of the signals
 770                                 <constant>SIGHUP</constant>,
 771                                 <constant>SIGINT</constant>,
 772                                 <constant>SIGTERM</constant> or
 773                                 <constant>SIGPIPE</constant>, and
 774                                 additionally, exit statuses and
 775                                 signals specified in
 776                                 <varname>SuccessExitStatus=</varname>.
 777                                 If set to <option>on-failure</option>,
 778                                 the service will be restarted when the
 779                                 process exits with a non-zero exit
 780                                 code, is terminated by a signal
 781                                 (including on core dump, but excluding
 782                                 the aforementiond four signals), when
 783                                 an operation (such as service reload)
 784                                 times out, and when the configured
 785                                 watchdog timeout is triggered.  If set
 786                                 to <option>on-abnormal</option>, the
 787                                 service will be restarted when the
 788                                 process is terminated by a signal
 789                                 (including on core dump, excluding the
 790                                 aforementioned four signals), when an
 791                                 operation times out, or when the
 792                                 watchdog timeout is triggered. If set
 793                                 to <option>on-abort</option>, the
 794                                 service will be restarted only if the
 795                                 service process exits due to an
 796                                 uncaught signal not specified as a
 797                                 clean exit status.  If set to
 798                                 <option>on-watchdog</option>, the
 799                                 service will be restarted only if the
 800                                 watchdog timeout for the service
 801                                 expires.  If set to
 802                                 <option>always</option>, the service
 803                                 will be restarted regardless of
 804                                 whether it exited cleanly or not, got
 805                                 terminated abnormally by a signal, or
 806                                 hit a timeout.</para>
 807
 808                                 <table>
 809                                         <title>Exit causes and the effect of the <varname>Restart=</varname> settings on them</title>
 810
 811                                         <tgroup cols='2'>
 812                                                 <colspec colname='path' />
 813                                                 <colspec colname='expl' />
 814                                                 <thead>
 815                                                         <row>
 816                                                                 <entry>Restart settings/Exit causes</entry>
 817                                                                 <entry><option>no</option></entry>
 818                                                                 <entry><option>always</option></entry>
 819                                                                 <entry><option>on-success</option></entry>
 820                                                                 <entry><option>on-failure</option></entry>
 821                                                                 <entry><option>on-abnormal</option></entry>
 822                                                                 <entry><option>on-abort</option></entry>
 823                                                                 <entry><option>on-watchdog</option></entry>
 824                                                         </row>
 825                                                 </thead>
 826                                                 <tbody>
 827                                                         <row>
 828                                                                 <entry>Clean exit code or signal</entry>
 829                                                                 <entry/>
 830                                                                 <entry>X</entry>
 831                                                                 <entry>X</entry>
 832                                                                 <entry/>
 833                                                                 <entry/>
 834                                                                 <entry/>
 835                                                                 <entry/>
 836                                                         </row>
 837                                                         <row>
 838                                                                 <entry>Unclean exit code</entry>
 839                                                                 <entry/>
 840                                                                 <entry>X</entry>
 841                                                                 <entry/>
 842                                                                 <entry>X</entry>
 843                                                                 <entry/>
 844                                                                 <entry/>
 845                                                                 <entry/>
 846                                                         </row>
 847                                                         <row>
 848                                                                 <entry>Unclean signal</entry>
 849                                                                 <entry/>
 850                                                                 <entry>X</entry>
 851                                                                 <entry/>
 852                                                                 <entry>X</entry>
 853                                                                 <entry>X</entry>
 854                                                                 <entry>X</entry>
 855                                                                 <entry/>
 856                                                         </row>
 857                                                         <row>
 858                                                                 <entry>Timeout</entry>
 859                                                                 <entry/>
 860                                                                 <entry>X</entry>
 861                                                                 <entry/>
 862                                                                 <entry>X</entry>
 863                                                                 <entry>X</entry>
