doomclaw.de

I’m using ZNC on a Debian GNU/Linux server as irc bouncer. One thing that always bothered me was, that ZNC was not started by default when the server was restarted. This is due to the design to be started by a user. Since I don’t wanted to run it with an existing user on this server nor to add a new user which is capable of logging in to the server I’ve set up ZNC to run daemonized by a designated system user.

How?

1. Install znc as normal.

   apt-get install znc

2. Configure znc as normal with your normal user account but don’t start it at the end of the configuration.

   znc --makeconf

3. Substitute to root and create a new configuration directory for znc in /etc and move your newly created configuration to this directory. After this you can delete the /home/$USER/.znc diretory.

   mkdir /etc/znc
   mv /home/$USER/.znc/* /etc/znc/
   rm -R /home/$USER/.znc

4. Add a new systemgroup and -user for znc.

   addgroup --system znc
   adduser --system --no-create-home --ingroup znc znc

5. Set the appropriate rights for the configuration directory.

   chown -R znc:znc /etc/znc

6. Now you’ll need to create an init script for znc. You can either use the /etc/init.d/skeleton as base and rewrite it to your needs or you can take my init script and place it as znc in /etc/init.d/.

   #! /bin/sh
   ### BEGIN INIT INFO
   # Provides:          znc
   # Default-Start:     2 3 4 5
   # Default-Stop:      0 1 6
   # Short-Description: znc initscript
   # Description:       This is the init-Script for znc.
   ### END INIT INFO
   
   # Author: Henner M. Kruse
   #
   # Please remove the "Author" lines above and replace them
   # with your own name if you copy and modify this script.
   
   # Do NOT "set -e"
   
   # PATH should only include /usr/* if it runs after the mountnfs.sh script
   PATH=/sbin:/usr/sbin:/bin:/usr/bin
   DESC="znc, an advanced modular IRC bouncer"
   NAME=znc
   DAEMON=/usr/bin/$NAME
   DAEMON_ARGS="-d /etc/znc"
   PIDFILE=/var/run/$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 (>= 3.0-6) to ensure that this file is present.
   . /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
   	start-stop-daemon --start --quiet --chuid $USER:$GROUP --pidfile $PIDFILE --exec $DAEMON --test > /dev/null \
   		|| return 1
   	start-stop-daemon --start --quiet --chuid $USER:$GROUP --pidfile $PIDFILE --exec $DAEMON -- \
   		$DAEMON_ARGS \
   		|| return 2
   	# Add code here, if necessary, that waits for the process to be ready
   	# to handle requests from services started subsequently which depend
   	# on this one.  As a last resort, sleep for some time.
   }
   
   #
   # 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 --chuid $USER:$GROUP --pidfile $PIDFILE --name $NAME
   	RETVAL="$?"
   	[ "$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 --chuid $USER:$GROUP --exec $DAEMON
   	[ "$?" = 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() {
   	#
   	# If the daemon can reload its configuration without
   	# restarting (for example, when it is sent a SIGHUP),
   	# then implement that here.
   	#
   	start-stop-daemon --stop --signal 1 --quiet --pidfile $PIDFILE --chuid $USER:$GROUP --name $NAME
   	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
   	;;
     #reload|force-reload)
   	#
   	# If do_reload() is not implemented then leave this commented out
   	# and leave 'force-reload' as an alias for 'restart'.
   	#
   	#log_daemon_msg "Reloading $DESC" "$NAME"
   	#do_reload
   	#log_end_msg $?
   	#;;
     restart|force-reload)
   	#
   	# If the "reload" option is implemented then remove the
   	# 'force-reload' alias
   	#
   	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 {start|stop|restart|reload|force-reload}" >&2
   	echo "Usage: $SCRIPTNAME {start|stop|restart|force-reload}" >&2
   	exit 3
   	;;
   esac
   
   :

7. Now it’s time to run znc with this script. But first you’ll need to make it executable.

   chmod +x /etc/init.d/znc
   /etc/init.d/znc start

   You’ll be asked two questions at the first run. Just answer them and they’ll be gone the next time.

   [ ?? ] Would you like to create a new pem file? (yes/no) [yes]: yes
   [ ?? ] hostname of your shell (including the '.com' portion): domain.com

8. Now let’s just check if znc is running fine and with the correct user.

   ps -aux | grep znc

   This should produce an output like this:

   znc      26501  0.0  0.5   5864  1680 ?        Ss   10:06   0:00 /usr/bin/znc -d /etc/znc

9. If your ZNC daemon started correctly, you can tell your system to start it when your system starts with the following command

   update-rc.d znc defaults