This is a question that no one in Microsoft, nor the techs here can answer. We are moving ahead with planning for Exchange 2007 but we want to use CCR as it claims it can recover from a Datacenter Failure. How is it done? I'll go intomore details: Site A is 10.20.0.0/16 Site B is 10.21.0.0/16 How are we going to setup the cluster service? Don't the nodes have to see each other and be on the same network? Thanks guys, HT