man/systemd.exec.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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  19   Lesser General Public License for more details.
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  24
  25 <refentry id="systemd.exec">
  26         <refentryinfo>
  27                 <title>systemd.exec</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.exec</refentrytitle>
  42                 <manvolnum>5</manvolnum>
  43         </refmeta>
  44
  45         <refnamediv>
  46                 <refname>systemd.exec</refname>
  47                 <refpurpose>Execution environment configuration</refpurpose>
  48         </refnamediv>
  49
  50         <refsynopsisdiv>
  51                 <para><filename>systemd.service</filename>,
  52                 <filename>systemd.socket</filename>,
  53                 <filename>systemd.mount</filename>,
  54                 <filename>systemd.swap</filename></para>
  55         </refsynopsisdiv>
  56
  57         <refsect1>
  58                 <title>Description</title>
  59
  60                 <para>Unit configuration files for services, sockets,
  61                 mount points and swap devices share a subset of
  62                 configuration options which define the execution
  63                 environment of spawned processes.</para>
  64
  65                 <para>This man page lists the configuration options
  66                 shared by these four unit types. See
  67                 <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>
  68                 for the common options of all unit configuration
  69                 files, and
  70                 <citerefentry><refentrytitle>systemd.service</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
  71                 <citerefentry><refentrytitle>systemd.socket</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
  72                 <citerefentry><refentrytitle>systemd.swap</refentrytitle><manvolnum>5</manvolnum></citerefentry>
  73                 and
  74                 <citerefentry><refentrytitle>systemd.mount</refentrytitle><manvolnum>5</manvolnum></citerefentry>
  75                 for more information on the specific unit
  76                 configuration files. The execution specific
  77                 configuration options are configured in the [Service],
  78                 [Socket], [Mount], or [Swap] sections, depending on the unit
  79                 type.</para>
  80         </refsect1>
  81
  82         <refsect1>
  83                 <title>Options</title>
  84
  85                 <variablelist>
  86
  87                         <varlistentry>
  88                                 <term><varname>WorkingDirectory=</varname></term>
  89
  90                                 <listitem><para>Takes an absolute
  91                                 directory path. Sets the working
  92                                 directory for executed processes. If
  93                                 not set defaults to the root directory
  94                                 when systemd is running as a system
  95                                 instance and the respective user's
  96                                 home directory if run as
  97                                 user.</para></listitem>
  98                         </varlistentry>
  99
 100                         <varlistentry>
 101                                 <term><varname>RootDirectory=</varname></term>
 102
 103                                 <listitem><para>Takes an absolute
 104                                 directory path. Sets the root
 105                                 directory for executed processes, with
 106                                 the
 107                                 <citerefentry><refentrytitle>chroot</refentrytitle><manvolnum>2</manvolnum></citerefentry>
 108                                 system call. If this is used it must
 109                                 be ensured that the process and all
 110                                 its auxiliary files are available in
 111                                 the <function>chroot()</function>
 112                                 jail.</para></listitem>
 113                         </varlistentry>
 114
 115                         <varlistentry>
 116                                 <term><varname>User=</varname></term>
 117                                 <term><varname>Group=</varname></term>
 118
 119                                 <listitem><para>Sets the Unix user
 120                                 or group that the processes are executed
 121                                 as, respectively. Takes a single user or group
 122                                 name or ID as argument. If no group is
 123                                 set, the default group of the user is
 124                                 chosen.</para></listitem>
 125                         </varlistentry>
 126
 127                         <varlistentry>
 128                                 <term><varname>SupplementaryGroups=</varname></term>
 129
 130                                 <listitem><para>Sets the supplementary
 131                                 Unix groups the processes are executed
 132                                 as. This takes a space separated list
 133                                 of group names or IDs. This option may
 134                                 be specified more than once in which
 135                                 case all listed groups are set as
 136                                 supplementary groups. When the empty
 137                                 string is assigned the list of
 138                                 supplementary groups is reset, and all
 139                                 assignments prior to this one will
 140                                 have no effect. In any way, this
 141                                 option does not override, but extends
 142                                 the list of supplementary groups
 143                                 configured in the system group
 144                                 database for the
 145                                 user.</para></listitem>
 146                         </varlistentry>
 147
 148                         <varlistentry>
 149                                 <term><varname>Nice=</varname></term>
 150
 151                                 <listitem><para>Sets the default nice
 152                                 level (scheduling priority) for
 153                                 executed processes. Takes an integer
 154                                 between -20 (highest priority) and 19
 155                                 (lowest priority). See
 156                                 <citerefentry><refentrytitle>setpriority</refentrytitle><manvolnum>2</manvolnum></citerefentry>
 157                                 for details.</para></listitem>
 158                         </varlistentry>
 159
 160                         <varlistentry>
 161                                 <term><varname>OOMScoreAdjust=</varname></term>
 162
 163                                 <listitem><para>Sets the adjustment
 164                                 level for the Out-Of-Memory killer for
 165                                 executed processes. Takes an integer
 166                                 between -1000 (to disable OOM killing
 167                                 for this process) and 1000 (to make
 168                                 killing of this process under memory
 169                                 pressure very likely). See <ulink
 170                                 url="http://www.kernel.org/doc/Documentation/filesystems/proc.txt">proc.txt</ulink>
 171                                 for details.</para></listitem>
 172                         </varlistentry>
 173
 174                         <varlistentry>
 175                                 <term><varname>IOSchedulingClass=</varname></term>
 176
 177                                 <listitem><para>Sets the IO scheduling
 178                                 class for executed processes. Takes an
 179                                 integer between 0 and 3 or one of the
 180                                 strings <option>none</option>,
 181                                 <option>realtime</option>,
 182                                 <option>best-effort</option> or
 183                                 <option>idle</option>. See
 184                                 <citerefentry><refentrytitle>ioprio_set</refentrytitle><manvolnum>2</manvolnum></citerefentry>
 185                                 for details.</para></listitem>
 186                         </varlistentry>
 187
 188                         <varlistentry>
 189                                 <term><varname>IOSchedulingPriority=</varname></term>
 190
 191                                 <listitem><para>Sets the IO scheduling
 192                                 priority for executed processes. Takes
 193                                 an integer between 0 (highest
 194                                 priority) and 7 (lowest priority). The
 195                                 available priorities depend on the
 196                                 selected IO scheduling class (see
 197                                 above). See
 198                                 <citerefentry><refentrytitle>ioprio_set</refentrytitle><manvolnum>2</manvolnum></citerefentry>
 199                                 for details.</para></listitem>
 200                         </varlistentry>
 201
 202                         <varlistentry>
 203                                 <term><varname>CPUSchedulingPolicy=</varname></term>
 204
 205                                 <listitem><para>Sets the CPU
 206                                 scheduling policy for executed
 207                                 processes. Takes one of
 208                                 <option>other</option>,
 209                                 <option>batch</option>,
 210                                 <option>idle</option>,
 211                                 <option>fifo</option> or
 212                                 <option>rr</option>. See
 213                                 <citerefentry><refentrytitle>sched_setscheduler</refentrytitle><manvolnum>2</manvolnum></citerefentry>
 214                                 for details.</para></listitem>
 215                         </varlistentry>
 216
 217                         <varlistentry>
 218                                 <term><varname>CPUSchedulingPriority=</varname></term>
 219
 220                                 <listitem><para>Sets the CPU
 221                                 scheduling priority for executed
 222                                 processes. The available priority
 223                                 range depends on the selected CPU
 224                                 scheduling policy (see above). For
 225                                 real-time scheduling policies an
 226                                 integer between 1 (lowest priority)
 227                                 and 99 (highest priority) can be used.
