man/systemd-system.conf.xml

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  10
  11   This file is part of systemd.
  12
  13   Copyright 2010 Lennart Poettering
  14
  15   systemd is free software; you can redistribute it and/or modify it
  16   under the terms of the GNU Lesser General Public License as published by
  17   the Free Software Foundation; either version 2.1 of the License, or
  18   (at your option) any later version.
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  23   Lesser General Public License for more details.
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  28
  29 <refentry id="systemd-system.conf"
  30     xmlns:xi="http://www.w3.org/2001/XInclude">
  31   <refentryinfo>
  32     <title>systemd-system.conf</title>
  33     <productname>systemd</productname>
  34
  35     <authorgroup>
  36       <author>
  37         <contrib>Developer</contrib>
  38         <firstname>Lennart</firstname>
  39         <surname>Poettering</surname>
  40         <email>lennart@poettering.net</email>
  41       </author>
  42     </authorgroup>
  43   </refentryinfo>
  44
  45   <refmeta>
  46     <refentrytitle>systemd-system.conf</refentrytitle>
  47     <manvolnum>5</manvolnum>
  48   </refmeta>
  49
  50   <refnamediv>
  51     <refname>systemd-system.conf</refname>
  52     <refname>system.conf.d</refname>
  53     <refname>systemd-user.conf</refname>
  54     <refname>user.conf.d</refname>
  55     <refpurpose>System and session service manager configuration files</refpurpose>
  56   </refnamediv>
  57
  58   <refsynopsisdiv>
  59     <para><filename>/etc/systemd/system.conf</filename>,
  60     <filename>/etc/systemd/system.conf.d/*.conf</filename>,
  61     <filename>/run/systemd/system.conf.d/*.conf</filename>,
  62     <filename>/usr/lib/systemd/system.conf.d/*.conf</filename></para>
  63     <para><filename>/etc/systemd/user.conf</filename>,
  64     <filename>/etc/systemd/user.conf.d/*.conf</filename>,
  65     <filename>/run/systemd/user.conf.d/*.conf</filename>,
  66     <filename>/usr/lib/systemd/user.conf.d/*.conf</filename></para>
  67   </refsynopsisdiv>
  68
  69   <refsect1>
  70     <title>Description</title>
  71
  72     <para>When run as a system instance, systemd interprets the
  73     configuration file <filename>system.conf</filename> and the files
  74     in <filename>system.conf.d</filename> directories; when run as a
  75     user instance, systemd interprets the configuration file
  76     <filename>user.conf</filename> and the files in
  77     <filename>user.conf.d</filename> directories. These configuration
  78     files contain a few settings controlling basic manager
  79     operations.</para>
  80   </refsect1>
  81
  82   <xi:include href="standard-conf.xml" xpointer="main-conf" />
  83
  84   <refsect1>
  85     <title>Options</title>
  86
  87     <para>All options are configured in the
  88     <literal>[Manager]</literal> section:</para>
  89
  90     <variablelist class='systemd-directives'>
  91
  92       <varlistentry>
  93         <term><varname>LogLevel=</varname></term>
  94         <term><varname>LogTarget=</varname></term>
  95         <term><varname>LogColor=</varname></term>
  96         <term><varname>LogLocation=</varname></term>
  97         <term><varname>DumpCore=yes</varname></term>
  98         <term><varname>CrashChangeVT=no</varname></term>
  99         <term><varname>CrashShell=no</varname></term>
 100         <term><varname>CrashReboot=no</varname></term>
 101         <term><varname>ShowStatus=yes</varname></term>
 102         <term><varname>DefaultStandardOutput=journal</varname></term>
 103         <term><varname>DefaultStandardError=inherit</varname></term>
 104
 105         <listitem><para>Configures various parameters of basic manager operation. These options may be overridden by
 106         the respective process and kernel command line arguments. See
 107         <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry> for
 108         details.</para></listitem>
 109       </varlistentry>
 110
 111       <varlistentry>
 112         <term><varname>CtrlAltDelBurstAction=</varname></term>
 113
 114         <listitem><para>Defines what action will be performed
 115         if user presses Ctrl-Alt-Delete more than 7 times in 2s.
