I hope this isn't too clueless a question. I've been dealing mainly with Nagios .cfg files (not a lot else Nagios-related) for about 3 years now, and have just run into something that makes me wonder more about the app's methods ...
A few days ago I clicked on the "Host Problems" link in the sidebar by mistake, and saw that a monitored server was appearing as "down" on that screen ... even though I had not received any email notification from Nagios that it was down. FWIW, it was a 3Par server. Further, the only service this box was configured to have monitored was SSH ... which was green and fine.
I've been trying to figure out why this box was showing as down and the question that has come back at me is: how does Nagios check this sort of thing?
My problem is that, given there was only one service configured (and it was up) ... I don't know.
Any pointers, even RTFMs, are welcome.