Ordering Host Groups Page on Nagios

I ended up going with pnp4nagios. Installation was a breeze and there was no additional configuration needed to get it automatically graphing trends for every service (that produces graphable data) on every host. The entire process took maybe 30 minutes.

Monitoring over a WAN is possible, but is generally not ideal. This is because if the WAN link goes down or blips all checks will fail and you are blind to what is happening in the remote location. You also have increased latency making it less useful for LAN View performance measurements. That being said if you are going this way you probably want to set up dependencies so you don't get flooded with alerts when the WAN link has issues.

The most common way I have seen communication between a monitoring system and its monitored services is to have a site-to-site VPN tunnel. Then communication is no different from the local network. Also, Nagios is often Pull based (although it doesn't have to be). So Nagios contacts the services and servers it monitors, not the other way around.

Lastly, a more ideal solution is to use a distributed monitoring setup, with Nagios one option is described in http://nagios.sourceforge.net/docs/3_0/distributed.html .