 116         Can be set to <literal>reboot-force</literal>, <literal>poweroff-force</literal>,
 117         <literal>reboot-immediate</literal>, <literal>poweroff-immediate</literal>
 118         or disabled with <literal>none</literal>. Defaults to
 119         <literal>reboot-force</literal>.
 120         </para></listitem>
 121       </varlistentry>
 122
 123       <varlistentry>
 124         <term><varname>CPUAffinity=</varname></term>
 125
 126         <listitem><para>Configures the initial CPU affinity for the
 127         init process. Takes a list of CPU indices or ranges separated
 128         by either whitespace or commas. CPU ranges are specified by
 129         the lower and upper CPU indices separated by a
 130         dash.</para></listitem>
 131       </varlistentry>
 132
 133       <varlistentry>
 134         <term><varname>JoinControllers=cpu,cpuacct net_cls,netprio</varname></term>
 135
 136         <listitem><para>Configures controllers that shall be mounted
 137         in a single hierarchy. By default, systemd will mount all
 138         controllers which are enabled in the kernel in individual
 139         hierarchies, with the exception of those listed in this
 140         setting. Takes a space-separated list of comma-separated
 141         controller names, in order to allow multiple joined
 142         hierarchies. Defaults to 'cpu,cpuacct'. Pass an empty string
 143         to ensure that systemd mounts all controllers in separate
 144         hierarchies.</para>
 145
 146         <para>Note that this option is only applied once, at very
 147         early boot. If you use an initial RAM disk (initrd) that uses
 148         systemd, it might hence be necessary to rebuild the initrd if
 149         this option is changed, and make sure the new configuration
 150         file is included in it. Otherwise, the initrd might mount the
 151         controller hierarchies in a different configuration than
 152         intended, and the main system cannot remount them
 153         anymore.</para></listitem>
 154       </varlistentry>
 155
 156       <varlistentry>
 157         <term><varname>RuntimeWatchdogSec=</varname></term>
 158         <term><varname>ShutdownWatchdogSec=</varname></term>
 159
 160         <listitem><para>Configure the hardware watchdog at runtime and
 161         at reboot. Takes a timeout value in seconds (or in other time
 162         units if suffixed with <literal>ms</literal>,
 163         <literal>min</literal>, <literal>h</literal>,
 164         <literal>d</literal>, <literal>w</literal>). If
 165         <varname>RuntimeWatchdogSec=</varname> is set to a non-zero
 166         value, the watchdog hardware
 167         (<filename>/dev/watchdog</filename> or the path specified with
 168         <varname>WatchdogDevice=</varname> or the kernel option
 169         <varname>systemd.watchdog-device=</varname>) will be programmed
 170         to automatically reboot the system if it is not contacted within
 171         the specified timeout interval. The system manager will ensure
 172         to contact it at least once in half the specified timeout
 173         interval. This feature requires a hardware watchdog device to
 174         be present, as it is commonly the case in embedded and server
 175         systems. Not all hardware watchdogs allow configuration of the
 176         reboot timeout, in which case the closest available timeout is
 177         picked. <varname>ShutdownWatchdogSec=</varname> may be used to
 178         configure the hardware watchdog when the system is asked to
 179         reboot. It works as a safety net to ensure that the reboot
 180         takes place even if a clean reboot attempt times out. By
 181         default <varname>RuntimeWatchdogSec=</varname> defaults to 0
 182         (off), and <varname>ShutdownWatchdogSec=</varname> to 10min.
