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| <!-- SPDX-License-Identifier: LGPL-2.1+ --> |
| |
| <refentry id="systemd-system.conf" |
| xmlns:xi="http://www.w3.org/2001/XInclude"> |
| <refentryinfo> |
| <title>systemd-system.conf</title> |
| <productname>systemd</productname> |
| </refentryinfo> |
| |
| <refmeta> |
| <refentrytitle>systemd-system.conf</refentrytitle> |
| <manvolnum>5</manvolnum> |
| </refmeta> |
| |
| <refnamediv> |
| <refname>systemd-system.conf</refname> |
| <refname>system.conf.d</refname> |
| <refname>systemd-user.conf</refname> |
| <refname>user.conf.d</refname> |
| <refpurpose>System and session service manager configuration files</refpurpose> |
| </refnamediv> |
| |
| <refsynopsisdiv> |
| <para><filename>/etc/systemd/system.conf</filename>, |
| <filename>/etc/systemd/system.conf.d/*.conf</filename>, |
| <filename>/run/systemd/system.conf.d/*.conf</filename>, |
| <filename>/usr/lib/systemd/system.conf.d/*.conf</filename></para> |
| <para><filename>/etc/systemd/user.conf</filename>, |
| <filename>/etc/systemd/user.conf.d/*.conf</filename>, |
| <filename>/run/systemd/user.conf.d/*.conf</filename>, |
| <filename>/usr/lib/systemd/user.conf.d/*.conf</filename></para> |
| </refsynopsisdiv> |
| |
| <refsect1> |
| <title>Description</title> |
| |
| <para>When run as a system instance, systemd interprets the |
| configuration file <filename>system.conf</filename> and the files |
| in <filename>system.conf.d</filename> directories; when run as a |
| user instance, systemd interprets the configuration file |
| <filename>user.conf</filename> and the files in |
| <filename>user.conf.d</filename> directories. These configuration |
| files contain a few settings controlling basic manager |
| operations. See |
| <citerefentry><refentrytitle>systemd.syntax</refentrytitle><manvolnum>7</manvolnum></citerefentry> |
| for a general description of the syntax.</para> |
| </refsect1> |
| |
| <xi:include href="standard-conf.xml" xpointer="main-conf" /> |
| |
| <refsect1> |
| <title>Options</title> |
| |
| <para>All options are configured in the |
| [Manager] section:</para> |
| |
| <variablelist class='config-directives'> |
| |
| <varlistentry> |
| <term><varname>LogColor=</varname></term> |
| <term><varname>LogLevel=</varname></term> |
| <term><varname>LogLocation=</varname></term> |
| <term><varname>LogTarget=</varname></term> |
| <term><varname>LogTime=</varname></term> |
| <term><varname>DumpCore=yes</varname></term> |
| <term><varname>CrashChangeVT=no</varname></term> |
| <term><varname>CrashShell=no</varname></term> |
| <term><varname>CrashReboot=no</varname></term> |
| <term><varname>ShowStatus=yes</varname></term> |
| <term><varname>DefaultStandardOutput=journal</varname></term> |
| <term><varname>DefaultStandardError=inherit</varname></term> |
| |
| <listitem><para>Configures various parameters of basic manager operation. These options may be overridden by |
| the respective process and kernel command line arguments. See |
| <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry> for |
| details.</para></listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><varname>CtrlAltDelBurstAction=</varname></term> |
| |
| <listitem><para>Defines what action will be performed |
| if user presses Ctrl-Alt-Delete more than 7 times in 2s. |
| Can be set to <literal>reboot-force</literal>, <literal>poweroff-force</literal>, |
| <literal>reboot-immediate</literal>, <literal>poweroff-immediate</literal> |
| or disabled with <literal>none</literal>. Defaults to |
| <literal>reboot-force</literal>. |
| </para></listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><varname>CPUAffinity=</varname></term> |
| |
| <listitem><para>Configures the CPU affinity for the service manager as well as the default CPU |
| affinity for all forked off processes. Takes a list of CPU indices or ranges separated by either |
| whitespace or commas. CPU ranges are specified by the lower and upper CPU indices separated by a |
| dash. This option may be specified more than once, in which case the specified CPU affinity masks are |
| merged. If the empty string is assigned, the mask is reset, all assignments prior to this will have |
| no effect. Individual services may override the CPU affinity for their processes with the |
| <varname>CPUAffinity=</varname> setting in unit files, see |
