Quote:
The homebrew NAS is a linux box. I'm not sure that the UPS shut down software will be useful at all in that case

There's open-source software called apcupsd that can shut down a Linux box from an attached APC UPS; it can even run in network client/server mode to shut down a bunch of Linux boxes. I think it might even do that for mixed Linux/Windows boxes too these days.

I have an APC Smart-UPS 750 which does the job very well, although it keeps deciding that the Cambridge supply, at 250.5V, is a bit too high and engaging trim mode (with the click of a relay).

Peter