For several years now, we have been installing the open-source program NUT (Network UPS Tools) to monitor our UPSes and our clients UPSes to safely shut down servers during extended power outages.
With NUT we can rest assured that servers will not just have their power killed when their UPS's battery dies, but instead will be told to perform an orderly shutdown before the battery is exhausted which can prevent costly issues including file corruption.
The "N" in NUT stands for NETWORK which of course means that there is a networking aspect to it. Not only is NUT capable of monitoring UPSes via serial ports and USB ports but also via SNMP when a UPS supports it.
In addition, the networking capabilities of NUT include the ability for a NUT server to monitor a UPS and tell multiple client machines that also derive their power from the monitored UPS to shutdown prior to the NUT server itself being shut down.
Isn't this enough monitoring? Well, we always say, "...just like backups you can never have too much monitoring." So we have written several scripts for the Xymon Monitoring Server to monitor, graph and alert on the AC input voltage, AC output voltage, battery charge %, battery voltage & UPS load % of UPSes managed by a NUT server.
The scripts and the instructions on how to install and configure them with a Xymon server may be found HERE.
posted from my Nokia N900