Aguarde que o serviço seja encerrado normalmente antes do desligamento / reinicialização da máquina

Question

Como você escreve um serviço systemd que normalmente é encerrado quando o computador é desligado ou reinicializado? Em particular, deve atrasar o desligamento da máquina até que saia com elegância.

Eu tenho um serviço que leva 10 segundos para desligar: /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"

Eu configurei TimeoutStopSec para 15s em /etc/systemd/system/shutdowntest.service:

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

[Install]
WantedBy=multi-user.target

Quando executo sudo systemctl stop shutdowntest.service , o serviço é encerrado normalmente de acordo com /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.

Mas quando eu sudo reboot ou sudo shutdown now da máquina, o serviço é eliminado sem tempo suficiente para sair normalmente, e o / var / log / syslog termina apenas 1s depois.

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...

Como garantir que o serviço receba o tempo ( TimeoutSec ou TimeoutStopSec ) para sair quando a máquina for desligada ou reinicializada?

    

Answer 1

O comentário do Bigon está correto. Eu estava procurando em /var/log/syslog , mas isso é escrito por rsyslog.service , que systemd pára muito cedo no processo de desligamento (como indicado por "Stopped System Logging Service" abaixo).

Depois que eu habilitei o log journaling persistente ( Storage=persistent in /etc/systemd/journald.conf e systemctl restart systemd-journald ), journalctl -b-1 -u shutdowntest.service mostra que meu serviço realmente tem tempo suficiente para desligar depois que o sistema é reboot ed, shutdown , ou após a tecla Power ser pressionada (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.