upgrading from 11.5.3 to 12.1.0 do's and dont's
I have a request from a customer to upgrade their F5 from the 11.5.3 to 12.1.0. I wanted to ask if there are any do's or dont's to ensure this goes as smoothly as possible. Is there any kind of best practice for this or is it as simple and cut and dry as it seems? Do I need to reactivate the licensing afterwards? Any and all information or guidance is very much appreciated