PR4100 - how to power down safely

I have my two PR4100s (and my LAN) plugged into a UPS so that I have time in the event of a power failure to safely power them off.

But, I don’t see Power Off as an option in the web menu, only Hibernate and Reboot. I could SSH in and use shutdown, but what I’ve found is /usr/local/modules/script/shutdown.sh, and I don’t understand what it actually does.

What does the main power button on the front of the box do? Does it only do Power On?

Thank you in advance.

Thanks. Does Hibernate actually turn the device off? I tried the power button, didn’t do anything that I could see.

I just tried Hibernate, it powered down. Thank you!