| <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para></listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><varname>NUMAPolicy=</varname></term> |
| |
| <listitem><para>Configures the NUMA memory policy for the service manager and the default NUMA memory policy |
| for all forked off processes. Individual services may override the default policy with the |
| <varname>NUMAPolicy=</varname> setting in unit files, see |
| <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para></listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><varname>NUMAMask=</varname></term> |
| |
| <listitem><para>Configures the NUMA node mask that will be associated with the selected NUMA policy. Note that |
| <option>default</option> and <option>local</option> NUMA policies don't require explicit NUMA node mask and |
| value of the option can be empty. Similarly to <varname>NUMAPolicy=</varname>, value can be overridden |
| by individual services in unit files, see |
| <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para></listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><varname>RuntimeWatchdogSec=</varname></term> |
| <term><varname>RebootWatchdogSec=</varname></term> |
| <term><varname>KExecWatchdogSec=</varname></term> |
| |
| <listitem><para>Configure the hardware watchdog at runtime and at reboot. Takes a timeout value in seconds (or |
| in other time units if suffixed with <literal>ms</literal>, <literal>min</literal>, <literal>h</literal>, |
| <literal>d</literal>, <literal>w</literal>). If <varname>RuntimeWatchdogSec=</varname> is set to a non-zero |
| value, the watchdog hardware (<filename>/dev/watchdog</filename> or the path specified with |
| <varname>WatchdogDevice=</varname> or the kernel option <varname>systemd.watchdog-device=</varname>) will be |
| programmed to automatically reboot the system if it is not contacted within the specified timeout interval. The |
| system manager will ensure to contact it at least once in half the specified timeout interval. This feature |
| requires a hardware watchdog device to be present, as it is commonly the case in embedded and server |
| systems. Not all hardware watchdogs allow configuration of all possible reboot timeout values, in which case |
| the closest available timeout is picked. <varname>RebootWatchdogSec=</varname> may be used to configure the |
| hardware watchdog when the system is asked to reboot. It works as a safety net to ensure that the reboot takes |
| place even if a clean reboot attempt times out. Note that the <varname>RebootWatchdogSec=</varname> timeout |
| applies only to the second phase of the reboot, i.e. after all regular services are already terminated, and |
| after the system and service manager process (PID 1) got replaced by the <filename>systemd-shutdown</filename> |
| binary, see system <citerefentry><refentrytitle>bootup</refentrytitle><manvolnum>7</manvolnum></citerefentry> |
| for details. During the first phase of the shutdown operation the system and service manager remains running |
| and hence <varname>RuntimeWatchdogSec=</varname> is still honoured. In order to define a timeout on this first |
| phase of system shutdown, configure <varname>JobTimeoutSec=</varname> and <varname>JobTimeoutAction=</varname> |
| in the [Unit] section of the <filename>shutdown.target</filename> unit. By default |
| <varname>RuntimeWatchdogSec=</varname> defaults to 0 (off), and <varname>RebootWatchdogSec=</varname> to |
| 10min. <varname>KExecWatchdogSec=</varname> may be used to additionally enable the watchdog when kexec |
| is being executed rather than when rebooting. Note that if the kernel does not reset the watchdog on kexec (depending |
| on the specific hardware and/or driver), in this case the watchdog might not get disabled after kexec succeeds |
| and thus the system might get rebooted, unless <varname>RuntimeWatchdogSec=</varname> is also enabled at the same time. |
| For this reason it is recommended to enable <varname>KExecWatchdogSec=</varname> only if |
| <varname>RuntimeWatchdogSec=</varname> is also enabled. |
| These settings have no effect if a hardware watchdog is not available.</para></listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><varname>WatchdogDevice=</varname></term> |
| |
| <listitem><para>Configure the hardware watchdog device that the |
| runtime and shutdown watchdog timers will open and use. Defaults |
| to <filename>/dev/watchdog</filename>. This setting has no |