 864                                                                 <entry/>
 865                                                                 <entry/>
 866                                                         </row>
 867                                                         <row>
 868                                                                 <entry>Watchdog</entry>
 869                                                                 <entry/>
 870                                                                 <entry>X</entry>
 871                                                                 <entry/>
 872                                                                 <entry>X</entry>
 873                                                                 <entry>X</entry>
 874                                                                 <entry/>
 875                                                                 <entry>X</entry>
 876                                                         </row>
 877                                                 </tbody>
 878                                         </tgroup>
 879                                 </table>
 880
 881                                 <para>As exceptions to the setting
 882                                 above the service will not be
 883                                 restarted if the exit code or signal
 884                                 is specified in
 885                                 <varname>RestartPreventExitStatus=</varname>
 886                                 (see below). Also, the services will
 887                                 always be restarted if the exit code
 888                                 or signal is specified in
 889                                 <varname>RestartForceExitStatus=</varname>
 890                                 (see below).</para>
 891
 892                                 <para>Setting this to
 893                                 <option>on-failure</option> is the
 894                                 recommended choice for long-running
 895                                 services, in order to increase
 896                                 reliability by attempting automatic
 897                                 recovery from errors. For services
 898                                 that shall be able to terminate on
 899                                 their own choice (and avoid
 900                                 immediate restarting),
 901                                 <option>on-abnormal</option> is an
 902                                 alternative choice.</para>
 903                                 </listitem>
 904                         </varlistentry>
 905
 906                         <varlistentry>
 907                                 <term><varname>SuccessExitStatus=</varname></term>
 908                                 <listitem><para>Takes a list of exit
 909                                 status definitions that when returned
 910                                 by the main service process will be
 911                                 considered successful termination, in
 912                                 addition to the normal successful exit
 913                                 code 0 and the signals <constant>SIGHUP</constant>, <constant>SIGINT</constant>,
 914                                 <constant>SIGTERM</constant>, and <constant>SIGPIPE</constant>. Exit status
 915                                 definitions can either be numeric exit
 916                                 codes or termination signal names,
 917                                 separated by spaces. For example:
 918                                 <programlisting>SuccessExitStatus=1 2 8 SIGKILL</programlisting>
 919                                 ensures that exit codes 1, 2, 8 and
 920                                 the termination signal
 921                                 <constant>SIGKILL</constant> are
 922                                 considered clean service terminations.
 923                                 </para>
 924
 925                                 <para>Note that if a process has a
 926                                 signal handler installed and exits by
 927                                 calling
 928                                 <citerefentry><refentrytitle>_exit</refentrytitle><manvolnum>2</manvolnum></citerefentry>
 929                                 in response to a signal, the
 930                                 information about the signal is lost.
 931                                 Programs should instead perform cleanup and kill themselves with the same signal instead. See
 932                                 <ulink url="http://www.cons.org/cracauer/sigint.html">Proper handling of SIGINT/SIGQUIT — How to be a proper program</ulink>.</para>
 933
 934                                 <para>This option may appear more than once,
 935                                 in which case the list of successful
 936                                 exit statuses is merged. If the empty
 937                                 string is assigned to this option, the
 938                                 list is reset, all prior assignments
 939                                 of this option will have no
 940                                 effect.</para></listitem>
 941                         </varlistentry>
 942
 943                         <varlistentry>
 944                                 <term><varname>RestartPreventExitStatus=</varname></term>
 945                                 <listitem><para>Takes a list of exit
 946                                 status definitions that when returned
 947                                 by the main service process will
 948                                 prevent automatic service restarts,
 949                                 regardless of the restart setting
 950                                 configured with
 951                                 <varname>Restart=</varname>. Exit
 952                                 status definitions can either be
 953                                 numeric exit codes or termination
 954                                 signal names, and are separated by
 955                                 spaces. Defaults to the empty list, so
 956                                 that, by default, no exit status is
 957                                 excluded from the configured restart
 958                                 logic. For example:
 959                                 <programlisting>RestartPreventExitStatus=1 6 SIGABRT</programlisting> ensures that exit
 960                                 codes 1 and 6 and the termination
 961                                 signal <constant>SIGABRT</constant> will
 962                                 not result in automatic service
 963                                 restarting. This
 964                                 option may appear more than once, in
 965                                 which case the list of restart-preventing
 966                                 statuses is merged. If the empty
 967                                 string is assigned to this option, the