 228                                 See <citerefentry><refentrytitle>sched_setscheduler</refentrytitle><manvolnum>2</manvolnum></citerefentry>
 229                                 for details.
 230                                 </para></listitem>
 231                         </varlistentry>
 232
 233                         <varlistentry>
 234                                 <term><varname>CPUSchedulingResetOnFork=</varname></term>
 235
 236                                 <listitem><para>Takes a boolean
 237                                 argument. If true elevated CPU
 238                                 scheduling priorities and policies
 239                                 will be reset when the executed
 240                                 processes fork, and can hence not leak
 241                                 into child processes. See
 242                                 <citerefentry><refentrytitle>sched_setscheduler</refentrytitle><manvolnum>2</manvolnum></citerefentry>
 243                                 for details. Defaults to false.</para></listitem>
 244                         </varlistentry>
 245
 246                         <varlistentry>
 247                                 <term><varname>CPUAffinity=</varname></term>
 248
 249                                 <listitem><para>Controls the CPU
 250                                 affinity of the executed
 251                                 processes. Takes a space-separated
 252                                 list of CPU indexes. This option may
 253                                 be specified more than once in which
 254                                 case the specificed CPU affinity masks
 255                                 are merged. If the empty string is
 256                                 assigned the mask is reset, all
 257                                 assignments prior to this will have no
 258                                 effect. See
 259                                 <citerefentry><refentrytitle>sched_setaffinity</refentrytitle><manvolnum>2</manvolnum></citerefentry>
 260                                 for details.</para></listitem>
 261                         </varlistentry>
 262
 263                         <varlistentry>
 264                                 <term><varname>UMask=</varname></term>
 265
 266                                 <listitem><para>Controls the file mode
 267                                 creation mask. Takes an access mode in
 268                                 octal notation. See
 269                                 <citerefentry><refentrytitle>umask</refentrytitle><manvolnum>2</manvolnum></citerefentry>
 270                                 for details. Defaults to
 271                                 0022.</para></listitem>
 272                         </varlistentry>
 273
 274                         <varlistentry>
 275                                 <term><varname>Environment=</varname></term>
 276
 277                                 <listitem><para>Sets environment
 278                                 variables for executed
 279                                 processes. Takes a space-separated
 280                                 list of variable assignments. This
 281                                 option may be specified more than once
 282                                 in which case all listed variables
 283                                 will be set. If the same variable is
 284                                 set twice the later setting will
 285                                 override the earlier setting. If the
 286                                 empty string is assigned to this
 287                                 option the list of environment
 288                                 variables is reset, all prior
 289                                 assignments have no effect. See
 290                                 <citerefentry><refentrytitle>environ</refentrytitle><manvolnum>7</manvolnum></citerefentry>
 291                                 for details.</para></listitem>
 292                         </varlistentry>
 293                         <varlistentry>
 294                                 <term><varname>EnvironmentFile=</varname></term>
 295                                 <listitem><para>Similar to
 296                                 <varname>Environment=</varname> but
 297                                 reads the environment variables from a
 298                                 text file. The text file should
 299                                 contain new-line separated variable
 300                                 assignments. Empty lines and lines
 301                                 starting with ; or # will be ignored,
 302                                 which may be used for commenting. A line
 303                                 ending with a backslash will be concatenated
 304                                 with the following one, allowing multiline variable
 305                                 definitions. The parser strips leading
 306                                 and trailing whitespace from the values
 307                                 of assignments, unless you use
 308                                 double quotes (").</para>
 309
 310                                 <para>The argument passed should be an
 311                                 absolute file name or wildcard
 312                                 expression, optionally prefixed with
 313                                 "-", which indicates that if the file
 314                                 does not exist it won't be read and no
 315                                 error or warning message is logged.
 316                                 This option may be specified more than
 317                                 once in which case all specified files
 318                                 are read. If the empty string is
 319                                 assigned to this option the list of
 320                                 file to read is reset, all prior
 321                                 assignments have no effect.</para>
 322
 323                                 <para>The files listed with this
 324                                 directive will be read shortly before
 325                                 the process is executed. Settings from
 326                                 these files override settings made
 327                                 with
 328                                 <varname>Environment=</varname>. If
 329                                 the same variable is set twice from
 330                                 these files the files will be read in
 331                                 the order they are specified and the
 332                                 later setting will override the
 333                                 earlier setting.</para></listitem>
 334                         </varlistentry>
 335
 336                         <varlistentry>
 337                                 <term><varname>StandardInput=</varname></term>
 338                                 <listitem><para>Controls where file
 339                                 descriptor 0 (STDIN) of the executed
 340                                 processes is connected to. Takes one
 341                                 of <option>null</option>,
 342                                 <option>tty</option>,
 343                                 <option>tty-force</option>,
 344                                 <option>tty-fail</option> or
 345                                 <option>socket</option>. If
 346                                 <option>null</option> is selected
 347                                 standard input will be connected to
 348                                 <filename>/dev/null</filename>,
 349                                 i.e. all read attempts by the process
 350                                 will result in immediate EOF. If
 351                                 <option>tty</option> is selected
 352                                 standard input is connected to a TTY
 353                                 (as configured by
 354                                 <varname>TTYPath=</varname>, see
 355                                 below) and the executed process
 356                                 becomes the controlling process of the
 357                                 terminal. If the terminal is already
 358                                 being controlled by another process the
 359                                 executed process waits until the current
 360                                 controlling process releases the
 361                                 terminal.
