High Availability for Solarwinds Switch Over

I have this Prod and DR encironment.

Until now, we did switch over process manually (manually switch the solarwinds app, license. etc.).

And I have license just for production environment.

By doing this manually, it takes a long downtime (approximately 4,5 hrs)

This long downtime bothered our production operator.

So, I want to minimize it.

Does anybody have any idea for this one?

I've read about Fileover Engine (FoE).

Can someone give best High Availability to use FoE on this environment?