 968                                 list is reset and all prior assignments
 969                                 of this option will have no
 970                                 effect.</para></listitem>
 971                         </varlistentry>
 972
 973                         <varlistentry>
 974                                 <term><varname>RestartForceExitStatus=</varname></term>
 975                                 <listitem><para>Takes a list of exit
 976                                 status definitions that when returned
 977                                 by the main service process will force
 978                                 automatic service restarts, regardless
 979                                 of the restart setting configured with
 980                                 <varname>Restart=</varname>. The
 981                                 argument format is similar to
 982                                 <varname>RestartPreventExitStatus=</varname>.</para></listitem>
 983                         </varlistentry>
 984
 985                         <varlistentry>
 986                                 <term><varname>PermissionsStartOnly=</varname></term>
 987                                 <listitem><para>Takes a boolean
 988                                 argument. If true, the permission-related
 989                                 execution options, as
 990                                 configured with
 991                                 <varname>User=</varname> and similar
 992                                 options (see
 993                                 <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 994                                 for more information), are only applied
 995                                 to the process started with
 996                                 <varname>ExecStart=</varname>, and not
 997                                 to the various other
 998                                 <varname>ExecStartPre=</varname>,
 999                                 <varname>ExecStartPost=</varname>,
1000                                 <varname>ExecReload=</varname>,
1001                                 <varname>ExecStop=</varname>, and
1002                                 <varname>ExecStopPost=</varname>
1003                                 commands. If false, the setting is
1004                                 applied to all configured commands the
1005                                 same way. Defaults to
1006                                 false.</para></listitem>
1007                         </varlistentry>
1008
1009                         <varlistentry>
1010                                 <term><varname>RootDirectoryStartOnly=</varname></term>
1011                                 <listitem><para>Takes a boolean
1012                                 argument. If true, the root directory,
1013                                 as configured with the
1014                                 <varname>RootDirectory=</varname>
1015                                 option (see
1016                                 <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>
1017                                 for more information), is only applied
1018                                 to the process started with
1019                                 <varname>ExecStart=</varname>, and not
1020                                 to the various other
1021                                 <varname>ExecStartPre=</varname>,
1022                                 <varname>ExecStartPost=</varname>,
1023                                 <varname>ExecReload=</varname>,
1024                                 <varname>ExecStop=</varname>, and
1025                                 <varname>ExecStopPost=</varname>
1026                                 commands. If false, the setting is
1027                                 applied to all configured commands the
1028                                 same way. Defaults to
1029                                 false.</para></listitem>
1030                         </varlistentry>
1031
1032                         <varlistentry>
1033                                 <term><varname>NonBlocking=</varname></term>
1034                                 <listitem><para>Set the
1035                                 <constant>O_NONBLOCK</constant> flag
1036                                 for all file descriptors passed via
1037                                 socket-based activation. If true, all
1038                                 file descriptors >= 3 (i.e. all except
1039                                 stdin, stdout, and stderr) will have
1040                                 the <constant>O_NONBLOCK</constant> flag
1041                                 set and hence are in
1042                                 non-blocking mode. This option is only
1043                                 useful in conjunction with a socket
1044                                 unit, as described in
1045                                 <citerefentry><refentrytitle>systemd.socket</refentrytitle><manvolnum>5</manvolnum></citerefentry>. Defaults
1046                                 to false.</para></listitem>
1047                         </varlistentry>
1048
1049                         <varlistentry>
1050                                 <term><varname>NotifyAccess=</varname></term>
1051                                 <listitem><para>Controls access to the
1052                                 service status notification socket, as
1053                                 accessible via the
1054                                 <citerefentry><refentrytitle>sd_notify</refentrytitle><manvolnum>3</manvolnum></citerefentry>
1055                                 call. Takes one of
1056                                 <option>none</option> (the default),
1057                                 <option>main</option> or
1058                                 <option>all</option>. If
1059                                 <option>none</option>, no daemon status
1060                                 updates are accepted from the service
1061                                 processes, all status update messages
1062                                 are ignored. If <option>main</option>,
1063                                 only service updates sent from the
1064                                 main process of the service are
1065                                 accepted. If <option>all</option>, all
1066                                 services updates from all members of
1067                                 the service's control group are
1068                                 accepted. This option should be set to
1069                                 open access to the notification socket
1070                                 when using
1071                                 <varname>Type=notify</varname> or
1072                                 <varname>WatchdogSec=</varname> (see
1073                                 above). If those options are used but
1074                                 <varname>NotifyAccess=</varname> is not
1075                                 configured, it will be implicitly set