 362                                 <option>tty-force</option>
 363                                 is similar to <option>tty</option>,
 364                                 but the executed process is forcefully
 365                                 and immediately made the controlling
 366                                 process of the terminal, potentially
 367                                 removing previous controlling
 368                                 processes from the
 369                                 terminal. <option>tty-fail</option> is
 370                                 similar to <option>tty</option> but if
 371                                 the terminal already has a controlling
 372                                 process start-up of the executed
 373                                 process fails.  The
 374                                 <option>socket</option> option is only
 375                                 valid in socket-activated services,
 376                                 and only when the socket configuration
 377                                 file (see
 378                                 <citerefentry><refentrytitle>systemd.socket</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 379                                 for details) specifies a single socket
 380                                 only. If this option is set standard
 381                                 input will be connected to the socket
 382                                 the service was activated from, which
 383                                 is primarily useful for compatibility
 384                                 with daemons designed for use with the
 385                                 traditional
 386                                 <citerefentry><refentrytitle>inetd</refentrytitle><manvolnum>8</manvolnum></citerefentry>
 387                                 daemon. This setting defaults to
 388                                 <option>null</option>.</para></listitem>
 389                         </varlistentry>
 390                         <varlistentry>
 391                                 <term><varname>StandardOutput=</varname></term>
 392                                 <listitem><para>Controls where file
 393                                 descriptor 1 (STDOUT) of the executed
 394                                 processes is connected to. Takes one
 395                                 of <option>inherit</option>,
 396                                 <option>null</option>,
 397                                 <option>tty</option>,
 398                                 <option>syslog</option>,
 399                                 <option>kmsg</option>,
 400                                 <option>journal</option>,
 401                                 <option>syslog+console</option>,
 402                                 <option>kmsg+console</option>,
 403                                 <option>journal+console</option> or
 404                                 <option>socket</option>. If set to
 405                                 <option>inherit</option> the file
 406                                 descriptor of standard input is
 407                                 duplicated for standard output. If set
 408                                 to <option>null</option> standard
 409                                 output will be connected to
 410                                 <filename>/dev/null</filename>,
 411                                 i.e. everything written to it will be
 412                                 lost. If set to <option>tty</option>
 413                                 standard output will be connected to a
 414                                 tty (as configured via
 415                                 <varname>TTYPath=</varname>, see
 416                                 below). If the TTY is used for output
 417                                 only the executed process will not
 418                                 become the controlling process of the
 419                                 terminal, and will not fail or wait
 420                                 for other processes to release the
 421                                 terminal. <option>syslog</option>
 422                                 connects standard output to the
 423                                 <citerefentry><refentrytitle>syslog</refentrytitle><manvolnum>3</manvolnum></citerefentry>
 424                                 system syslog
 425                                 service. <option>kmsg</option>
 426                                 connects it with the kernel log buffer
 427                                 which is accessible via
 428                                 <citerefentry><refentrytitle>dmesg</refentrytitle><manvolnum>1</manvolnum></citerefentry>. <option>journal</option>
 429                                 connects it with the journal which is
 430                                 accessible via
 431                                 <citerefentry><refentrytitle>journalctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>
 432                                 (Note that everything that is written
 433                                 to syslog or kmsg is implicitly stored
 434                                 in the journal as well, those options
 435                                 are hence supersets of this
 436                                 one). <option>syslog+console</option>,
 437                                 <option>journal+console</option> and
 438                                 <option>kmsg+console</option> work
 439                                 similarly but copy the output to the
 440                                 system console as
 441                                 well. <option>socket</option> connects
 442                                 standard output to a socket from
 443                                 socket activation, semantics are
 444                                 similar to the respective option of
 445                                 <varname>StandardInput=</varname>.
 446                                 This setting defaults to the value set
 447                                 with
 448                                 <option>DefaultStandardOutput=</option>
 449                                 in
 450                                 <citerefentry><refentrytitle>systemd.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
 451                                 which defaults to
 452                                 <option>journal</option>.</para></listitem>
 453                         </varlistentry>
 454                         <varlistentry>
 455                                 <term><varname>StandardError=</varname></term>
 456                                 <listitem><para>Controls where file
 457                                 descriptor 2 (STDERR) of the executed
 458                                 processes is connected to. The
 459                                 available options are identical to
 460                                 those of
 461                                 <varname>StandardOutput=</varname>,
 462                                 with one exception: if set to
 463                                 <option>inherit</option> the file
 464                                 descriptor used for standard output is
 465                                 duplicated for standard error. This
 466                                 setting defaults to the value set with
 467                                 <option>DefaultStandardError=</option>
 468                                 in
 469                                 <citerefentry><refentrytitle>systemd.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
 470                                 which defaults to
 471                                 <option>inherit</option>.</para></listitem>
 472                         </varlistentry>
 473                         <varlistentry>
 474                                 <term><varname>TTYPath=</varname></term>
 475                                 <listitem><para>Sets the terminal
 476                                 device node to use if standard input,
 477                                 output or stderr are connected to a
 478                                 TTY (see above). Defaults to
 479                                 <filename>/dev/console</filename>.</para></listitem>
 480                         </varlistentry>
