Due to my understanding of it, I was hesitant to use AC recovery in the case that the power goes down more than once in a short period. It could drain the UPS to the point that it might not be able to sustain enough runtime for a proper shutdown. But I'm also a bit confused about the setup here. If the server is sent a signal to shutdown due to a grid outage, who is telling it the grid was restored? The server would always detect power because of the battery backup, so I don't think AC Power Recovery would work in this case, no? I believe I have the UPS comm server (probably apcupsd) installed on the server itself, so there's no way for it to know to wake up unless from an outside source.

Maybe you have some further incite into how to make that setup work properly.

I'm brainstorming here, but would it be possible/feasible to have the Unifi Dream Machine execute a script everytime it turns on telling the server idrac to power up. I'd have to see if the UDM has that ability as well. The UDM turning on would only really happen if power was restored from an outage. Otherwise I could send a command manually once I have access to the network.