I made an 8 outlet box with relays connected to each outlet (might post a how to). That’s connected to a Pi via GPIO.

The Pi runs PiKVM, but also has a service that:

• Checks if the router can be pinged
• Checks if the internet can be pinged
• Checks if the router webUI is up

If any of those fail, it toggles the plugs for modem and router.

I run OpnSense on a 5V miniPC. I have a second one and will be setting up CARP, too.