Is there something i need to do to decommision Unity 5? I upgraded to Unity 7 so I turned Unity 5 off, everything has been running fine so I would like to get rid of it, anything I need to do?
No, upgrade steps in general - sounds like you bought new servers. So, I'll assume you upgraded from 5x to 7x with new servers since you asked about just "turning off" Unity 5. So, if this was in the same AD - you'd need to use GSM to move user accounts from one server to another. If you've done all that and all works well (which I believe you said it was fine), then you can just turn off the 5x server and be done with it.