| effect if a hardware watchdog is not available.</para></listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><varname>CapabilityBoundingSet=</varname></term> |
| |
| <listitem><para>Controls which capabilities to include in the |
| capability bounding set for PID 1 and its children. See |
| <citerefentry project='man-pages'><refentrytitle>capabilities</refentrytitle><manvolnum>7</manvolnum></citerefentry> |
| for details. Takes a whitespace-separated list of capability |
| names as read by |
| <citerefentry project='mankier'><refentrytitle>cap_from_name</refentrytitle><manvolnum>3</manvolnum></citerefentry>. |
| Capabilities listed will be included in the bounding set, all |
| others are removed. If the list of capabilities is prefixed |
| with ~, all but the listed capabilities will be included, the |
| effect of the assignment inverted. Note that this option also |
| affects the respective capabilities in the effective, |
| permitted and inheritable capability sets. The capability |
| bounding set may also be individually configured for units |
| using the <varname>CapabilityBoundingSet=</varname> directive |
| for units, but note that capabilities dropped for PID 1 cannot |
| be regained in individual units, they are lost for |
| good.</para></listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><varname>NoNewPrivileges=</varname></term> |
| |
| <listitem><para>Takes a boolean argument. If true, ensures that PID 1 |
| and all its children can never gain new privileges through |
| <citerefentry project='man-pages'><refentrytitle>execve</refentrytitle><manvolnum>2</manvolnum></citerefentry> |
| (e.g. via setuid or setgid bits, or filesystem capabilities). |
| Defaults to false. General purpose distributions commonly rely |
| on executables with setuid or setgid bits and will thus not |
| function properly with this option enabled. Individual units |
| cannot disable this option. |
| Also see <ulink url="https://www.kernel.org/doc/html/latest/userspace-api/no_new_privs.html">No New Privileges Flag</ulink>. |
| </para></listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><varname>SystemCallArchitectures=</varname></term> |
| |
| <listitem><para>Takes a space-separated list of architecture |
| identifiers. Selects from which architectures system calls may |
| be invoked on this system. This may be used as an effective |
| way to disable invocation of non-native binaries system-wide, |
| for example to prohibit execution of 32-bit x86 binaries on |
| 64-bit x86-64 systems. This option operates system-wide, and |
| acts similar to the |
| <varname>SystemCallArchitectures=</varname> setting of unit |
| files, see |
| <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry> |
| for details. This setting defaults to the empty list, in which |
| case no filtering of system calls based on architecture is |
| applied. Known architecture identifiers are |
| <literal>x86</literal>, <literal>x86-64</literal>, |
| <literal>x32</literal>, <literal>arm</literal> and the special |
| identifier <literal>native</literal>. The latter implicitly |
| maps to the native architecture of the system (or more |
| specifically, the architecture the system manager was compiled |
| for). Set this setting to <literal>native</literal> to |
| prohibit execution of any non-native binaries. When a binary |
| executes a system call of an architecture that is not listed |
| in this setting, it will be immediately terminated with the |
| SIGSYS signal.</para></listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><varname>TimerSlackNSec=</varname></term> |
| |
| <listitem><para>Sets the timer slack in nanoseconds for PID 1, |
| which is inherited by all executed processes, unless |
| overridden individually, for example with the |
| <varname>TimerSlackNSec=</varname> setting in service units |
| (for details see |
| <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>). |
| The timer slack controls the accuracy of wake-ups triggered by |
| system timers. See |
| <citerefentry><refentrytitle>prctl</refentrytitle><manvolnum>2</manvolnum></citerefentry> |
| for more information. Note that in contrast to most other time |
| span definitions this parameter takes an integer value in |
| nano-seconds if no unit is specified. The usual time units are |
| understood too.</para></listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><varname>StatusUnitFormat=</varname></term> |
| |
