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        Which DC Is Selected When Promoting A Member Server To DC?

Section(s): Active Directory , Administrator, Active Directory , Admin , Active Directory, Admin
Published on Nov 11, 2008.
Last Modified on Aug 25, 2008.
Last Modified by Nirmal Sharma.
Rated 1 out of 5 based on 1 votes.

This article discusses the a mechanism used by the DCPromo.exe to select a DC when promoting a member server to Domain Controller.

When you promote a member server to Domain Controller using Dcpromo.exe, the Dcpromo.exe contacts a domain controller available in the domain to replicate the AD Database. If there is only one DC then it always contacts that DC for AD database but what if there are more than one DC?

The Dcpromo process always contacts the DC available in its own site first. If there is no DC in its own site then a DC from the nearest site is contacted. You can check the Dcpromo process and see which DC it contacted during the promotion by opening the DCPROMO.LOG file found at %SystemRoot%\Debug folder. The log file will contain the following lines for the source DC:

07/30 11:58:24 [INFO] Located domain controller DCNAME.domain_name.com for domain domain_name.com

07/30 11:58:24 [INFO] Using site Default-First-Site-Name for server \\DCNAME.domain_name.com

About Nirmal Sharma

Nirmal is a Microsoft MVP in Directory Services and working as a Technical Architect/Consultant. He has been involved in Microsoft Technologies since 1994 and followed the progression of Microsoft Operating Systems and software. He is specialized in Directory Services, Microsoft Clustering, SQL, MOM, Exchange and Citrix. In his spare time, he likes to help others and write "internal" technical articles, white papers and tips on various Microsoft technologies. You can contact him at nirmal_sharma@mvps.org.