Monit switches to "not monitored" state occasionally

[Johannes Bauer]

Hi list,

I have a problem with systems which run Monit at the moment: There are
multiple clients out there running daemons. These daemons (among other
things) terminate from time to time in a well-defined fashion (for
example, if the application is updated).

We rely on monit to properly restart the daemons. However I've seen
production systems lately which were unresponsive. Upon closer
inspection I was shocked to see that all monitored processes were in the
"not monitored" state:

[...]
Process 'foobar'
  status                            not monitored
  monitoring status                 not monitored
  data collected                    Fri Jan 13 12:10:00 2012

There was defniitely no manual opertor setting them into the unmonitored
state and the logs do not give any clue as to why these processes are
unmonitored. Since /root/.monit.state is a binary file, I have no chance
of finding out any meaningful information as to what the reason might be.

Is there a way to find out what caused monit to unomonitor the daemons?
We're using monit 5.1.1-1 on Debin Squeeze with pretty simple config files:

check process foobar with pidfile /var/run/foobar.pid
start program = "/etc/init.d/foobar start"
stop program = "/etc/init.d/foobar stop"

Any help is greatly appreciated,
Best regards,
Joe