We had some fierce wind here today and a little after 10 this morning, the power went out. I had configured apcupsd to properly shut down the server, but I never actually tested it.
Setting up apcupsd was so straightforward, I didn’t even bother posting about it. Basically, you can install it using apt-get and configure it by editing /etc/apcupsd/apcupsd.conf. The file has a simple layout and the comments are very helpful.
When I got home from work, I powered the machine (named governor) back on, checked /var/log/syslog and was happy to find this:
Feb 25 10:14:41 governor apcupsd[2350]: Power failure. Feb 25 10:14:41 governor kernel: [1421562.103162] r8169 0000:00:0b.0: eth0: link down Feb 25 10:14:41 governor kernel: [1421562.149510] usb 1-5: USB disconnect, address 2 Feb 25 10:14:47 governor apcupsd[2350]: Running on UPS batteries. Feb 25 10:14:58 governor apcupsd[2350]: Reached run time limit on batteries. Feb 25 10:14:58 governor apcupsd[2350]: Initiating system shutdown! ... more messages from various things shutting down ...
Perfect! Oh wait — it was great that it shut down properly, but just this short part of the log tells an interesting story.
First
Feb 25 10:14:41 governor kernel: [1421562.103162] r8169 0000:00:0b.0: eth0: link down
My switch is not on a UPS, so eth0 lost its link. No biggie.
Second
Feb 25 10:14:41 governor kernel: [1421562.149510] usb 1-5: USB disconnect, address 2
The USB drive I’m using as a backup wasn’t plugged into the UPS. This is easily fixed.
Third
It powered off after only 10 seconds? That’s because I set TIMEOUT 10 in /etc/apcupsd/apcupsd.conf, thinking the value was in minutes. It says seconds right there in the helpful comments. Silly me. Fixed.
By the way, I set this timeout value on the assumption that if the power is out for more than 10 minutes, it’s probably going to be out for a while. This machine only serves two people, it is not critical that it stays up for a long as possible during a power outage.
Oh and just for reference, I check the status of the UPS with the apcaccess status command.
Also, ironically, these lines appear in the log just before the power failure:
Feb 25 08:52:26 governor apcupsd[2350]: UPS Self Test switch to battery. Feb 25 08:52:34 governor apcupsd[2350]: UPS Self Test completed: Battery OK
It passed a self-test a little more than an hour before it got a real test.
