Well I'd start at the log file, notifications.log. I can't quite recall where the default is, but I have mine in /var/log/hobbit/.
In my log, there is an entry for every notification sent out. If you see them there, I'd look for the problem at the next likely culprit - the mail sending utility.
We've just recently been forced into supporting systems with hobbit, and I'm excited about the uses of the tool but I can't seem to make anything work.
We've got the monitoring up just fine and the alerts happen when stuff goes down, but I don't receive any emails. The only thing in my hobbit-alerts.cfg is this:
HOST=* MAIL me (at) work.com
What could I be missing?
Brian Thompson EDS - MSO Team (313)-592-7232 Detroit Diesel, Redford MI