Cisco is a smart ass, but the device I used doesn’t require any pre configuration besides the first few steps, management IP and stuff. With it you just turn on and off the port, it actually doesn’t care if anything is connected on the other side.
BTW thank you for reminding me about this thread, I’m testing new, cheaper and smaller option for same purpose, considering that some products cost 100$+ and can handle only couple devices it only motivates me and others to find better and cheaper solutions. I’ll update as soon as I get parts to build the prototype, beforehand I can say that it’s even cheaper than POE option, under 30$ or so and can handle up to 20 devices, but this is not yet confirmed.
Oh and also consider to use 24V relay switch, 12V is not recommended any more,