Nagios Support Forum

Setting the timeout to 45 seconds didn't work. I still got a bunch of those errors a few days ago.

The server that has seen this happen the most has a total of 48 checks. Most of those checks happen every minute (was every 30 sec. but scaled back to 1 min. to try to stop this problem.) A few of the checks only happen every 5 minutes.

The other servers all have fewer checks, but still probably have at least 30.

*edit - NTP is running on these boxes, so the time should be fine.

This really does sound like a max connections issue with either port 5666 or NRPE. I cannot find anything in the NRPE documentation on the issue. Are you using some kind of firewall? Does it have some sort of setting that only allows a certain amount of connections on each i inidividual port? Or globally?