Espere a que el servicio se cierre correctamente antes de apagar / reiniciar la máquina

¿Cómo se escribe un servicio systemd que se apaga con gracia al apagar o reiniciar la máquina? En particular, debería retrasar el apagado de la máquina hasta que salga con gracia.

Tengo un servicio que tarda 10 segundos en apagarse: /usr/local/bin/shutdowntest.sh:

#!/bin/bash

SHUTDOWN=0
SHUTDOWN_TIME=10
TRAPPED_SIGNAL=

function onexit() {
  TRAPPED_SIGNAL=$1
  SHUTDOWN=1
}

for SIGNAL in SIGINT SIGTERM SIGHUP SIGPIPE SIGALRM SIGUSR1 SIGUSR2; do
  trap "onexit $SIGNAL" $SIGNAL
done

echo >&2 "shutdowntest running"
while ((!SHUTDOWN || SHUTDOWN_TIME>0)); do
  if [[ -n "$TRAPPED_SIGNAL" ]]; then
    echo >&2 "shutdowntest received signal $TRAPPED_SIGNAL"
    TRAPPED_SIGNAL=
  elif ((SHUTDOWN)); then
    echo >&2 "shutdowntest Shutting down: $SHUTDOWN_TIME more sleeps"
    SHUTDOWN_TIME=$((SHUTDOWN_TIME-1))
    sleep 1
  else
    sleep 10
  fi
done
echo >&2 "shutdowntest Finished shutting down; quitting"

Configuré TimeoutStopSec en 15s en /etc/systemd/system/shutdowntest.service:

[Service]
ExecStart=/usr/local/bin/shutdowntest.sh
TimeoutStopSec=15

[Install]
WantedBy=multi-user.target

Cuando ejecuto sudo systemctl stop shutdowntest.service, el servicio se cierra con gracia según /var/log/syslog:

00:57:11 shutdowntest.sh[1980]: shutdowntest received signal SIGTERM
00:57:11 shutdowntest.sh[1980]: shutdowntest Shutting down: 10 more sleeps
00:57:11 systemd[1]: Stopping shutdowntest.service...
00:57:11 shutdowntest.sh[1980]: Terminated
00:57:11 shutdowntest.sh[1980]: shutdowntest Shutting down: 9 more sleeps
00:57:12 shutdowntest.sh[1980]: shutdowntest Shutting down: 8 more sleeps
00:57:13 shutdowntest.sh[1980]: shutdowntest Shutting down: 7 more sleeps
00:57:14 shutdowntest.sh[1980]: shutdowntest Shutting down: 6 more sleeps
00:57:15 shutdowntest.sh[1980]: shutdowntest Shutting down: 5 more sleeps
00:57:16 shutdowntest.sh[1980]: shutdowntest Shutting down: 4 more sleeps
00:57:17 shutdowntest.sh[1980]: shutdowntest Shutting down: 3 more sleeps
00:57:18 shutdowntest.sh[1980]: shutdowntest Shutting down: 2 more sleeps
00:57:19 shutdowntest.sh[1980]: shutdowntest Shutting down: 1 more sleeps
00:57:20 shutdowntest.sh[1980]: shutdowntest Finished shutting down; quitting
00:57:20 systemd[1]: Stopped shutdowntest.service.

Pero cuando yo sudo rebooto sudo shutdown nowla máquina, el servicio se cierra sin tiempo suficiente para salir con gracia, y / var / log / syslog finaliza solo 1 segundo más tarde.

00:59:30 shutdowntest.sh[2014]: Terminated
00:59:30 shutdowntest.sh[2014]: shutdowntest received signal SIGTERM
00:59:30 shutdowntest.sh[2014]: shutdowntest Shutting down: 10 more sleeps
00:59:30 systemd[1]: Stopping shutdowntest.service...

¿Cómo asegurar que el servicio tenga el tiempo ( TimeoutSeco TimeoutStopSec) para salir cuando la máquina se apaga o se reinicia?

El comentario de Bigon es correcto. Estaba buscando /var/log/syslog, pero esto está escrito por rsyslog.service, que systemd se detiene bastante temprano en el proceso de apagado (como lo indica el "Servicio de registro del sistema detenido" a continuación).

Después de activar el registro persistente journald lugar ( Storage=persistenten /etc/systemd/journald.confe systemctl restart systemd-journald), journalctl -b-1 -u shutdowntest.servicemuestra que mi servicio es de hecho se le da suficiente tiempo para apagar después de que el sistema está rebooted, shutdowno después de pulsar la tecla de encendido (ACPI G2 Soft Off).

journalctl -b-1 -u shutdowntest.service -u rsyslog.service -u systemd-logind
-- Logs begin at Mon 2018-03-26 18:39:12 UTC, end at Mon 2018-03-26 20:22:34 UTC. --
…
Mar 26 18:46:46 myhost systemd-logind[1202]: Power key pressed.
Mar 26 18:46:46 myhost systemd-logind[1202]: Powering Off...
Mar 26 18:46:46 myhost systemd-logind[1202]: System is powering down.
Mar 26 18:46:46 myhost shutdowntest.sh[1237]: Terminated
Mar 26 18:46:46 myhost shutdowntest.sh[1237]: shutdowntest received signal SIGTERM
Mar 26 18:46:46 myhost shutdowntest.sh[1237]: shutdowntest Shutting down: 10 more sleeps
Mar 26 18:46:46 myhost systemd[1]: Stopping shutdowntest.service...
Mar 26 18:46:46 myhost systemd[1]: Stopping Login Service...
Mar 26 18:46:46 myhost systemd[1]: Stopped Login Service.
Mar 26 18:46:46 myhost systemd[1]: Stopping System Logging Service...
Mar 26 18:46:47 myhost systemd[1]: Stopped System Logging Service.
Mar 26 18:46:47 myhost shutdowntest.sh[1237]: shutdowntest Shutting down: 9 more sleeps
Mar 26 18:46:48 myhost shutdowntest.sh[1237]: shutdowntest Shutting down: 8 more sleeps
Mar 26 18:46:49 myhost shutdowntest.sh[1237]: shutdowntest Shutting down: 7 more sleeps
Mar 26 18:46:50 myhost shutdowntest.sh[1237]: shutdowntest Shutting down: 6 more sleeps
Mar 26 18:46:51 myhost shutdowntest.sh[1237]: shutdowntest Shutting down: 5 more sleeps
Mar 26 18:46:52 myhost shutdowntest.sh[1237]: shutdowntest Shutting down: 4 more sleeps
Mar 26 18:46:53 myhost shutdowntest.sh[1237]: shutdowntest Shutting down: 3 more sleeps
Mar 26 18:46:54 myhost shutdowntest.sh[1237]: shutdowntest Shutting down: 2 more sleeps
Mar 26 18:46:55 myhost shutdowntest.sh[1237]: shutdowntest Shutting down: 1 more sleeps
Mar 26 18:46:56 myhost shutdowntest.sh[1237]: shutdowntest Finished shutting down; quitting
Mar 26 18:46:56 myhost systemd[1]: Stopped shutdowntest.service.