1076                                 to
1077                                 <option>main</option>.</para></listitem>
1078                         </varlistentry>
1079
1080                         <varlistentry>
1081                                 <term><varname>Sockets=</varname></term>
1082                                 <listitem><para>Specifies the name of
1083                                 the socket units this service shall
1084                                 inherit the sockets from when the
1085                                 service is started. Normally it
1086                                 should not be necessary to use this
1087                                 setting as all sockets whose unit
1088                                 shares the same name as the service
1089                                 (ignoring the different suffix of course)
1090                                 are passed to the spawned
1091                                 process.</para>
1092
1093                                 <para>Note that the same socket may be
1094                                 passed to multiple processes at the
1095                                 same time. Also note that a different
1096                                 service may be activated on incoming
1097                                 traffic than that which inherits the
1098                                 sockets. Or in other words: the
1099                                 <varname>Service=</varname> setting of
1100                                 <filename>.socket</filename> units
1101                                 does not have to match the inverse of
1102                                 the <varname>Sockets=</varname>
1103                                 setting of the
1104                                 <filename>.service</filename> it
1105                                 refers to.</para>
1106
1107                                 <para>This option may appear more than
1108                                 once, in which case the list of socket
1109                                 units is merged. If the empty string
1110                                 is assigned to this option, the list of
1111                                 sockets is reset, and all prior uses of
1112                                 this setting will have no
1113                                 effect.</para></listitem>
1114                         </varlistentry>
1115
1116                         <varlistentry>
1117                                 <term><varname>StartLimitInterval=</varname></term>
1118                                 <term><varname>StartLimitBurst=</varname></term>
1119
1120                                 <listitem><para>Configure service
1121                                 start rate limiting. By default,
1122                                 services which are started more
1123                                 than 5 times within 10 seconds are not
1124                                 permitted to start any more times
1125                                 until the 10 second interval ends. With
1126                                 these two options, this rate limiting
1127                                 may be modified. Use
1128                                 <varname>StartLimitInterval=</varname>
1129                                 to configure the checking interval (defaults to
1130                                 <varname>DefaultStartLimitInterval=</varname> in
1131                                 manager configuration file, set to 0 to disable
1132                                 any kind of rate limiting). Use
1133                                 <varname>StartLimitBurst=</varname> to
1134                                 configure how many starts per interval
1135                                 are allowed (defaults to
1136                                 <varname>DefaultStartLimitBurst=</varname> in
1137                                 manager configuration file). These
1138                                 configuration options are particularly
1139                                 useful in conjunction with
1140                                 <varname>Restart=</varname>; however,
1141                                 they apply to all kinds of starts
1142                                 (including manual), not just those
1143                                 triggered by the
1144                                 <varname>Restart=</varname> logic.
1145                                 Note that units which are configured
1146                                 for <varname>Restart=</varname> and
1147                                 which reach the start limit are not
1148                                 attempted to be restarted anymore;
1149                                 however, they may still be restarted
1150                                 manually at a later point, from which
1151                                 point on, the restart logic is again
1152                                 activated. Note that
1153                                 <command>systemctl
1154                                 reset-failed</command> will cause the
1155                                 restart rate counter for a service to
1156                                 be flushed, which is useful if the
1157                                 administrator wants to manually start
1158                                 a service and the start limit
1159                                 interferes with
1160                                 that.</para></listitem>
1161                         </varlistentry>
1162
1163                         <varlistentry>
1164                                 <term><varname>StartLimitAction=</varname></term>
1165
1166                                 <listitem><para>Configure the action
1167                                 to take if the rate limit configured
1168                                 with
1169                                 <varname>StartLimitInterval=</varname>
1170                                 and
1171                                 <varname>StartLimitBurst=</varname> is
1172                                 hit. Takes one of
1173                                 <option>none</option>,
1174                                 <option>reboot</option>,
1175                                 <option>reboot-force</option>,
1176                                 <option>reboot-immediate</option>,
1177                                 <option>poweroff</option>,
1178                                 <option>poweroff-force</option> or
1179                                 <option>poweroff-immediate</option>. If
1180                                 <option>none</option> is set, hitting
1181                                 the rate limit will trigger no action
1182                                 besides that the start will not be
1183                                 permitted. <option>reboot</option>
1184                                 causes a reboot following the normal
1185                                 shutdown procedure (i.e. equivalent to
1186                                 <command>systemctl reboot</command>).
