We have a very relatively simple set up, looking for a very simple (reliable) solution:
Setup:
One Dell box with redundant power supplies running Windows 2003, plugged into two separate APC SmartUPS 1500 units (USB, no smart cards) on two separate circuits.
EDIT: The drain of the two UPS units is not even or predictable because other systems are separately attached to one or the other of them.
Solution required:
IF (UPS1 = Low) AND (UPS2 = Low) THEN: Shutdown gracefully ELSE: DO NOTHING!!
APCUPSD only allowes for one instance (and therefore one UPS) in a windows environment.
PowerChute can't do this without using APC Smart Cards which means utilizing our switch, but the switch does not have redundant power supplies, so it will only live for as long as one of the two UPS units. And no, i don't have the budget to buy two smart cards plus a switch with redundancy 😉
Thanks
Best Answer
Your current solution seems pretty reliable to me: If the UPS you're connected to reports low power you'll shut down.
Drain across the two units should be relatively even, so when one reports low they're probably both at a point where shutting down is advisable. The situation you're not covered for is if the other (non-monitored) UPS fails completely & the monitored one can't handle the extra load its attached power supply will demand (causing an instant failure or circuit trip). My guess is that's not very likely unless your server is really beefy.