Windows Server 2003 Question:

When DC promotion occurs with an existing forest, the Active Directory Installation Wizard contacts an existing DC to update the directory and replicate from the DC the required portions of the directory. If the wizard fails to locate a DC, it performs debugging and reports what caused the failure and how to fix the problem. In order to be located on a network, every DC must register in DNS DC locator DNS records. The Active Directory Installation Wizard verifies a proper configuration of the DNS infrastructure. All DNS configuration debugging and reporting activity is done with the Active Directory Installation Wizard.