| <listitem><para>Takes either <option>name</option> or <option>description</option> as the value. If |
| <option>name</option>, the system manager will use unit names in status messages, instead of the |
| longer and more informative descriptions set with <varname>Description=</varname>, see |
| <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>. |
| </para></listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><varname>DefaultTimerAccuracySec=</varname></term> |
| |
| <listitem><para>Sets the default accuracy of timer units. This |
| controls the global default for the |
| <varname>AccuracySec=</varname> setting of timer units, see |
| <citerefentry><refentrytitle>systemd.timer</refentrytitle><manvolnum>5</manvolnum></citerefentry> |
| for details. <varname>AccuracySec=</varname> set in individual |
| units override the global default for the specific unit. |
| Defaults to 1min. Note that the accuracy of timer units is |
| also affected by the configured timer slack for PID 1, see |
| <varname>TimerSlackNSec=</varname> above.</para></listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><varname>DefaultTimeoutStartSec=</varname></term> |
| <term><varname>DefaultTimeoutStopSec=</varname></term> |
| <term><varname>DefaultTimeoutAbortSec=</varname></term> |
| <term><varname>DefaultRestartSec=</varname></term> |
| |
| <listitem><para>Configures the default timeouts for starting, |
| stopping and aborting of units, as well as the default time to sleep |
| between automatic restarts of units, as configured per-unit in |
| <varname>TimeoutStartSec=</varname>, |
| <varname>TimeoutStopSec=</varname>, |
| <varname>TimeoutAbortSec=</varname> and |
| <varname>RestartSec=</varname> (for services, see |
| <citerefentry><refentrytitle>systemd.service</refentrytitle><manvolnum>5</manvolnum></citerefentry> |
| for details on the per-unit settings). Disabled by default, when |
| service with <varname>Type=oneshot</varname> is used. |
| For non-service units, |
| <varname>DefaultTimeoutStartSec=</varname> sets the default |
| <varname>TimeoutSec=</varname> |
| value. <varname>DefaultTimeoutStartSec=</varname> and |
| <varname>DefaultTimeoutStopSec=</varname> default to |
| 90s. <varname>DefaultTimeoutAbortSec=</varname> is not set by default |
| so that all units fall back to <varname>TimeoutStopSec=</varname>. |
| <varname>DefaultRestartSec=</varname> defaults to |
| 100ms.</para></listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><varname>DefaultStartLimitIntervalSec=</varname></term> |
| <term><varname>DefaultStartLimitBurst=</varname></term> |
| |
| <listitem><para>Configure the default unit start rate |
| limiting, as configured per-service by |
| <varname>StartLimitIntervalSec=</varname> and |
| <varname>StartLimitBurst=</varname>. See |
| <citerefentry><refentrytitle>systemd.service</refentrytitle><manvolnum>5</manvolnum></citerefentry> |
| for details on the per-service settings. |
| <varname>DefaultStartLimitIntervalSec=</varname> defaults to |
| 10s. <varname>DefaultStartLimitBurst=</varname> defaults to |
| 5.</para></listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><varname>DefaultEnvironment=</varname></term> |
| |
| <listitem><para>Sets manager environment variables passed to |
| all executed processes. Takes a space-separated list of |
| variable assignments. See |
| <citerefentry project='man-pages'><refentrytitle>environ</refentrytitle><manvolnum>7</manvolnum></citerefentry> |
| for details about environment variables.</para> |
| |
| <para>Example: |
| |
| <programlisting>DefaultEnvironment="VAR1=word1 word2" VAR2=word3 "VAR3=word 5 6"</programlisting> |
| |
| Sets three variables |
| <literal>VAR1</literal>, |
| <literal>VAR2</literal>, |
| <literal>VAR3</literal>.</para></listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><varname>DefaultCPUAccounting=</varname></term> |
| <term><varname>DefaultBlockIOAccounting=</varname></term> |
| <term><varname>DefaultMemoryAccounting=</varname></term> |
| <term><varname>DefaultTasksAccounting=</varname></term> |
| <term><varname>DefaultIOAccounting=</varname></term> |
| <term><varname>DefaultIPAccounting=</varname></term> |
| |
| <listitem><para>Configure the default resource accounting settings, as configured per-unit by |
| <varname>CPUAccounting=</varname>, <varname>BlockIOAccounting=</varname>, <varname>MemoryAccounting=</varname>, |
