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diff --git a/man/systemd.kill.xml b/man/systemd.kill.xml new file mode 100644 index 0000000..91de22f --- /dev/null +++ b/man/systemd.kill.xml @@ -0,0 +1,195 @@ +<?xml version='1.0'?> <!--*-nxml-*--> +<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN" + "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd"> +<!-- SPDX-License-Identifier: LGPL-2.1-or-later --> + +<refentry id="systemd.kill"> + <refentryinfo> + <title>systemd.kill</title> + <productname>systemd</productname> + </refentryinfo> + + <refmeta> + <refentrytitle>systemd.kill</refentrytitle> + <manvolnum>5</manvolnum> + </refmeta> + + <refnamediv> + <refname>systemd.kill</refname> + <refpurpose>Process killing procedure + configuration</refpurpose> + </refnamediv> + + <refsynopsisdiv> + <para><filename><replaceable>service</replaceable>.service</filename>, + <filename><replaceable>socket</replaceable>.socket</filename>, + <filename><replaceable>mount</replaceable>.mount</filename>, + <filename><replaceable>swap</replaceable>.swap</filename>, + <filename><replaceable>scope</replaceable>.scope</filename></para> + </refsynopsisdiv> + + <refsect1> + <title>Description</title> + + <para>Unit configuration files for services, sockets, mount + points, swap devices and scopes share a subset of configuration + options which define the killing procedure of processes belonging + to the unit.</para> + + <para>This man page lists the configuration options shared by + these five unit types. See + <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry> + for the common options shared by all unit configuration files, and + <citerefentry><refentrytitle>systemd.service</refentrytitle><manvolnum>5</manvolnum></citerefentry>, + <citerefentry><refentrytitle>systemd.socket</refentrytitle><manvolnum>5</manvolnum></citerefentry>, + <citerefentry><refentrytitle>systemd.swap</refentrytitle><manvolnum>5</manvolnum></citerefentry>, + <citerefentry><refentrytitle>systemd.mount</refentrytitle><manvolnum>5</manvolnum></citerefentry> + and + <citerefentry><refentrytitle>systemd.scope</refentrytitle><manvolnum>5</manvolnum></citerefentry> + for more information on the configuration file options specific to + each unit type.</para> + + <para>The kill procedure configuration options are configured in + the [Service], [Socket], [Mount] or [Swap] section, depending on + the unit type.</para> + </refsect1> + + <refsect1> + <title>Options</title> + + <variablelist class='unit-directives'> + + <varlistentry> + <term><varname>KillMode=</varname></term> + <listitem><para>Specifies how processes of this unit shall be killed. One of + <option>control-group</option>, <option>mixed</option>, <option>process</option>, + <option>none</option>.</para> + + <para>If set to <option>control-group</option>, all remaining processes in the control group of this + unit will be killed on unit stop (for services: after the stop command is executed, as configured + with <varname>ExecStop=</varname>). If set to <option>mixed</option>, the + <constant>SIGTERM</constant> signal (see below) is sent to the main process while the subsequent + <constant>SIGKILL</constant> signal (see below) is sent to all remaining processes of the unit's + control group. If set to <option>process</option>, only the main process itself is killed (not + recommended!). If set to <option>none</option>, no process is killed (strongly recommended + against!). In this case, only the stop command will be executed on unit stop, but no process will be + killed otherwise. Processes remaining alive after stop are left in their control group and the + control group continues to exist after stop unless empty.</para> + + <para>Note that it is not recommended to set <varname>KillMode=</varname> to + <constant>process</constant> or even <constant>none</constant>, as this allows processes to escape + the service manager's lifecycle and resource management, and to remain running even while their + service is considered stopped and is assumed to not consume any resources.</para> + + <para>Processes will first be terminated via <constant>SIGTERM</constant> (unless the signal to send + is changed via <varname>KillSignal=</varname> or <varname>RestartKillSignal=</varname>). Optionally, + this is immediately followed by a <constant>SIGHUP</constant> (if enabled with + <varname>SendSIGHUP=</varname>). If processes still remain after: + <itemizedlist> + <listitem><para>the main process of a unit has exited (applies to <varname>KillMode=</varname>: + <option>mixed</option>)</para></listitem> + <listitem><para>the delay configured via the <varname>TimeoutStopSec=</varname> has passed + (applies to <varname>KillMode=</varname>: <option>control-group</option>, <option>mixed</option>, + <option>process</option>)</para></listitem> + </itemizedlist> + + the termination request is repeated with the <constant>SIGKILL</constant> signal or the signal specified via + <varname>FinalKillSignal=</varname> (unless this is disabled via the <varname>SendSIGKILL=</varname> + option). See <citerefentry><refentrytitle>kill</refentrytitle><manvolnum>2</manvolnum></citerefentry> + for more information.