nodes down...but they are actually up and running fine

pearl

We have 3 nodes in Orion NPM that we are monitoring.  They continually show down in the evening hours....no specific time during the evening.   Yet, when we check the servers, they are running fine and no events are showing up in them.   If we wait about 10min, they will report back up in NPM.   What could this be?

rob.hock

ICMP traffic is generally prioritized down with various vendors, so perhaps there is some sort of network contention at that time? Backups running? Also check your polling completion rate to make sure we're not running afoul there.