I have installed 2 Exchange 2010 Servers (Virtual) with the following roles installed on both Servers CAS\HUB\MB. I have created a DAG and will be using an active\passive setup for that for redundancy. My understanding is that is one of the Servers fails, then the MB on the failed Server will become active on the other Server and go from being passive to being active. My FSW folder has been installed on a Member Server with the appropriate group Exchange Trusted Subsystem being added to the local administer account as required when hosting the FSW on a server that is not an Exchange Server. My main question besides confirming that the information I provided above is correct, is what do I do about the CAS array setup, I have gone through all the steps of setting that up and the only thing I have left to do is to create an actual CAS array and then add the 2 Mailboxes to it. From what I have read you only need to setup one CAS Array because you cannot have two CAS Array's in the same Active Directory site, I am also reading that NLB cannot work with a DAG, but NLB was already created on my half way completed setup on my first CAS configuration. If NLB cannot work with a DAG, is there a way I can remove the NLB from my partially configured CAS on my first Server? Should I remove it on just continue and completed the CAS Array Setup? My main concern is to make sure if one Server goes down for either maintenance or another reason I want to have failover for my MB, which the DAG should provide and since all three roles are on both Servers, that should be all I really need for ensuring that I still have Exchange Services available to my customers. This is a small network less than 150 customers and we do not be use OWA, Outlook Web App or anything of that nature.