We have 2 domain controllers that we're replacing. I believe i have all the MS articles for that, but I'm wondering if there is anything i will need to change in Exchange/AD/DNS when the new domain controllers are up and running. I don't want to"break" Exchange. Thanks

Steve, It seems like you're adding additional Domain Controllers to your existing Active Directory environment to eventually be able to demote and switch off your existing Domain Controllers. Replacing Domain Controllers in this fashion is mostly about checking proper replication, recreating Global Catalog (GC) servers, and transferring FSMO roles. One of the important things to remember in Exchange environments is to reboot the Active Directory Domain Controller after making it a Global Catalog (GC) server. The Graphical User Interface (GUI) will not prompt you to do so, but your Domain Controller will only start talking MAPI after doing so.