1187                                 <option>reboot-force</option> causes a
1188                                 forced reboot which will terminate all
1189                                 processes forcibly but should cause no
1190                                 dirty file systems on reboot
1191                                 (i.e. equivalent to <command>systemctl
1192                                 reboot -f</command>) and
1193                                 <option>reboot-immediate</option>
1194                                 causes immediate execution of the
1195                                 <citerefentry><refentrytitle>reboot</refentrytitle><manvolnum>2</manvolnum></citerefentry>
1196                                 system call, which might result in
1197                                 data loss. Similar,
1198                                 <option>poweroff</option>,
1199                                 <option>poweroff-force</option>,
1200                                 <option>poweroff-immediate</option>
1201                                 have the effect of powering down the
1202                                 system with similar
1203                                 semantics. Defaults to
1204                                 <option>none</option>.</para></listitem>
1205                         </varlistentry>
1206
1207                         <varlistentry>
1208                                 <term><varname>FailureAction=</varname></term>
1209                                 <listitem><para>Configure the action
1210                                 to take when the service enters a failed
1211                                 state. Takes the same values as
1212                                 <varname>StartLimitAction=</varname>
1213                                 and executes the same actions.
1214                                 Defaults to <option>none</option>.
1215                                 </para></listitem>
1216                         </varlistentry>
1217
1218                         <varlistentry>
1219                                 <term><varname>RebootArgument=</varname></term>
1220                                 <listitem><para>Configure the optional
1221                                 argument for the
1222                                 <citerefentry><refentrytitle>reboot</refentrytitle><manvolnum>2</manvolnum></citerefentry>
1223                                 system call if
1224                                 <varname>StartLimitAction=</varname>
1225                                 or <varname>FailureAction=</varname>
1226                                 is a reboot action. This works just
1227                                 like the optional argument to
1228                                 <command>systemctl reboot</command>
1229                                 command.</para></listitem>
1230                         </varlistentry>
1231
1232                 </variablelist>
1233
1234                 <para>Check
1235                 <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>
1236                 and
1237                 <citerefentry><refentrytitle>systemd.kill</refentrytitle><manvolnum>5</manvolnum></citerefentry>
1238                 for more settings.</para>
1239
1240         </refsect1>
1241
1242         <refsect1>
1243                 <title>Compatibility Options</title>
1244
1245                 <para>The following options are also available in the
1246                 <literal>[Service]</literal> section, but exist purely
1247                 for compatibility reasons and should not be used in
1248                 newly written service files.</para>
1249
1250                 <variablelist class='unit-directives'>
1251                         <varlistentry>
1252                                 <term><varname>SysVStartPriority=</varname></term>
1253                                 <listitem><para>Set the SysV start
1254                                 priority to use to order this service
1255                                 in relation to SysV services lacking
1256                                 LSB headers. This option is only
1257                                 necessary to fix ordering in relation
1258                                 to legacy SysV services that have no
1259                                 ordering information encoded in the
1260                                 script headers. As such, it should only
1261                                 be used as a temporary compatibility
1262                                 option and should not be used in new unit
1263                                 files. Almost always, it is a better
1264                                 choice to add explicit ordering
1265                                 directives via
1266                                 <varname>After=</varname> or
1267                                 <varname>Before=</varname>,
1268                                 instead. For more details, see
1269                                 <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>.
1270                                 If used, pass an integer value in the
1271                                 range 0-99.</para></listitem>
1272                         </varlistentry>
1273                 </variablelist>
1274         </refsect1>
1275
1276         <refsect1>
1277                   <title>See Also</title>
1278                   <para>
1279                           <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
1280                           <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
1281                           <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
1282                           <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
1283                           <citerefentry><refentrytitle>systemd.resource-control</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
1284                           <citerefentry><refentrytitle>systemd.kill</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
1285                           <citerefentry><refentrytitle>systemd.directives</refentrytitle><manvolnum>7</manvolnum></citerefentry>
1286                   </para>
1287         </refsect1>
1288
1289 </refentry>