At present we have FIM 2010 R2 installed on a Windows 2008 host. The portal is on same server as FIMService and Sharepoint 2010 is used. The AD DC is Windows 2008 R2 and Exchange 2010 is in use.
There is talk of possible software/hardware/os upgrades happening in the near future.
What I would like to know is whether we MUST upgrade our working FIM 2010 R2 implementation to FIM 2010 R2 SP1 in the following events:
1. Exchange "upgraded" 2010 -> 2013 (no o/s changes)
2. AD DCs "upgraded" from Windows 2008 R2 to Windows 2012 R2 (still Exch 2010, FIM server unchanged)
3. FIM server (FIMService + Portal) o/s upgrade from Windows 2008 -> 2012 imminent
Obviously, we only want to upgrade FIM 2010 R2 only when we are forced to.