I have 3 Server 2003 DCs with Exchange 2010 on my system. We have purchased 3 new server 2012 R2 systems. I am looking for the best way to upgrade the 2003 to 2012 without hurting the exchange 2010.
My plan of attack is to add each server to the domain already done. Then Promote each to a DC one at a time. When all are added move roles and update the levels.
It is my understanding that this path will cause no interruption with the domain and exchange. Am I correct with this or is there some hidden stuff I don't know.