nginx crash on reload -- how to detect?

[Jan-Philip Gehrcke]

Hello,

I'm currently running a self-built nginx 1.3.14 on a debian system and 
use the attached (and also inlined) init.d script as /etc/init.d/nginx 
for managing the service. It's taken unmodified from debian wheezy.

I somehow managed to get the nginx master process crashing (I have a few 
third-party modules compiled in and that's not the issue to be discussed 
right now) upon

$ service nginx reload

The problem is that in this case it just states "Reloading nginx 
configuration: nginx." without me realizing that the master process 
crashed and that the new config did not become activated. This is an 
issue by itself -- I spent some time changing the config over and over 
and doing reload attempts and was wondering why the heck the changes did 
not take effect.

Another

$ service nginx stop
$ service nginx start

then revealed that something wrong is going on, because 'stop' did not 
take action, 'start' spawned a new master process, but the listening 
ports were still blocked by old workers.

I am wondering if there is a neat way to improve the service script in 
order to make it realize when the nginx master unexpectedly dies in the 
process of performing one of the service actions.

Cheers,

Jan-Philip



#!/bin/sh

### BEGIN INIT INFO
# Provides:          nginx
# Required-Start:    $local_fs $remote_fs $network $syslog
# Required-Stop:     $local_fs $remote_fs $network $syslog
# Default-Start:     2 3 4 5
# Default-Stop:      0 1 6
# Short-Description: starts the nginx web server
# Description:       starts nginx using start-stop-daemon
### END INIT INFO

PATH=/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin
DAEMON=/usr/sbin/nginx
NAME=nginx
DESC=nginx

# Include nginx defaults if available
if [ -f /etc/default/nginx ]; then
	. /etc/default/nginx
fi

test -x $DAEMON || exit 0

set -e

. /lib/lsb/init-functions

test_nginx_config() {
	if $DAEMON -t $DAEMON_OPTS >/dev/null 2>&1; then
		return 0
	else
		$DAEMON -t $DAEMON_OPTS
		return $?
	fi
}

case "$1" in
	start)
		echo -n "Starting $DESC: "
		test_nginx_config
		# Check if the ULIMIT is set in /etc/default/nginx
		if [ -n "$ULIMIT" ]; then
			# Set the ulimits
			ulimit $ULIMIT
		fi
		start-stop-daemon --start --quiet --pidfile /var/run/$NAME.pid \
		    --exec $DAEMON -- $DAEMON_OPTS || true
		echo "$NAME."
		;;

	stop)
		echo -n "Stopping $DESC: "
		start-stop-daemon --stop --quiet --pidfile /var/run/$NAME.pid \
		    --exec $DAEMON || true
		echo "$NAME."
		;;

	restart|force-reload)
		echo -n "Restarting $DESC: "
		start-stop-daemon --stop --quiet --pidfile \
		    /var/run/$NAME.pid --exec $DAEMON || true
		sleep 1
		test_nginx_config
		# Check if the ULIMIT is set in /etc/default/nginx
		if [ -n "$ULIMIT" ]; then
			# Set the ulimits
			ulimit $ULIMIT
		fi
		start-stop-daemon --start --quiet --pidfile \
		    /var/run/$NAME.pid --exec $DAEMON -- $DAEMON_OPTS || true
		echo "$NAME."
		;;

	reload)
		echo -n "Reloading $DESC configuration: "
		test_nginx_config
		start-stop-daemon --stop --signal HUP --quiet --pidfile 
/var/run/$NAME.pid \
		    --exec $DAEMON || true
		echo "$NAME."
		;;

	configtest|testconfig)
		echo -n "Testing $DESC configuration: "
		if test_nginx_config; then
			echo "$NAME."
		else
			exit $?
		fi
		;;

	status)
		status_of_proc -p /var/run/$NAME.pid "$DAEMON" nginx && exit 0 || exit $?
		;;
	*)
		echo "Usage: $NAME 
{start|stop|restart|reload|force-reload|status|configtest}" >&2
		exit 1
		;;
esac

exit 0
-------------- next part --------------
#!/bin/sh

### BEGIN INIT INFO
# Provides:          nginx
# Required-Start:    $local_fs $remote_fs $network $syslog
# Required-Stop:     $local_fs $remote_fs $network $syslog
# Default-Start:     2 3 4 5
# Default-Stop:      0 1 6
# Short-Description: starts the nginx web server
# Description:       starts nginx using start-stop-daemon
### END INIT INFO

PATH=/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin
DAEMON=/usr/sbin/nginx
NAME=nginx
DESC=nginx

# Include nginx defaults if available
if [ -f /etc/default/nginx ]; then
	. /etc/default/nginx
fi

test -x $DAEMON || exit 0

set -e

. /lib/lsb/init-functions

test_nginx_config() {
	if $DAEMON -t $DAEMON_OPTS >/dev/null 2>&1; then
		return 0
	else
		$DAEMON -t $DAEMON_OPTS
		return $?
	fi
}

case "$1" in
	start)
		echo -n "Starting $DESC: "
		test_nginx_config
		# Check if the ULIMIT is set in /etc/default/nginx
		if [ -n "$ULIMIT" ]; then
			# Set the ulimits
			ulimit $ULIMIT
		fi
		start-stop-daemon --start --quiet --pidfile /var/run/$NAME.pid \
		    --exec $DAEMON -- $DAEMON_OPTS || true
		echo "$NAME."
		;;

	stop)
		echo -n "Stopping $DESC: "
		start-stop-daemon --stop --quiet --pidfile /var/run/$NAME.pid \
		    --exec $DAEMON || true
		echo "$NAME."
		;;

	restart|force-reload)
		echo -n "Restarting $DESC: "
		start-stop-daemon --stop --quiet --pidfile \
		    /var/run/$NAME.pid --exec $DAEMON || true
		sleep 1
		test_nginx_config
		# Check if the ULIMIT is set in /etc/default/nginx
		if [ -n "$ULIMIT" ]; then
			# Set the ulimits
			ulimit $ULIMIT
		fi
		start-stop-daemon --start --quiet --pidfile \
		    /var/run/$NAME.pid --exec $DAEMON -- $DAEMON_OPTS || true
		echo "$NAME."
		;;

	reload)
		echo -n "Reloading $DESC configuration: "
		test_nginx_config
		start-stop-daemon --stop --signal HUP --quiet --pidfile /var/run/$NAME.pid \
		    --exec $DAEMON || true
		echo "$NAME."
		;;

	configtest|testconfig)
		echo -n "Testing $DESC configuration: "
		if test_nginx_config; then
			echo "$NAME."
		else
			exit $?
		fi
		;;

	status)
		status_of_proc -p /var/run/$NAME.pid "$DAEMON" nginx && exit 0 || exit $?
		;;
	*)
		echo "Usage: $NAME {start|stop|restart|reload|force-reload|status|configtest}" >&2
		exit 1
		;;
esac

exit 0