My organization uses SRM to fail over Exchange 2010 LUNs in DR situations.
Currently, we have two mailbox servers in our DAG and both reside on the same two LUNs on the same SAN. If a disaster or failover happens, we make the DR LUNs on the DR SAN "live".
We're currently planning a move to Exchange 2013.
With the following setup, is SRM even relevant to us anymore?
- DAG setup.
- Three mailbox servers in three separate locations; on three separate SANs.
- One active mailbox database copy, two passive copies (each site will have active and passive DB copies).
With the proposed environment above, is it even necessary to have SRM in place for our Exchange LUNs?
If we had a disaster affecting a single location, Exchange would (theoretically) automatically turn the appropriate passive databases into active ones in the remaining locations. I'm sure we'd have to make sure DNS is set up correctly so that in a failover situation, Outlook clients could reach the non-failed CAS servers / mailbox servers.
I think the point of having SRM now is that the whole Exchange environment sits on a single SAN. If that SAN goes down, the DR LUNs on the other SAN can be made "live". With the proposed environment, we would have three geographically separate SANs with DAG members on each.
Do we even need SRM with a three-member Exchange 2013 DAG?