 481                         <varlistentry>
 482                                 <term><varname>TTYReset=</varname></term>
 483                                 <listitem><para>Reset the terminal
 484                                 device specified with
 485                                 <varname>TTYPath=</varname> before and
 486                                 after execution. Defaults to
 487                                 <literal>no</literal>.</para></listitem>
 488                         </varlistentry>
 489                         <varlistentry>
 490                                 <term><varname>TTYVHangup=</varname></term>
 491                                 <listitem><para>Disconnect all clients
 492                                 which have opened the terminal device
 493                                 specified with
 494                                 <varname>TTYPath=</varname>
 495                                 before and after execution. Defaults
 496                                 to
 497                                 <literal>no</literal>.</para></listitem>
 498                         </varlistentry>
 499                         <varlistentry>
 500                                 <term><varname>TTYVTDisallocate=</varname></term>
 501                                 <listitem><para>If the terminal
 502                                 device specified with
 503                                 <varname>TTYPath=</varname> is a
 504                                 virtual console terminal try to
 505                                 deallocate the TTY before and after
 506                                 execution. This ensures that the
 507                                 screen and scrollback buffer is
 508                                 cleared. Defaults to
 509                                 <literal>no</literal>.</para></listitem>
 510                         </varlistentry>
 511                         <varlistentry>
 512                                 <term><varname>SyslogIdentifier=</varname></term>
 513                                 <listitem><para>Sets the process name
 514                                 to prefix log lines sent to syslog or
 515                                 the kernel log buffer with. If not set
 516                                 defaults to the process name of the
 517                                 executed process. This option is only
 518                                 useful when
 519                                 <varname>StandardOutput=</varname> or
 520                                 <varname>StandardError=</varname> are
 521                                 set to <option>syslog</option> or
 522                                 <option>kmsg</option>.</para></listitem>
 523                         </varlistentry>
 524                         <varlistentry>
 525                                 <term><varname>SyslogFacility=</varname></term>
 526                                 <listitem><para>Sets the syslog
 527                                 facility to use when logging to
 528                                 syslog. One of <option>kern</option>,
 529                                 <option>user</option>,
 530                                 <option>mail</option>,
 531                                 <option>daemon</option>,
 532                                 <option>auth</option>,
 533                                 <option>syslog</option>,
 534                                 <option>lpr</option>,
 535                                 <option>news</option>,
 536                                 <option>uucp</option>,
 537                                 <option>cron</option>,
 538                                 <option>authpriv</option>,
 539                                 <option>ftp</option>,
 540                                 <option>local0</option>,
 541                                 <option>local1</option>,
 542                                 <option>local2</option>,
 543                                 <option>local3</option>,
 544                                 <option>local4</option>,
 545                                 <option>local5</option>,
 546                                 <option>local6</option> or
 547                                 <option>local7</option>. See
 548                                 <citerefentry><refentrytitle>syslog</refentrytitle><manvolnum>3</manvolnum></citerefentry>
 549                                 for details. This option is only
 550                                 useful when
 551                                 <varname>StandardOutput=</varname> or
 552                                 <varname>StandardError=</varname> are
 553                                 set to <option>syslog</option>.
 554                                 Defaults to
 555                                 <option>daemon</option>.</para></listitem>
 556                         </varlistentry>
 557                         <varlistentry>
 558                                 <term><varname>SyslogLevel=</varname></term>
 559                                 <listitem><para>Default syslog level
 560                                 to use when logging to syslog or the
 561                                 kernel log buffer. One of
 562                                 <option>emerg</option>,
 563                                 <option>alert</option>,
 564                                 <option>crit</option>,
 565                                 <option>err</option>,
 566                                 <option>warning</option>,
 567                                 <option>notice</option>,
 568                                 <option>info</option>,
 569                                 <option>debug</option>. See
 570                                 <citerefentry><refentrytitle>syslog</refentrytitle><manvolnum>3</manvolnum></citerefentry>
 571                                 for details. This option is only
 572                                 useful when
 573                                 <varname>StandardOutput=</varname> or
 574                                 <varname>StandardError=</varname> are
 575                                 set to <option>syslog</option> or
 576                                 <option>kmsg</option>. Note that
 577                                 individual lines output by the daemon
 578                                 might be prefixed with a different log
 579                                 level which can be used to override
 580                                 the default log level specified
 581                                 here. The interpretation of these
 582                                 prefixes may be disabled with
 583                                 <varname>SyslogLevelPrefix=</varname>,
 584                                 see below. For details see
 585                                 <citerefentry><refentrytitle>sd-daemon</refentrytitle><manvolnum>3</manvolnum></citerefentry>.
 586
 587                                 Defaults to
 588                                 <option>info</option>.</para></listitem>
 589                         </varlistentry>
 590
 591                         <varlistentry>
 592                                 <term><varname>SyslogLevelPrefix=</varname></term>
 593                                 <listitem><para>Takes a boolean
 594                                 argument. If true and
 595                                 <varname>StandardOutput=</varname> or
 596                                 <varname>StandardError=</varname> are
 597                                 set to <option>syslog</option>,
 598                                 <option>kmsg</option> or
 599                                 <option>journal</option>, log lines
 600                                 written by the executed process that
 601                                 are prefixed with a log level will be
 602                                 passed on to syslog with this log
 603                                 level set but the prefix removed. If
 604                                 set to false, the interpretation of
 605                                 these prefixes is disabled and the
 606                                 logged lines are passed on as-is. For
 607                                 details about this prefixing see
 608                                 <citerefentry><refentrytitle>sd-daemon</refentrytitle><manvolnum>3</manvolnum></citerefentry>.
