mirror of
https://github.com/systemd/systemd.git
synced 2024-11-24 02:33:36 +08:00
189 lines
9.9 KiB
XML
189 lines
9.9 KiB
XML
<?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 the main process of a unit has
|
|
exited or the delay configured via the <varname>TimeoutStopSec=</varname> has passed, 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>
|