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I have got two Ubuntu servers running off a single UPS (APC350). The master server is connected via USB and the slave communicates over Ethernet polling the UPS every 10 seconds or so. I have set up apcupsd such that when the order to shutdown comes to one, the other will shutdown too.

However since the computers are connected via a wired switchbox, I am slightly confused about what will happen in the event of power loss. Since the switchbox will lose power, communication between the servers will be lost, and the server won't know the status of the UPS. How will it know what to do?

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What is a wired switchbox? A network switch ? – Hennes Sep 7 '13 at 15:28
This was solved. I am happy for the question to be deleted. FTR I use apcupsd and have the network switch on the UPS. Now all the computers can shutdown when the power is out. Excellent. – Frank_Zafka Sep 7 '13 at 19:09
The idea is to leave these messages to find for others with similar problems. – Hennes Sep 7 '13 at 19:11
up vote 2 down vote accepted

If the slave polls the UPS every 10 seconds, it may determine that if it is unsuccessful in communicating then power has failed and so act appropriately. You'll have to check the documentation for this.

If that's not the case, there is no reason (except for capacity) you couldn't run the switch on the UPS too to maintain communication.

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Not really in a position to test this moment, but will try pulling out a few cords latter. As for running the switch box off the UPS, I did think of that, but they are power lead incompatible.... – Frank_Zafka Nov 23 '12 at 14:21
There's no reason you couldn't hack together the appropriate type of lead. My UPS has kettle-style sockets, and I easily chopped off the kettle-style plug at the other end and wired on a normal extension-lead type socket, similar to this:… - I'd stick to a single (preferably coloured) socket though, or who knows what it'll end up powering! – Graham Wager Nov 23 '12 at 14:27
Now that is just what I am looking for. Thanks. – Frank_Zafka Nov 23 '12 at 14:29

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