We are currently migrating from Unity 4.0(5) UM with Exchange 2003 and failover to Unity 5.0(1) UM with Exchange 2003 and failover.
Our existing unity servers are integrated with Call Manager 4.x and are working fine - we bought new servers for Unity 5.x and at the point to set permissions for 5.x.
My question is about permissions -
1) Can I use the same accounts currently in use for the new 5.x install/services?
2) When I run the permissions wizard, what affect will this have on the current accounts? Am I going to break something on the 4.x install using the same accounts and running the 5.x permissions wizard?
3) Would simply 4 new accounts for the 5.x install be better?
Remember, all 4 Unity servers will be on at the same time and we'll moving accounts from 4.x to 5.x using GSM & COBRA/DiRT - so I need to make sure that both will work at the same time.
You can run the permissions wizards on your network and not affect your current deployment of Unity 4.x.
You can also run the new AD Schema update and not affect your current 4.x deployment
You can also re-user your existing accounts used for unity. (unityadmin, unityinstall, etc)
Everything will work just fine. Add in the new Unity server to existing AD/Exchange infrastructure. Use Cobras and or GSM to move subscribers at your leisure.