NAME

       systemd.kill - Process killing procedure configuration

SYNOPSIS

       service.service, socket.socket, mount.mount, swap.swap, scope.scope

DESCRIPTION

       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.

OPTIONS

       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 (applies to KillMode=: mixed)

           •   the delay configured via the TimeoutStopSec= has passed (applies to KillMode=:
               control-group, mixed, process)

           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.

           Added in version 187.

       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.

           Added in version 187.

       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.

           Added in version 244.

       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".

           Added in version 207.

       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".

           Added in version 187.

       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.

           Added in version 240.

       WatchdogSignal=
           Specifies which signal to use to terminate the service when the watchdog timeout
           expires (enabled through WatchdogSec=). Defaults to SIGABRT.

           Added in version 240.

SEE ALSO

       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)