 183         These settings have no effect if a hardware watchdog is not
 184         available.</para></listitem>
 185       </varlistentry>
 186
 187       <varlistentry>
 188         <term><varname>WatchdogDevice=</varname></term>
 189
 190         <listitem><para>Configure the hardware watchdog device that the
 191         runtime and shutdown watchdog timers will open and use. Defaults
 192         to <filename>/dev/watchdog</filename>. This setting has no
 193         effect if a hardware watchdog is not available.</para></listitem>
 194       </varlistentry>
 195
 196       <varlistentry>
 197         <term><varname>CapabilityBoundingSet=</varname></term>
 198
 199         <listitem><para>Controls which capabilities to include in the
 200         capability bounding set for PID 1 and its children. See
 201         <citerefentry project='man-pages'><refentrytitle>capabilities</refentrytitle><manvolnum>7</manvolnum></citerefentry>
 202         for details. Takes a whitespace-separated list of capability
 203         names as read by
 204         <citerefentry project='mankier'><refentrytitle>cap_from_name</refentrytitle><manvolnum>3</manvolnum></citerefentry>.
 205         Capabilities listed will be included in the bounding set, all
 206         others are removed. If the list of capabilities is prefixed
 207         with ~, all but the listed capabilities will be included, the
 208         effect of the assignment inverted. Note that this option also
 209         affects the respective capabilities in the effective,
 210         permitted and inheritable capability sets. The capability
 211         bounding set may also be individually configured for units
 212         using the <varname>CapabilityBoundingSet=</varname> directive
 213         for units, but note that capabilities dropped for PID 1 cannot
 214         be regained in individual units, they are lost for
 215         good.</para></listitem>
 216       </varlistentry>
 217
 218       <varlistentry>
 219         <term><varname>SystemCallArchitectures=</varname></term>
 220
 221         <listitem><para>Takes a space-separated list of architecture
 222         identifiers. Selects from which architectures system calls may
 223         be invoked on this system. This may be used as an effective
 224         way to disable invocation of non-native binaries system-wide,
 225         for example to prohibit execution of 32-bit x86 binaries on
 226         64-bit x86-64 systems. This option operates system-wide, and
 227         acts similar to the
 228         <varname>SystemCallArchitectures=</varname> setting of unit
 229         files, see
 230         <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 231         for details. This setting defaults to the empty list, in which
 232         case no filtering of system calls based on architecture is
 233         applied. Known architecture identifiers are
 234         <literal>x86</literal>, <literal>x86-64</literal>,
 235         <literal>x32</literal>, <literal>arm</literal> and the special
 236         identifier <literal>native</literal>. The latter implicitly
 237         maps to the native architecture of the system (or more
 238         specifically, the architecture the system manager was compiled
 239         for). Set this setting to <literal>native</literal> to
 240         prohibit execution of any non-native binaries. When a binary
 241         executes a system call of an architecture that is not listed
 242         in this setting, it will be immediately terminated with the
 243         SIGSYS signal.</para></listitem>
 244       </varlistentry>
 245
 246       <varlistentry>
 247         <term><varname>TimerSlackNSec=</varname></term>
 248
 249         <listitem><para>Sets the timer slack in nanoseconds for PID 1,
 250         which is inherited by all executed processes, unless
 251         overridden individually, for example with the
 252         <varname>TimerSlackNSec=</varname> setting in service units
 253         (for details see
 254         <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>).
 255         The timer slack controls the accuracy of wake-ups triggered by
 256         system timers. See
 257         <citerefentry><refentrytitle>prctl</refentrytitle><manvolnum>2</manvolnum></citerefentry>
 258         for more information. Note that in contrast to most other time
 259         span definitions this parameter takes an integer value in
 260         nano-seconds if no unit is specified. The usual time units are
 261         understood too.</para></listitem>
 262       </varlistentry>
 263
 264       <varlistentry>
 265         <term><varname>DefaultTimerAccuracySec=</varname></term>
 266
 267         <listitem><para>Sets the default accuracy of timer units. This
 268         controls the global default for the
 269         <varname>AccuracySec=</varname> setting of timer units, see
 270         <citerefentry><refentrytitle>systemd.timer</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 271         for details. <varname>AccuracySec=</varname> set in individual
 272         units override the global default for the specific unit.