| <varname>TasksAccounting=</varname>, <varname>IOAccounting=</varname> and <varname>IPAccounting=</varname>. See |
| <citerefentry><refentrytitle>systemd.resource-control</refentrytitle><manvolnum>5</manvolnum></citerefentry> |
| for details on the per-unit settings. <varname>DefaultTasksAccounting=</varname> defaults to yes, |
| <varname>DefaultMemoryAccounting=</varname> to &MEMORY_ACCOUNTING_DEFAULT;. <varname>DefaultCPUAccounting=</varname> |
| defaults to yes if enabling CPU accounting doesn't require the CPU controller to be enabled (Linux 4.15+ using the |
| unified hierarchy for resource control), otherwise it defaults to no. The other three settings default to no.</para></listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><varname>DefaultTasksMax=</varname></term> |
| |
| <listitem><para>Configure the default value for the per-unit <varname>TasksMax=</varname> setting. See |
| <citerefentry><refentrytitle>systemd.resource-control</refentrytitle><manvolnum>5</manvolnum></citerefentry> |
| for details. This setting applies to all unit types that support resource control settings, with the exception |
| of slice units. Defaults to 15% of the sysctl setting <varname>kernel.pid_max=</varname> or root cgroup <varname>pids.max</varname>. |
| Kernel has a default value for <varname>kernel.pid_max=</varname> and an algorithm of counting in case of more than 32 cores. |
| For example with the default <varname>kernel.pid_max=</varname>, <varname>DefaultTasksMax=</varname> defaults to 4915, |
| but might be greater in other systems or smaller in OS containers.</para></listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><varname>DefaultLimitCPU=</varname></term> |
| <term><varname>DefaultLimitFSIZE=</varname></term> |
| <term><varname>DefaultLimitDATA=</varname></term> |
| <term><varname>DefaultLimitSTACK=</varname></term> |
| <term><varname>DefaultLimitCORE=</varname></term> |
| <term><varname>DefaultLimitRSS=</varname></term> |
| <term><varname>DefaultLimitNOFILE=</varname></term> |
| <term><varname>DefaultLimitAS=</varname></term> |
| <term><varname>DefaultLimitNPROC=</varname></term> |
| <term><varname>DefaultLimitMEMLOCK=</varname></term> |
| <term><varname>DefaultLimitLOCKS=</varname></term> |
| <term><varname>DefaultLimitSIGPENDING=</varname></term> |
| <term><varname>DefaultLimitMSGQUEUE=</varname></term> |
| <term><varname>DefaultLimitNICE=</varname></term> |
| <term><varname>DefaultLimitRTPRIO=</varname></term> |
| <term><varname>DefaultLimitRTTIME=</varname></term> |
| |
| <listitem><para>These settings control various default resource limits for processes executed by |
| units. See |
| <citerefentry><refentrytitle>setrlimit</refentrytitle><manvolnum>2</manvolnum></citerefentry> for |
| details. These settings may be overridden in individual units using the corresponding |
| <varname>LimitXXX=</varname> directives and they accept the same parameter syntax, |
| see <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry> |
| for details. Note that these resource limits are only defaults |
| for units, they are not applied to the service manager process (i.e. PID 1) itself.</para></listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><varname>DefaultOOMPolicy=</varname></term> |
| |
| <listitem><para>Configure the default policy for reacting to processes being killed by the Linux |
| Out-Of-Memory (OOM) killer. This may be used to pick a global default for the per-unit |
| <varname>OOMPolicy=</varname> setting. See |
| <citerefentry><refentrytitle>systemd.service</refentrytitle><manvolnum>5</manvolnum></citerefentry> |
| for details. Note that this default is not used for services that have <varname>Delegate=</varname> |
| turned on.</para></listitem> |
| </varlistentry> |
| </variablelist> |
| </refsect1> |
| |
| <refsect1> |
| <title>See Also</title> |
| <para> |
| <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>, |
| <citerefentry><refentrytitle>systemd.directives</refentrytitle><manvolnum>7</manvolnum></citerefentry>, |
| <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>, |
| <citerefentry><refentrytitle>systemd.service</refentrytitle><manvolnum>5</manvolnum></citerefentry>, |
| <citerefentry project='man-pages'><refentrytitle>environ</refentrytitle><manvolnum>7</manvolnum></citerefentry>, |
| <citerefentry project='man-pages'><refentrytitle>capabilities</refentrytitle><manvolnum>7</manvolnum></citerefentry> |
| </para> |
| </refsect1> |
| |
| </refentry> |