All, Looking at a new exchange design where my customer has a LAN extension to another site (10Mb connection) and what I thought about doing rather than implementing a DAC setup was build the server in my 2nd site with the CAS, HT & MB roles add it to my DAG and possibly add it to my CAS array. I think this might go against MS best practices so am looking for some technical do's and dont's. My exchange design plan is to have in the production site 2 x CAS+HT and 2 x MB - have a CAS array setup using WNLB and a DAG setup with 2 live databases on 1 MB server and another 2 live databases on the other MB server with replica's of these DB's to the other MB server. My plan for the "DR" site was not to implement a DAC but rather use the LAN extension and add this "DR" server to the DAG and CAS array therefore if I have outage/DR and can easily get my users to connect to this exchange box (I do have a DC in my DR site). I am not sure on the CAS array side of things as I don't want users connecting via this server for live/production work so I guess the question is if I omit this box from my CAS array how can I get the users to connect to this device in the event of a DR senario would I just need to amend the mapi profile? Thanks