Comment 3 for bug 174466

In fact, looking in to this a bit more I think there is a more serious bug in the init script. A reload appears to to remove the PID file all together causing the issue that Kevin Lamontagne also reported.

root@noc:/var/run/nagios2# /etc/init.d/nagios2 start
 * Starting nagios2 monitoring daemon nagios2 [ OK ]
root@noc:/var/run/nagios2# ls -l
total 4
-rw-r--r-- 1 nagios nagios 6 2007-12-17 12:48 nagios2.pid

root@noc:/var/run/nagios2# /etc/init.d/nagios2 reload
 * Reloading nagios2 monitoring daemon configuration files nagios2 [ OK ]
root@noc:/var/run/nagios2# ls -l nagios2.pid
ls: nagios2.pid: No such file or directory

Note that a reload has removed the nagios2.pid file but the nagios2 process is still running.

If you then try another reload, the init script can't find the nagios2.pid file so assumes it's not running but a ps says otherwise:

root@noc:/var/run/nagios2# /etc/init.d/nagios2 reload
 * Reloading nagios2 monitoring daemon configuration files nagios2 * Not running.
                                                                         [fail]
root@noc:/var/run/nagios2# ls -l nagios2.pid
ls: nagios2.pid: No such file or directory
root@noc:/var/run/nagios2# ps aux | grep nagios
nagios 19207 0.1 0.1 23628 2124 ? SNsl 12:50 0:00 /usr/sbin/nagios2 -d /etc/nagios2/nagios.cfg

Now there are two scenarios. Firstly, if you didn't check with ps and assumed the init script is correct (i..e nagios2 isn't running when it actually is) and start nagios2, you end up with two nagios2 processes running. Or if you try to first run "/etc/init.d/nagios2 stop" this won't kill the process because there's no PID file (remember it was removed by "/etc/init.d/nagios2 reload") and then assume it has been stopped and start it again, you once again end up with two nagios2 processes running.

root@noc:/var/run/nagios2# ls -l nagios2.pid
ls: nagios2.pid: No such file or directory
root@noc:/var/run/nagios2# /etc/init.d/nagios2 stop
 * Stopping nagios2 monitoring daemon nagios2 [ OK ]
root@noc:/var/run/nagios2# ps aux | grep nagios2
nagios 19207 0.0 0.6 28688 8116 ? SNsl 12:50 0:00 /usr/sbin/nagios2 -d /etc/nagios2/nagios.cfg
root@noc:/var/run/nagios2# /etc/init.d/nagios2 start
 * Starting nagios2 monitoring daemon nagios2 [ OK ]
root@noc:/var/run/nagios2# ps aux | grep nagios
nagios 19207 0.0 0.6 28688 8116 ? SNsl 12:50 0:00 /usr/sbin/nagios2 -d /etc/nagios2/nagios.cfg
nagios 19787 1.0 0.1 22432 1636 ? SNsl 12:57 0:00 /usr/sbin/nagios2 -d /etc/nagios2/nagios.cfg
root@noc:/var/run/nagios2# cat nagios2.pid
19787
root@noc:/var/run/nagios2# /etc/init.d/nagios2 stop
 * Stopping nagios2 monitoring daemon nagios2 [ OK ]
root@noc:/var/run/nagios2# ps aux | grep nagios2
nagios 19207 0.0 0.6 28688 8116 ? SNsl 12:50 0:00 /usr/sbin/nagios2 -d /etc/nagios2/nagios.cfg

I hope this makes sense?