Exchange 2007 to 2010 High Availability considerations
Posted on 2012-09-17
We are looking to upgrade to exchange 2010 sometime in the near future. We are currently running exchange 2007 in a CCR configuration as detailed below.
Approximately 1600 mailboxes
2 - HUB/CAS servers NLB
2 - Mailbox servers CCR
I have just started reading about all of the HA options available in exchange 2010 and have a few questions. We are looking to size this exchange installation for about 2500 users. So far the possible configurations I have thought about are either
3 server DAG each server having the following roles MBX+CAS+HUB. This configuration would require a hardware load balancer (prob 2 for some HA/failover).
3 server DAG mailbox role and 3 other servers running HUB/CAS array. This configuration could use MS NLB for the CAS array but most likely would also use 2 hardware load balancers.
Now I am quite new to exchange 2010 so I am looking for any possible flaws in my logic with these designs. Im not sure whether we would go completely virtual using VMware, purely physical, or some combination of virtual/physical.
The first solution with 3 servers and all roles seems like it would require less hardware and effort to setup since the builds would be identical but are there any issues that i am not aware of.