Running ZNC as a system daemon

Note: if you just want to run ZNC automatically, when server is turned on, look here instead.

To have ZNC run at boot time as a system daemon we will create a user and group to run ZNC from a configuration we created and then called at each time the system boots. All the commands are expected to run as an administrator.

• Create a new system user with accompanying group and a shell that cannot be used to login with:

sudo adduser --system --shell /sbin/nologin --comment "Account to run ZNC daemon" --user-group znc

• Make the configuration we will run at startup:

sudo -u znc /usr/bin/znc --datadir=/var/lib/znc --makeconf

• Here is the /etc/init.d/znc for Fedora-based machines:

#!/bin/sh
#
# znc - Advanced IRC Bouncer INIT script #
# description: An Advanced IRC bouncer INIT script for
# Source function library.
. /etc/rc.d/init.d/functions

exec=/usr/bin/znc
prog=znc
config=/var/lib/znc
runas=znc

lockfile=/var/lock/subsys/$prog

start() {
	[ -x $exec ] || exit 5
	echo -n $"Starting $prog: "
	# if not running, start it up here, usually something like "daemon $exec"
	daemon --user $runas "$exec -d $config >/dev/null 2>&1"
	# If you're reckless with your system, comment the line above and
	# uncomment this one below... I just don't get it why
	# daemon "$exec -r -d $config >/dev/null 2>&1"
	retval=$?
	echo
	[ $retval -eq 0 ] && touch $lockfile
	return $retval
}

stop() {
	echo -n $"Stopping $prog: "
	# stop it here, often "killproc $prog"
	killproc $prog -TERM
	retval=$?
	echo
	[ $retval -eq 0 ] && rm -f $lockfile
	return $retval
}

reload() {
	echo -n $"Reloading $prog: "
	# stop it here, often "killproc $prog"
	killproc $prog -HUP
	retval=$?
	echo
}

restart() {
	stop
	start
}

rh_status() {
	# run checks to determine if the service is running or use generic status
	status $prog
}

rh_status_q() {
	rh_status >/dev/null 2>&1
}

case "$1" in
	start)
		rh_status_q && exit 0
		$1
		;;
	stop)
		rh_status_q || exit 0
		$1
		;;
	restart)
		$1
		;;
	reload)
		rh_status_q || exit 7
		$1
		;;
	status)
		rh_status
		;;
	condrestart|try-restart)
		rh_status_q || exit 0
		restart
		;;
	*)
		echo $"Usage: $0 {start|stop|status|reload|restart|condrestart|try-restart}"
		exit 2
esac
exit $?

• Here is the /etc/init.d/znc for Debian-based machines:

#! /bin/sh
### BEGIN INIT INFO
# Provides:          znc
# Required-Start:    $remote_fs $syslog
# Required-Stop:     $remote_fs $syslog
# Default-Start:     2 3 4 5
# Default-Stop:      0 1 6
# Short-Description: ZNC IRC bouncer
# Description:       ZNC is an IRC bouncer
### END INIT INFO
 
PATH=/sbin:/usr/sbin:/bin:/usr/bin
DESC="ZNC daemon"
NAME=znc
DAEMON=/usr/bin/$NAME
DATADIR=/var/lib/znc
DAEMON_ARGS="--datadir=$DATADIR"
PIDDIR=/var/run/znc
PIDFILE=$PIDDIR/$NAME.pid
SCRIPTNAME=/etc/init.d/$NAME
USER=znc
GROUP=znc

# Exit if the package is not installed
[ -x "$DAEMON" ] || exit 0

# Read configuration variable file if it is present
[ -r /etc/default/$NAME ] && . /etc/default/$NAME

# Load the VERBOSE setting and other rcS variables
. /lib/init/vars.sh

# Define LSB log_* functions.
# Depend on lsb-base (>= 3.2-14) to ensure that this file is present
# and status_of_proc is working.
. /lib/lsb/init-functions

#
# Function that starts the daemon/service
#
do_start()
{
	# Return
	#   0 if daemon has been started
	#   1 if daemon was already running
	#   2 if daemon could not be started
	if [ ! -d $PIDDIR ]
	then
		mkdir $PIDDIR
	fi
	chown $USER:$GROUP $PIDDIR
	start-stop-daemon --start --quiet --pidfile $PIDFILE --exec $DAEMON --test --chuid $USER > /dev/null || return 1
	start-stop-daemon --start --quiet --pidfile $PIDFILE --exec $DAEMON --chuid $USER -- $DAEMON_ARGS > /dev/null || return 2
}

#
# Function that stops the daemon/service
#
do_stop()
{
	# Return
	#   0 if daemon has been stopped
	#   1 if daemon was already stopped
	#   2 if daemon could not be stopped
	#   other if a failure occurred
	start-stop-daemon --stop --quiet --retry=TERM/30/KILL/5 --pidfile $PIDFILE --name $NAME --chuid $USER
	RETVAL="$?"
	[ "$RETVAL" = 2 ] && return 2
	# Wait for children to finish too if this is a daemon that forks
	# and if the daemon is only ever run from this initscript.
	# If the above conditions are not satisfied then add some other code
	# that waits for the process to drop all resources that could be
	# needed by services started subsequently.  A last resort is to
	# sleep for some time.
	start-stop-daemon --stop --quiet --oknodo --retry=0/30/KILL/5 --exec $DAEMON --chuid $USER
	[ "$?" = 2 ] && return 2
	# Many daemons don't delete their pidfiles when they exit.
	rm -f $PIDFILE
	return "$RETVAL"
}

#
# Function that sends a SIGHUP to the daemon/service
#
do_reload() {
	start-stop-daemon --stop --signal 1 --quiet --pidfile $PIDFILE --name $NAME --chuid $USER
	return 0
}

case "$1" in
  start)
	[ "$VERBOSE" != no ] && log_daemon_msg "Starting $DESC" "$NAME"
	do_start
	case "$?" in
		0|1) [ "$VERBOSE" != no ] && log_end_msg 0 ;;
		2) [ "$VERBOSE" != no ] && log_end_msg 1 ;;
	esac
	;;
  stop)
	[ "$VERBOSE" != no ] && log_daemon_msg "Stopping $DESC" "$NAME"
	do_stop
	case "$?" in
		0|1) [ "$VERBOSE" != no ] && log_end_msg 0 ;;
		2) [ "$VERBOSE" != no ] && log_end_msg 1 ;;
	esac
	;;
  status)
	status_of_proc -p $PIDFILE "$DAEMON" "$NAME" && exit 0 || exit $?
	;;
  reload)
	log_daemon_msg "Reloading $DESC" "$NAME"
	do_reload
	log_end_msg $?
	;;
  restart)
	log_daemon_msg "Restarting $DESC" "$NAME"
	do_stop
	case "$?" in
	  0|1)
		do_start
		case "$?" in
			0) log_end_msg 0 ;;
			1) log_end_msg 1 ;; # Old process is still running
			*) log_end_msg 1 ;; # Failed to start
		esac
		;;
	  *)
		# Failed to stop
		log_end_msg 1
		;;
	esac
	;;
  *)
	echo "Usage: $SCRIPTNAME {status|start|stop|reload|restart}" >&2
	exit 3
	;;
esac

1. Give the right permissions to this file:

sudo chmod 755 /etc/init.d/znc

1. Execute:

sudo update-rc.d znc defaults

Now that all the pieces are in place you can now start the service yourself or restart the computer for the daemon to take its place.

• Start the service:

sudo service znc start

• Verify that the service is running:

sudo service znc status