</para> + + <para>Defaults to <option>control-group</option>.</para></listitem> + </varlistentry> + + <varlistentry> + <term><varname>KillSignal=</varname></term> + <listitem><para>Specifies which signal to use when stopping a service. This controls the signal that + is sent as first step of shutting down a unit (see above), and is usually followed by + <constant>SIGKILL</constant> (see above and below). For a list of valid signals, see + <citerefentry project='man-pages'><refentrytitle>signal</refentrytitle><manvolnum>7</manvolnum></citerefentry>. + Defaults to <constant>SIGTERM</constant>.</para> + + <para>Note that, right after sending the signal specified in this setting, systemd will always send + <constant>SIGCONT</constant>, to ensure that even suspended tasks can be terminated cleanly.</para> + </listitem> + </varlistentry> + + <varlistentry> + <term><varname>RestartKillSignal=</varname></term> + <listitem><para>Specifies which signal to use when restarting a service. The same as + <varname>KillSignal=</varname> described above, with the exception that this setting is used in a + restart job. Not set by default, and the value of <varname>KillSignal=</varname> is used.</para> + </listitem> + </varlistentry> + + <varlistentry> + <term><varname>SendSIGHUP=</varname></term> + <listitem><para>Specifies whether to send + <constant>SIGHUP</constant> to remaining processes immediately + after sending the signal configured with + <varname>KillSignal=</varname>. This is useful to indicate to + shells and shell-like programs that their connection has been + severed. Takes a boolean value. Defaults to "no". + </para></listitem> + </varlistentry> + + <varlistentry> + <term><varname>SendSIGKILL=</varname></term> + <listitem><para>Specifies whether to send + <constant>SIGKILL</constant> (or the signal specified by + <varname>FinalKillSignal=</varname>) to remaining processes + after a timeout, if the normal shutdown procedure left + processes of the service around. When disabled, a + <varname>KillMode=</varname> of <constant>control-group</constant> + or <constant>mixed</constant> service will not restart if + processes from prior services exist within the control group. + Takes a boolean value. Defaults to "yes". + </para></listitem> + </varlistentry> + + <varlistentry> + <term><varname>FinalKillSignal=</varname></term> + <listitem><para>Specifies which signal to send to remaining + processes after a timeout if <varname>SendSIGKILL=</varname> + is enabled. The signal configured here should be one that is + not typically caught and processed by services (<constant>SIGTERM</constant> + is not suitable). Developers can find it useful to use this to + generate a coredump to troubleshoot why a service did not + terminate upon receiving the initial <constant>SIGTERM</constant> + signal. This can be achieved by configuring <varname>LimitCORE=</varname> + and setting <varname>FinalKillSignal=</varname> to either + <constant>SIGQUIT</constant> or <constant>SIGABRT</constant>. + Defaults to <constant>SIGKILL</constant>. + </para></listitem> + </varlistentry> + + <varlistentry> + <term><varname>WatchdogSignal=</varname></term> + <listitem><para>Specifies which signal to use to terminate the + service when the watchdog timeout expires (enabled through + <varname>WatchdogSec=</varname>). Defaults to <constant>SIGABRT</constant>. + </para></listitem> + </varlistentry> + + </variablelist> + </refsect1> + + <refsect1> + <title>See Also</title> + <para> + <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>, + <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>, + <citerefentry><refentrytitle>journalctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>, + <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>, + <citerefentry><refentrytitle>systemd.service</refentrytitle><manvolnum>5</manvolnum></citerefentry>, + <citerefentry><refentrytitle>systemd.socket</refentrytitle><manvolnum>5</manvolnum></citerefentry>, + <citerefentry><refentrytitle>systemd.swap</refentrytitle><manvolnum>5</manvolnum></citerefentry>, + <citerefentry><refentrytitle>systemd.mount</refentrytitle><manvolnum>5</manvolnum></citerefentry>, + <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>, + <citerefentry><refentrytitle>systemd.directives</refentrytitle><manvolnum>7</manvolnum></citerefentry>, + <citerefentry><refentrytitle>kill</refentrytitle><manvolnum>2</manvolnum></citerefentry>, + <citerefentry project='man-pages'><refentrytitle>signal</refentrytitle><manvolnum>7</manvolnum></citerefentry> + </para> + </refsect1> + +</refentry> |