I bought an “Eaton 3S” uninterruptible power supply (UPS) some time ago. It is supposed to support my servers with power in case of a power loss. I also wanted to get notified about those “power down” events, so I looked for an open-source software to monitor the UPS hardware. I found the “Network UPS Tools” (NUT). In this article, I describe some of the pitfalls I came across.
