I love good free software. apcupsd is one such item.

Even though our APC Smart-UPS 3000 RM XL came with the “Business Edition Basic” of APC’s PowerChute application, I wanted something a little more flexible - and, if possible, free. After a few minutes of searching, I came across apcupsd. I think I found some other open source project that would work for an UPS, but we only use APC anyway, so this looked like it would fit the bill perfectly - and it was available at dag!

I would be sure to test it first using the safe.apccontrol script - due to a slight misconfiguation, after I started the service, the machine promptly proceeded to shutdown! (This is documented, but I didn’t read the docs first! Who does?) FYI, the cable that came with the UPS is a 940-1524C which is listed as a SIMPLE type in the config file, but defining it as SMART is what is needed:

…snip…
UPSCABLE smart
UPSTYPE apcsmart
DEVICE /dev/ttyS0
…snip…

Of course I love having web access for monitoring:

What’s great is the Master/Slave configuration so that the main instance running on our main server can send a signal to all the other servers. Also, since it’s pretty flexible, and open source, I can customize it if I need too!