 609                                 Defaults to true.</para></listitem>
 610                         </varlistentry>
 611
 612                         <varlistentry>
 613                                 <term><varname>TimerSlackNSec=</varname></term>
 614                                 <listitem><para>Sets the timer slack
 615                                 in nanoseconds for the executed
 616                                 processes. The timer slack controls
 617                                 the accuracy of wake-ups triggered by
 618                                 timers. See
 619                                 <citerefentry><refentrytitle>prctl</refentrytitle><manvolnum>2</manvolnum></citerefentry>
 620                                 for more information. Note that in
 621                                 contrast to most other time span
 622                                 definitions this parameter takes an
 623                                 integer value in nano-seconds if no
 624                                 unit is specified. The usual time
 625                                 units are understood
 626                                 too.</para></listitem>
 627                         </varlistentry>
 628
 629                         <varlistentry>
 630                                 <term><varname>LimitCPU=</varname></term>
 631                                 <term><varname>LimitFSIZE=</varname></term>
 632                                 <term><varname>LimitDATA=</varname></term>
 633                                 <term><varname>LimitSTACK=</varname></term>
 634                                 <term><varname>LimitCORE=</varname></term>
 635                                 <term><varname>LimitRSS=</varname></term>
 636                                 <term><varname>LimitNOFILE=</varname></term>
 637                                 <term><varname>LimitAS=</varname></term>
 638                                 <term><varname>LimitNPROC=</varname></term>
 639                                 <term><varname>LimitMEMLOCK=</varname></term>
 640                                 <term><varname>LimitLOCKS=</varname></term>
 641                                 <term><varname>LimitSIGPENDING=</varname></term>
 642                                 <term><varname>LimitMSGQUEUE=</varname></term>
 643                                 <term><varname>LimitNICE=</varname></term>
 644                                 <term><varname>LimitRTPRIO=</varname></term>
 645                                 <term><varname>LimitRTTIME=</varname></term>
 646                                 <listitem><para>These settings control
 647                                 various resource limits for executed
 648                                 processes. See
 649                                 <citerefentry><refentrytitle>setrlimit</refentrytitle><manvolnum>2</manvolnum></citerefentry>
 650                                 for details. Use the string
 651                                 <varname>infinity</varname> to
 652                                 configure no limit on a specific
 653                                 resource.</para></listitem>
 654                         </varlistentry>
 655
 656                         <varlistentry>
 657                                 <term><varname>PAMName=</varname></term>
 658                                 <listitem><para>Sets the PAM service
 659                                 name to set up a session as. If set
 660                                 the executed process will be
 661                                 registered as a PAM session under the
 662                                 specified service name. This is only
 663                                 useful in conjunction with the
 664                                 <varname>User=</varname> setting. If
 665                                 not set no PAM session will be opened
 666                                 for the executed processes. See
 667                                 <citerefentry><refentrytitle>pam</refentrytitle><manvolnum>8</manvolnum></citerefentry>
 668                                 for details.</para></listitem>
 669                         </varlistentry>
 670
 671                         <varlistentry>
 672                                 <term><varname>TCPWrapName=</varname></term>
 673                                 <listitem><para>If this is a
 674                                 socket-activated service this sets the
 675                                 tcpwrap service name to check the
 676                                 permission for the current connection
 677                                 with. This is only useful in
 678                                 conjunction with socket-activated
 679                                 services, and stream sockets (TCP) in
 680                                 particular. It has no effect on other
 681                                 socket types (e.g. datagram/UDP) and
 682                                 on processes unrelated to socket-based
 683                                 activation. If the tcpwrap
 684                                 verification fails daemon start-up
 685                                 will fail and the connection is
 686                                 terminated. See
 687                                 <citerefentry><refentrytitle>tcpd</refentrytitle><manvolnum>8</manvolnum></citerefentry>
 688                                 for details. Note that this option may
 689                                 be used to do access control checks
 690                                 only. Shell commands and commands
 691                                 described in
 692                                 <citerefentry><refentrytitle>hosts_options</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 693                                 are not supported.</para></listitem>
 694                         </varlistentry>
 695
 696                         <varlistentry>
 697                                 <term><varname>CapabilityBoundingSet=</varname></term>
 698
 699                                 <listitem><para>Controls which
 700                                 capabilities to include in the
 701                                 capability bounding set for the
 702                                 executed process. See
 703                                 <citerefentry><refentrytitle>capabilities</refentrytitle><manvolnum>7</manvolnum></citerefentry>
 704                                 for details. Takes a whitespace
 705                                 separated list of capability names as
 706                                 read by
 707                                 <citerefentry><refentrytitle>cap_from_name</refentrytitle><manvolnum>3</manvolnum></citerefentry>.
 708                                 Capabilities listed will be included
 709                                 in the bounding set, all others are
 710                                 removed. If the list of capabilities
 711                                 is prefixed with ~ all but the listed
 712                                 capabilities will be included, the
 713                                 effect of the assignment
 714                                 inverted. Note that this option also
 715                                 effects the respective capabilities in
 716                                 the effective, permitted and
 717                                 inheritable capability sets, on top of
 718                                 what <varname>Capabilities=</varname>
 719                                 does. If this option is not used the
 720                                 capability bounding set is not
 721                                 modified on process execution, hence
 722                                 no limits on the capabilities of the
 723                                 process are enforced. This option may
 724                                 appear more than once in which case
 725                                 the bounding sets are merged. If the empty
 726                                 string is assigned to this option the
 727                                 bounding set is reset, and all prior
 728                                 settings have no
 729                                 effect.</para></listitem>
 730                         </varlistentry>
 731
 732                         <varlistentry>
 733                                 <term><varname>SecureBits=</varname></term>
 734                                 <listitem><para>Controls the secure
 735                                 bits set for the executed process. See
 736                                 <citerefentry><refentrytitle>capabilities</refentrytitle><manvolnum>7</manvolnum></citerefentry>
 737                                 for details. Takes a list of strings:
 738                                 <option>keep-caps</option>,
 739                                 <option>keep-caps-locked</option>,
 740                                 <option>no-setuid-fixup</option>,
 741                                 <option>no-setuid-fixup-locked</option>,
 742                                 <option>noroot</option> and/or
 743                                 <option>noroot-locked</option>. This
 744                                 option may appear more than once in
 745                                 which case the secure bits are
 746                                 ORed. If the empty string is assigned
 747                                 to this option the bits are reset to
 748                                 0.</para></listitem>
 749                         </varlistentry>
 750
 751                         <varlistentry>
 752                                 <term><varname>Capabilities=</varname></term>
 753                                 <listitem><para>Controls the
 754                                 <citerefentry><refentrytitle>capabilities</refentrytitle><manvolnum>7</manvolnum></citerefentry>
 755                                 set for the executed process. Take a
 756                                 capability string describing the
 757                                 effective, permitted and inherited
 758                                 capability sets as documented in
 759                                 <citerefentry><refentrytitle>cap_from_text</refentrytitle><manvolnum>3</manvolnum></citerefentry>.
