checking filesystems

Hi,

I'm using GlusterFS on my systems and got some troubles with it. Actually, I got a situation on 2 of my servers where glusterfs crashed with a core-dump and umout my volumes.

Is there a solution, in Xymon, to monitor when a filesystem disappear from the "df" output ?

In the documentation, the DISK directive has to be followed with 2 values for "yellow" and "red" alerts. But what's happening if I don't set these ?

Sincerly,

Thomas