Exchange 2010 - 2 server CAS/HUB/MBX HA
Posted on 2011-02-15
Client has a two-server Exchange 2010 SP1 environment. Both servers has all three roles installed: Client Access, Hub and Mailbox.
The DAG works beautifully and this makes the Mailbox role highly available between the two servers.
Now, what about the Client Access roles? Any way to make the CAS highly available without implementing a CAS array?
We tried DNS round robin - that didn't work. When we take down a specific server offline for maintenance, Outlook sessions attempt and fail to connect to that specific CAS server. That would lead me to believe that a hardware load balancer would not work in this situation either.