What happens when the power goes out?

[dale_at_thani_apc]

This was originally posted on APC forums on 1/27/2012

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I have just setup a windows 2008 server connected to a APC Smart-UPS 2200VA USB & Serial 230V. I want to get a better understanding of what happens when the power goes out.

I have connected it with a serial cable and installed power chute on the server. I can happily browse the power statistics and details of the UPS.

When the power goes out what will happen? I have set it up to run for as long as possible but I assume that when the UPS gets to 15% it will gracefully shutdown the server. Does it kill the power to the server or does it shutdown the server? This is important because when the power comes back up I want the computer to restart ( I have set the BIOS to return to previous state).

Can anyone tell me if this will happen or will it need to be turned on?

[BillP · Accepted solution]

This reply was originally posted by Bernard on APC forums on 1/27/2012

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Hello Dale,

Based on the setting that you have that is to keep the computer on as long as possible, when the UPS goes on battery and it runs until it reaches the low battery it'll send a shutdown signal to the connected server and it will be gracefully shutdown.When power returns, the UPS will cycle the power on its receptacles to wake up your connected server, make sure that you check "Enable OS Reboot" in Server Shutdown >Shutdown Settings in the agent's web interface or open Device Properties using the console then check Power Failure under Server Shutdown.