Hi team,

I'm looking at a scenario where there are 3 Hosts with a SAN for storage and is Clustered for failover with so many other server/applications. The requirement is to have a High Available environment with Exchange 2013. Now I want to know the possibility of having 2xCAS (WNLB) and 2xMailbox Servers with DAG.

1) Want to know if this is a supported scenario, where DAG is implemented in a VMWare cluster.

2) The DAG on cluster is to ensure that even if no host failure occurs i have VM level failover. and if Host Level failover occurs I have cluster based failover.

Any guidance is much appreciated.

Thank you.
Cheers!

• Edited by Crypto_J 1 hour 43 minutes ago

For exchange 2013 I use 2x load balancing appliances (I use Barracuda (comes in both physical and virtual) or ZEN) instead of NLB because I have found them to be more stable and cheaper for the client.

PLUS if you buy a load balancer for less than a server, you can load-balance other roles on other servers as well. So you don't need licenses for windows server..

Then I install both CAS and Mailbox on both servers and create a DAG so that they replicate the database across the servers.

The load balancers are configured in a HA, so that if one appliance fails, another takes over, and clients dont notice anything and are still connected to the same exchange server.