 760                                 Note that these capability sets are
 761                                 usually influenced by the capabilities
 762                                 attached to the executed file. Due to
 763                                 that
 764                                 <varname>CapabilityBoundingSet=</varname>
 765                                 is probably the much more useful
 766                                 setting.</para></listitem>
 767                         </varlistentry>
 768
 769                         <varlistentry>
 770                                 <term><varname>ControlGroup=</varname></term>
 771
 772                                 <listitem><para>Controls the control
 773                                 groups the executed processes shall be
 774                                 made members of. Takes a
 775                                 space-separated list of cgroup
 776                                 identifiers. A cgroup identifier is
 777                                 formatted like
 778                                 <filename>cpu:/foo/bar</filename>,
 779                                 where "cpu" indicates the kernel
 780                                 control group controller used, and
 781                                 <filename>/foo/bar</filename> is the
 782                                 control group path. The controller
 783                                 name and ":" may be omitted in which
 784                                 case the named systemd control group
 785                                 hierarchy is implied. Alternatively,
 786                                 the path and ":" may be omitted, in
 787                                 which case the default control group
 788                                 path for this unit is implied.</para>
 789
 790                                 <para>This option may be used to place
 791                                 executed processes in arbitrary groups
 792                                 in arbitrary hierarchies -- which may
 793                                 then be externally configured with
 794                                 additional execution limits. By
 795                                 default systemd will place all
 796                                 executed processes in separate
 797                                 per-unit control groups (named after
 798                                 the unit) in the systemd named
 799                                 hierarchy. This option is primarily
 800                                 intended to place executed processes
 801                                 in specific paths in specific kernel
 802                                 controller hierarchies. It is not
 803                                 recommended to manipulate the service
 804                                 control group path in the systemd
 805                                 named hierarchy. For details about
 806                                 control groups see <ulink
 807                                 url="http://www.kernel.org/doc/Documentation/cgroups/cgroups.txt">cgroups.txt</ulink>.</para>
 808
 809                                 <para>This option may appear more than
 810                                 once, in which case the list of
 811                                 control group assignments is
 812                                 merged. If the same hierarchy gets two
 813                                 different paths assigned only the
 814                                 later setting will take effect. If the
 815                                 empty string is assigned to this
 816                                 option the list of control group
 817                                 assignments is reset, all previous
 818                                 assignments will have no
 819                                 effect.</para>
 820
 821                                 <para>Note that the list of control
 822                                 group assignments of a unit is
 823                                 extended implicitly based on the
 824                                 settings of
 825                                 <varname>DefaultControllers=</varname>
 826                                 of
 827                                 <citerefentry><refentrytitle>systemd.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
 828                                 but a unit's
 829                                 <varname>ControlGroup=</varname>
 830                                 setting for a specific controller
 831                                 takes precedence.</para></listitem>
 832                         </varlistentry>
 833
 834                         <varlistentry>
 835                                 <term><varname>ControlGroupModify=</varname></term>
 836                                 <listitem><para>Takes a boolean
 837                                 argument. If true, the control groups
 838                                 created for this unit will be owned by
 839                                 the user specified with
 840                                 <varname>User=</varname> (and the
 841                                 appropriate group), and he/she can create
 842                                 subgroups as well as add processes to
 843                                 the group.</para></listitem>
 844                         </varlistentry>
 845
 846                         <varlistentry>
 847                                 <term><varname>ControlGroupPersistent=</varname></term>
 848                                 <listitem><para>Takes a boolean
 849                                 argument. If true, the control groups
 850                                 created for this unit will be marked
 851                                 to be persistent, i.e. systemd will
 852                                 not remove them when stopping the
 853                                 unit. The default is false, meaning
 854                                 that the control groups will be
 855                                 removed when the unit is stopped. For
 856                                 details about the semantics of this
 857                                 logic see <ulink
 858                                 url="http://www.freedesktop.org/wiki/Software/systemd/PaxControlGroups">PaxControlGroups</ulink>.</para></listitem>
 859                         </varlistentry>
 860
 861                         <varlistentry>
 862                                 <term><varname>ControlGroupAttribute=</varname></term>
 863
 864                                 <listitem><para>Set a specific control
 865                                 group attribute for executed
 866                                 processes, and (if needed) add the
 867                                 executed processes to a cgroup in the
 868                                 hierarchy of the controller the
 869                                 attribute belongs to. Takes two
 870                                 space-separated arguments: the
 871                                 attribute name (syntax is
 872                                 <literal>cpu.shares</literal> where
 873                                 <literal>cpu</literal> refers to a
 874                                 specific controller and
 875                                 <literal>shares</literal> to the
 876                                 attribute name), and the attribute
 877                                 value. Example:
 878                                 <literal>ControlGroupAttribute=cpu.shares
 879                                 512</literal>. If this option is used
 880                                 for an attribute that belongs to a
 881                                 kernel controller hierarchy the unit
 882                                 is not already configured to be added
 883                                 to (for example via the
 884                                 <literal>ControlGroup=</literal>
 885                                 option) then the unit will be added to
 886                                 the controller and the default unit
 887                                 cgroup path is implied. Thus, using
 888                                 <varname>ControlGroupAttribute=</varname>
 889                                 is in most cases sufficient to make
 890                                 use of control group enforcements,
 891                                 explicit
 892                                 <varname>ControlGroup=</varname> are
 893                                 only necessary in case the implied
 894                                 default control group path for a
 895                                 service is not desirable. For details
 896                                 about control group attributes see
 897                                 <ulink
 898                                 url="http://www.kernel.org/doc/Documentation/cgroups/cgroups.txt">cgroups.txt</ulink>. This
 899                                 option may appear more than once, in
 900                                 order to set multiple control group
 901                                 attributes. If this option is used
 902                                 multiple times for the same cgroup
 903                                 attribute only the later setting takes
 904                                 effect. If the empty string is
 905                                 assigned to this option the list of
 906                                 attributes is reset, all previous
 907                                 cgroup attribute settings have no
 908                                 effect, including those done with
 909                                 <varname>CPUShares=</varname>,
 910                                 <varname>MemoryLimit=</varname>,
 911                                 <varname>MemorySoftLimit</varname>,
 912                                 <varname>DeviceAllow=</varname>,
 913                                 <varname>DeviceDeny=</varname>,
 914                                 <varname>BlockIOWeight=</varname>,
 915                                 <varname>BlockIOReadBandwidth=</varname>,
 916                                 <varname>BlockIOWriteBandwidth=</varname>.
