Ok here is a question. I have installed Exchange on 2 server to use DAG.. Fine this covers failover for the Database. However this does't provide failover for CAS. I investigated it and found that you need to use NLB to provide Failover for CAS. ok Understand. So this is how i see it...
SRV1 - HUB, DAG AND CAS
SRV2 - HUB, DAG AND CAS
SRV3 - NLB FAILOVER FOR CAS And HUB for SRV1 AND SRV2
So how would I failover SRV3? I have access to SRV4 could this be used as a failover for SRV3 and if so how do you setup nlb for this... SRV3 and SRV4 are DC with DNS on