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