 917                                 </para></listitem>
 918                         </varlistentry>
 919
 920                         <varlistentry>
 921                                 <term><varname>CPUShares=</varname></term>
 922
 923                                 <listitem><para>Assign the specified
 924                                 overall CPU time shares to the
 925                                 processes executed. Takes an integer
 926                                 value. This controls the
 927                                 <literal>cpu.shares</literal> control
 928                                 group attribute, which defaults to
 929                                 1024. For details about this control
 930                                 group attribute see <ulink
 931                                 url="http://www.kernel.org/doc/Documentation/scheduler/sched-design-CFS.txt">sched-design-CFS.txt</ulink>.</para></listitem>
 932                         </varlistentry>
 933
 934                         <varlistentry>
 935                                 <term><varname>MemoryLimit=</varname></term>
 936                                 <term><varname>MemorySoftLimit=</varname></term>
 937
 938                                 <listitem><para>Limit the overall memory usage
 939                                 of the executed processes to a certain
 940                                 size. Takes a memory size in bytes. If
 941                                 the value is suffixed with K, M, G or
 942                                 T the specified memory size is parsed
 943                                 as Kilobytes, Megabytes, Gigabytes,
 944                                 or Terabytes (to the base
 945                                 1024), respectively. This controls the
 946                                 <literal>memory.limit_in_bytes</literal>
 947                                 and
 948                                 <literal>memory.soft_limit_in_bytes</literal>
 949                                 control group attributes. For details
 950                                 about these control group attributes
 951                                 see <ulink
 952                                 url="http://www.kernel.org/doc/Documentation/cgroups/memory.txt">memory.txt</ulink>.</para></listitem>
 953                         </varlistentry>
 954
 955                         <varlistentry>
 956                                 <term><varname>DeviceAllow=</varname></term>
 957                                 <term><varname>DeviceDeny=</varname></term>
 958
 959                                 <listitem><para>Control access to
 960                                 specific device nodes by the executed processes. Takes two
 961                                 space separated strings: a device node
 962                                 path (such as
 963                                 <filename>/dev/null</filename>)
 964                                 followed by a combination of r, w, m
 965                                 to control reading, writing, or
 966                                 creating of the specific device node
 967                                 by the unit, respectively. This controls the
 968                                 <literal>devices.allow</literal>
 969                                 and
 970                                 <literal>devices.deny</literal>
 971                                 control group attributes. For details
 972                                 about these control group attributes
 973                                 see <ulink
 974                                 url="http://www.kernel.org/doc/Documentation/cgroups/devices.txt">devices.txt</ulink>.</para></listitem>
 975                         </varlistentry>
 976
 977                         <varlistentry>
 978                                 <term><varname>BlockIOWeight=</varname></term>
 979
 980                                 <listitem><para>Set the default or
 981                                 per-device overall block IO weight
 982                                 value for the executed
 983                                 processes. Takes either a single
 984                                 weight value (between 10 and 1000) to
 985                                 set the default block IO weight, or a
 986                                 space separated pair of a file path
 987                                 and a weight value to specify the
 988                                 device specific weight value (Example:
 989                                 "/dev/sda 500"). The file path may be
 990                                 specified as path to a block device
 991                                 node or as any other file in which
 992                                 case the backing block device of the
 993                                 file system of the file is
 994                                 determined. This controls the
 995                                 <literal>blkio.weight</literal> and
 996                                 <literal>blkio.weight_device</literal>
 997                                 control group attributes, which
 998                                 default to 1000. Use this option
 999                                 multiple times to set weights for
1000                                 multiple devices. For details about
1001                                 these control group attributes see
1002                                 <ulink
1003                                 url="http://www.kernel.org/doc/Documentation/cgroups/blkio-controller.txt">blkio-controller.txt</ulink>.</para></listitem>
1004                         </varlistentry>
1005
1006                         <varlistentry>
1007                                 <term><varname>BlockIOReadBandwidth=</varname></term>
1008                                 <term><varname>BlockIOWriteBandwidth=</varname></term>
1009
1010                                 <listitem><para>Set the per-device
1011                                 overall block IO bandwidth limit for
1012                                 the executed processes. Takes a space
1013                                 separated pair of a file path and a
1014                                 bandwidth value (in bytes per second)
1015                                 to specify the device specific
1016                                 bandwidth. The file path may be
1017                                 specified as path to a block device
1018                                 node or as any other file in which
1019                                 case the backing block device of the
1020                                 file system of the file is determined.
1021                                 If the bandwidth is suffixed with K, M,
1022                                 G, or T the specified bandwidth is
1023                                 parsed as Kilobytes, Megabytes,
1024                                 Gigabytes, or Terabytes, respectively (Example:
1025                                 "/dev/disk/by-path/pci-0000:00:1f.2-scsi-0:0:0:0
1026                                 5M"). This controls the
1027                                 <literal>blkio.read_bps_device</literal>
1028                                 and
1029                                 <literal>blkio.write_bps_device</literal>
1030                                 control group attributes. Use this
1031                                 option multiple times to set bandwidth
1032                                 limits for multiple devices. For
1033                                 details about these control group
1034                                 attributes see <ulink
1035                                 url="http://www.kernel.org/doc/Documentation/cgroups/blkio-controller.txt">blkio-controller.txt</ulink>.</para></listitem>
1036                         </varlistentry>
1037
1038                         <varlistentry>
1039                                 <term><varname>ReadWriteDirectories=</varname></term>
1040                                 <term><varname>ReadOnlyDirectories=</varname></term>
1041                                 <term><varname>InaccessibleDirectories=</varname></term>
1042
1043                                 <listitem><para>Sets up a new
1044                                 file-system name space for executed
1045                                 processes. These options may be used
1046                                 to limit access a process might have
1047                                 to the main file-system
1048                                 hierarchy. Each setting takes a
1049                                 space-separated list of absolute
1050                                 directory paths. Directories listed in
1051                                 <varname>ReadWriteDirectories=</varname>
1052                                 are accessible from within the
1053                                 namespace with the same access rights
1054                                 as from outside. Directories listed in
1055                                 <varname>ReadOnlyDirectories=</varname>
1056                                 are accessible for reading only,
1057                                 writing will be refused even if the
1058                                 usual file access controls would
1059                                 permit this. Directories listed in
1060                                 <varname>InaccessibleDirectories=</varname>
1061                                 will be made inaccessible for
1062                                 processes inside the namespace. Note
1063                                 that restricting access with these
1064                                 options does not extend to submounts
1065                                 of a directory. You must list
1066                                 submounts separately in these settings
1067                                 to ensure the same limited
1068                                 access. These options may be specified
1069                                 more than once in which case all
1070                                 directories listed will have limited
1071                                 access from within the namespace. If
1072                                 the empty string is assigned to this
1073                                 option the specific list is reset, and
1074                                 all prior assignments have no
1075                                 effect.</para></listitem>
1076                         </varlistentry>
1077
1078                         <varlistentry>
1079                                 <term><varname>PrivateTmp=</varname></term>
1080
1081                                 <listitem><para>Takes a boolean
1082                                 argument. If true sets up a new file
1083                                 system namespace for the executed
1084                                 processes and mounts a private
1085                                 <filename>/tmp</filename> directory
1086                                 inside it, that is not shared by
1087                                 processes outside of the
1088                                 namespace. This is useful to secure
1089                                 access to temporary files of the
1090                                 process, but makes sharing between
1091                                 processes via
1092                                 <filename>/tmp</filename>
1093                                 impossible. Defaults to
1094                                 false.</para></listitem>
1095                         </varlistentry>
1096
1097                         <varlistentry>
1098                                 <term><varname>PrivateNetwork=</varname></term>
1099
1100                                 <listitem><para>Takes a boolean
1101                                 argument. If true sets up a new
1102                                 network namespace for the executed
1103                                 processes and configures only the
1104                                 loopback network device
1105                                 <literal>lo</literal> inside it. No
1106                                 other network devices will be
1107                                 available to the executed process.
