|
NAME | SYNOPSIS | DESCRIPTION | OPTIONS | SEE ALSO | COLOPHON |
SYSTEMD.KILL(5) systemd.kill SYSTEMD.KILL(5)
systemd.kill - Process killing procedure configuration
service.service, socket.socket, mount.mount, swap.swap, scope.scope
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.
This man page lists the configuration options shared by these five
unit types. See systemd.unit(5) for the common options shared by all
unit configuration files, and systemd.service(5), systemd.socket(5),
systemd.swap(5), systemd.mount(5) and systemd.scope(5) for more
information on the configuration file options specific to each unit
type.
The kill procedure configuration options are configured in the
[Service], [Socket], [Mount] or [Swap] section, depending on the unit
type.
KillMode=
Specifies how processes of this unit shall be killed. One of
control-group, mixed, process, none.
If set to control-group, 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
ExecStop=). If set to mixed, the SIGTERM signal (see below) is
sent to the main process while the subsequent SIGKILL signal (see
below) is sent to all remaining processes of the unit's control
group. If set to process, only the main process itself is killed
(not recommended!). If set to none, 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.
Note that it is not recommended to set KillMode= to process or
even none, 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.
Processes will first be terminated via SIGTERM (unless the signal
to send is changed via KillSignal= or RestartKillSignal=).
Optionally, this is immediately followed by a SIGHUP (if enabled
with SendSIGHUP=). If processes still remain after the main
process of a unit has exited or the delay configured via the
TimeoutStopSec= has passed, the termination request is repeated
with the SIGKILL signal or the signal specified via
FinalKillSignal= (unless this is disabled via the SendSIGKILL=
option). See kill(2) for more information.
Defaults to control-group.
KillSignal=
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 SIGKILL (see above
and below). For a list of valid signals, see signal(7). Defaults
to SIGTERM.
Note that, right after sending the signal specified in this
setting, systemd will always send SIGCONT, to ensure that even
suspended tasks can be terminated cleanly.
RestartKillSignal=
Specifies which signal to use when restarting a service. The same
as KillSignal= described above, with the exception that this
setting is used in a restart job. Not set by default, and the
value of KillSignal= is used.
SendSIGHUP=
Specifies whether to send SIGHUP to remaining processes
immediately after sending the signal configured with KillSignal=.
This is useful to indicate to shells and shell-like programs that
their connection has been severed. Takes a boolean value.
Defaults to "no".
SendSIGKILL=
Specifies whether to send SIGKILL (or the signal specified by
FinalKillSignal=) to remaining processes after a timeout, if the
normal shutdown procedure left processes of the service around.
When disabled, a KillMode= of control-group or mixed service will
not restart if processes from prior services exist within the
control group. Takes a boolean value. Defaults to "yes".
FinalKillSignal=
Specifies which signal to send to remaining processes after a
timeout if SendSIGKILL= is enabled. The signal configured here
should be one that is not typically caught and processed by
services (SIGTERM 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 SIGTERM signal. This
can be achieved by configuring LimitCORE= and setting
FinalKillSignal= to either SIGQUIT or SIGABRT. Defaults to
SIGKILL.
WatchdogSignal=
Specifies which signal to use to terminate the service when the
watchdog timeout expires (enabled through WatchdogSec=). Defaults
to SIGABRT.
systemd(1), systemctl(1), journalctl(1), systemd.unit(5),
systemd.service(5), systemd.socket(5), systemd.swap(5),
systemd.mount(5), systemd.exec(5), systemd.directives(7), kill(2),
signal(7)
This page is part of the systemd (systemd system and service manager)
project. Information about the project can be found at
⟨http://www.freedesktop.org/wiki/Software/systemd⟩. If you have a bug
report for this manual page, see
⟨http://www.freedesktop.org/wiki/Software/systemd/#bugreports⟩. This
page was obtained from the project's upstream Git repository
⟨https://github.com/systemd/systemd.git⟩ on 2020-08-13. (At that
time, the date of the most recent commit that was found in the repos‐
itory was 2020-08-11.) If you discover any rendering problems in
this HTML version of the page, or you believe there is a better or
more up-to-date source for the page, or you have corrections or
improvements to the information in this COLOPHON (which is not part
of the original manual page), send a mail to man-pages@man7.org
systemd 246 SYSTEMD.KILL(5)
Pages that refer to this page: systemd-run(1) , systemd.exec(5) , systemd.mount(5) , systemd.scope(5) , systemd.service(5) , systemd.socket(5) , systemd.swap(5) , 30-systemd-environment-d-generator(7) , systemd.directives(7) , systemd.index(7)