 273         Defaults to 1min. Note that the accuracy of timer units is
 274         also affected by the configured timer slack for PID 1, see
 275         <varname>TimerSlackNSec=</varname> above.</para></listitem>
 276       </varlistentry>
 277
 278       <varlistentry>
 279         <term><varname>DefaultTimeoutStartSec=</varname></term>
 280         <term><varname>DefaultTimeoutStopSec=</varname></term>
 281         <term><varname>DefaultRestartSec=</varname></term>
 282
 283         <listitem><para>Configures the default timeouts for starting
 284         and stopping of units, as well as the default time to sleep
 285         between automatic restarts of units, as configured per-unit in
 286         <varname>TimeoutStartSec=</varname>,
 287         <varname>TimeoutStopSec=</varname> and
 288         <varname>RestartSec=</varname> (for services, see
 289         <citerefentry><refentrytitle>systemd.service</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 290         for details on the per-unit settings). For non-service units,
 291         <varname>DefaultTimeoutStartSec=</varname> sets the default
 292         <varname>TimeoutSec=</varname>
 293         value. <varname>DefaultTimeoutStartSec=</varname> and
 294         <varname>DefaultTimeoutStopSec=</varname> default to
 295         90s. <varname>DefaultRestartSec=</varname> defaults to
 296         100ms.</para></listitem>
 297       </varlistentry>
 298
 299       <varlistentry>
 300         <term><varname>DefaultStartLimitIntervalSec=</varname></term>
 301         <term><varname>DefaultStartLimitBurst=</varname></term>
 302
 303         <listitem><para>Configure the default unit start rate
 304         limiting, as configured per-service by
 305         <varname>StartLimitIntervalSec=</varname> and
 306         <varname>StartLimitBurst=</varname>. See
 307         <citerefentry><refentrytitle>systemd.service</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 308         for details on the per-service settings.
 309         <varname>DefaultStartLimitIntervalSec=</varname> defaults to
 310         10s. <varname>DefaultStartLimitBurst=</varname> defaults to
 311         5.</para></listitem>
 312       </varlistentry>
 313
 314       <varlistentry>
 315         <term><varname>DefaultEnvironment=</varname></term>
 316
 317         <listitem><para>Sets manager environment variables passed to
 318         all executed processes. Takes a space-separated list of
 319         variable assignments. See
 320         <citerefentry project='man-pages'><refentrytitle>environ</refentrytitle><manvolnum>7</manvolnum></citerefentry>
 321         for details about environment variables.</para>
 322
 323         <para>Example:
 324
 325         <programlisting>DefaultEnvironment="VAR1=word1 word2" VAR2=word3 "VAR3=word 5 6"</programlisting>
 326
 327         Sets three variables
 328         <literal>VAR1</literal>,
 329         <literal>VAR2</literal>,
 330         <literal>VAR3</literal>.</para></listitem>
 331       </varlistentry>
 332
 333       <varlistentry>
 334         <term><varname>DefaultCPUAccounting=</varname></term>
 335         <term><varname>DefaultBlockIOAccounting=</varname></term>
 336         <term><varname>DefaultMemoryAccounting=</varname></term>
 337         <term><varname>DefaultTasksAccounting=</varname></term>
 338         <term><varname>DefaultIPAccounting=</varname></term>
 339
 340         <listitem><para>Configure the default resource accounting settings, as configured per-unit by
 341         <varname>CPUAccounting=</varname>, <varname>BlockIOAccounting=</varname>, <varname>MemoryAccounting=</varname>,
 342         <varname>TasksAccounting=</varname> and <varname>IPAccounting=</varname>. See
 343         <citerefentry><refentrytitle>systemd.resource-control</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 344         for details on the per-unit settings. <varname>DefaultTasksAccounting=</varname> defaults to on,
 345         <varname>DefaultMemoryAccounting=</varname> to &MEMORY_ACCOUNTING_DEFAULT;,
 346         the other three settings to off.</para></listitem>
 347       </varlistentry>
 348
 349       <varlistentry>
 350         <term><varname>DefaultTasksMax=</varname></term>
 351
