Having replaced the battery in my servers UPS, I finally decided to really look into managing it via Linux. So I spend a good evening reading the NUT documentation, and ploughing my way through the config files.
After a couple of hours, I was very proud of my little self. I had everything configured the way I liked it, and testing was a charm. I even managed to create my own scripts to run via the upssched tool, to send me email alerts at various stages of the power outage to shutdown journey.
Showed SWMBO the mails coming through on my phone, and commented that if were away, we'd still know if there's a power cut. Still chuffed, you can imagine the scene when she said
"Oh, can you still get onto the internet if there's a power failure ?"
Given that the router and modem are NOT powered via the UPS, this is a damn good point ! I think my face must have looked a little like Wile E Coyote, when he runs off a cliff and just realises.
Anyway, lack of internet during a shutdown is not a big deal - certainly not worth all the cabling I'd have to do to move the modem and router.
On a more serious note, my desire was to keep the machine on for 10 minutes, just in case the power pings back, otherwise go into a shutdown (*including* shutting the UPS itself off - something I didn't realise had to be done to save the battery). However the various guides seem to strongly recommend only shutting down when the UPS battery itself is low. Now my battery is a YUASA NPW45 and it says "45W/Cell 10 minutes". Given my server load (according to the UPS monitor) is about 15%, how long would the battery keep it going ? It's only a little thing, so I wouldn't want to push it.
Curious to hear what others think.