In order to add an additional domain controller to an existing domain, DCPromo must be used to complete the task. The process will install the AD DS on the Windows Server, join the machine to the domain and replicate all partitions from the existing domain controller. The steps for running DCPromo to promote a server to DC have been well documented. They can be done either through the Windows Interface for user attended installation, or via an answer file for unattended installation. This blog will focus on what really happens after the user input is taken and the real installation starts. Hopefully this can help readers have a better understanding of domain controller installation process, so that they can have effective debugging if any problem arises.