1108                                 This is useful to securely turn off
1109                                 network access by the executed
1110                                 process. Defaults to
1111                                 false.</para></listitem>
1112                         </varlistentry>
1113
1114                         <varlistentry>
1115                                 <term><varname>MountFlags=</varname></term>
1116
1117                                 <listitem><para>Takes a mount
1118                                 propagation flag:
1119                                 <option>shared</option>,
1120                                 <option>slave</option> or
1121                                 <option>private</option>, which
1122                                 control whether the file system
1123                                 namespace set up for this unit's
1124                                 processes will receive or propagate
1125                                 new mounts. See
1126                                 <citerefentry><refentrytitle>mount</refentrytitle><manvolnum>2</manvolnum></citerefentry>
1127                                 for details. Default to
1128                                 <option>shared</option>.</para></listitem>
1129                         </varlistentry>
1130
1131                         <varlistentry>
1132                                 <term><varname>UtmpIdentifier=</varname></term>
1133
1134                                 <listitem><para>Takes a four
1135                                 character identifier string for an
1136                                 utmp/wtmp entry for this service. This
1137                                 should only be set for services such
1138                                 as <command>getty</command>
1139                                 implementations where utmp/wtmp
1140                                 entries must be created and cleared
1141                                 before and after execution. If the
1142                                 configured string is longer than four
1143                                 characters it is truncated and the
1144                                 terminal four characters are
1145                                 used. This setting interprets %I style
1146                                 string replacements. This setting is
1147                                 unset by default, i.e. no utmp/wtmp
1148                                 entries are created or cleaned up for
1149                                 this service.</para></listitem>
1150                         </varlistentry>
1151
1152                         <varlistentry>
1153                                 <term><varname>IgnoreSIGPIPE=</varname></term>
1154
1155                                 <listitem><para>Takes a boolean
1156                                 argument. If true causes SIGPIPE to be
1157                                 ignored in the executed
1158                                 process. Defaults to true, since
1159                                 SIGPIPE generally is useful only in
1160                                 shell pipelines.</para></listitem>
1161                         </varlistentry>
1162
1163                         <varlistentry>
1164                                 <term><varname>NoNewPrivileges=</varname></term>
1165
1166                                 <listitem><para>Takes a boolean
1167                                 argument. If true ensures that the
1168                                 service process and all its children
1169                                 can never gain new privileges. This
1170                                 option is more powerful than the respective
1171                                 secure bits flags (see above), as it
1172                                 also prohibits UID changes of any
1173                                 kind. This is the simplest, most
1174                                 effective way to ensure that a process
1175                                 and its children can never elevate
1176                                 privileges again.</para></listitem>
1177                         </varlistentry>
1178
1179                         <varlistentry>
1180                                 <term><varname>SystemCallFilter=</varname></term>
1181
1182                                 <listitem><para>Takes a space
1183                                 separated list of system call
1184                                 names. If this setting is used all
1185                                 system calls executed by the unit
1186                                 process except for the listed ones
1187                                 will result in immediate process
1188                                 termination with the SIGSYS signal
1189                                 (whitelisting). If the first character
1190                                 of the list is <literal>~</literal>
1191                                 the effect is inverted: only the
1192                                 listed system calls will result in
1193                                 immediate process termination
1194                                 (blacklisting). If this option is used
1195                                 <varname>NoNewPrivileges=yes</varname>
1196                                 is implied. This feature makes use of
1197                                 the Secure Computing Mode 2 interfaces
1198                                 of the kernel ('seccomp filtering')
1199                                 and is useful for enforcing a minimal
1200                                 sandboxing environment. Note that the
1201                                 <function>execve</function>,
1202                                 <function>rt_sigreturn</function>,
1203                                 <function>sigreturn</function>,
1204                                 <function>exit_group</function>,
1205                                 <function>exit</function> system calls
1206                                 are implicitly whitelisted and don't
1207                                 need to be listed explicitly. This
1208                                 option may be specified more than once
1209                                 in which case the filter masks are
1210                                 merged. If the empty string is
1211                                 assigned the filter is reset, all
1212                                 prior assignments will have no
1213                                 effect.</para></listitem>
1214                         </varlistentry>
1215
1216                 </variablelist>
1217         </refsect1>
1218
1219         <refsect1>
1220                   <title>See Also</title>
1221                   <para>
1222                           <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
1223                           <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
1224                           <citerefentry><refentrytitle>journalctl</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
1225                           <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
1226                           <citerefentry><refentrytitle>systemd.service</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
1227                           <citerefentry><refentrytitle>systemd.socket</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
1228                           <citerefentry><refentrytitle>systemd.swap</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
1229                           <citerefentry><refentrytitle>systemd.mount</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
1230                           <citerefentry><refentrytitle>systemd.kill</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
1231                           <citerefentry><refentrytitle>systemd.directives</refentrytitle><manvolnum>7</manvolnum></citerefentry>
1232                   </para>
1233         </refsect1>
1234
1235 </refentry>