 352         <listitem><para>Configure the default value for the per-unit <varname>TasksMax=</varname> setting. See
 353         <citerefentry><refentrytitle>systemd.resource-control</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 354         for details. This setting applies to all unit types that support resource control settings, with the exception
 355         of slice units. Defaults to 15%, which equals 4915 with the kernel's defaults on the host, but might be smaller
 356         in OS containers.</para></listitem>
 357       </varlistentry>
 358
 359       <varlistentry>
 360         <term><varname>DefaultLimitCPU=</varname></term>
 361         <term><varname>DefaultLimitFSIZE=</varname></term>
 362         <term><varname>DefaultLimitDATA=</varname></term>
 363         <term><varname>DefaultLimitSTACK=</varname></term>
 364         <term><varname>DefaultLimitCORE=</varname></term>
 365         <term><varname>DefaultLimitRSS=</varname></term>
 366         <term><varname>DefaultLimitNOFILE=</varname></term>
 367         <term><varname>DefaultLimitAS=</varname></term>
 368         <term><varname>DefaultLimitNPROC=</varname></term>
 369         <term><varname>DefaultLimitMEMLOCK=</varname></term>
 370         <term><varname>DefaultLimitLOCKS=</varname></term>
 371         <term><varname>DefaultLimitSIGPENDING=</varname></term>
 372         <term><varname>DefaultLimitMSGQUEUE=</varname></term>
 373         <term><varname>DefaultLimitNICE=</varname></term>
 374         <term><varname>DefaultLimitRTPRIO=</varname></term>
 375         <term><varname>DefaultLimitRTTIME=</varname></term>
 376
 377         <listitem><para>These settings control various default
 378         resource limits for units. See
 379         <citerefentry><refentrytitle>setrlimit</refentrytitle><manvolnum>2</manvolnum></citerefentry>
 380         for details. The resource limit is possible to specify in two formats,
 381         <option>value</option> to set soft and hard limits to the same value,
 382         or <option>soft:hard</option> to set both limits individually (e.g. DefaultLimitAS=4G:16G).
 383         Use the string <varname>infinity</varname> to
 384         configure no limit on a specific resource. The multiplicative
 385         suffixes K (=1024), M (=1024*1024) and so on for G, T, P and E
 386         may be used for resource limits measured in bytes
 387         (e.g. DefaultLimitAS=16G). For the limits referring to time values,
 388         the usual time units ms, s, min, h and so on may be used (see
 389         <citerefentry><refentrytitle>systemd.time</refentrytitle><manvolnum>7</manvolnum></citerefentry>
 390         for details). Note that if no time unit is specified for
 391         <varname>DefaultLimitCPU=</varname> the default unit of seconds is
 392         implied, while for <varname>DefaultLimitRTTIME=</varname> the default
 393         unit of microseconds is implied. Also, note that the effective
 394         granularity of the limits might influence their
 395         enforcement. For example, time limits specified for
 396         <varname>DefaultLimitCPU=</varname> will be rounded up implicitly to
 397         multiples of 1s. These  settings may be overridden in individual units
 398         using the corresponding LimitXXX= directives. Note that these resource
 399         limits are only defaults for units, they are not applied to PID 1
 400         itself.</para></listitem>
 401       </varlistentry>
 402     </variablelist>
 403   </refsect1>
 404
 405   <refsect1>
 406       <title>See Also</title>
 407       <para>
 408         <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 409         <citerefentry><refentrytitle>systemd.directives</refentrytitle><manvolnum>7</manvolnum></citerefentry>,
 410         <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
 411         <citerefentry><refentrytitle>systemd.service</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
 412         <citerefentry project='man-pages'><refentrytitle>environ</refentrytitle><manvolnum>7</manvolnum></citerefentry>,
 413         <citerefentry project='man-pages'><refentrytitle>capabilities</refentrytitle><manvolnum>7</manvolnum></citerefentry>
 414       </para>
 415   </refsect1>
 416
 417 </refentry>