1) are sql server 2008 and sql server 2008 r 2 2 completely different products? If so what are the main differences between the 2.
2) Is SQL 2008 R2 SP1 still supported? If not what is the latest SP level, and how long has SP1 been out of support for? I appreciate there is the MS lifecycle site, but I am not to confident on this so could do with a steer on remaining support?
3) if you have a HA setup for SQL, do all your servers need to be running the same SP level for the SQL software? or can you get away with running different versions on different servers.