Hi, We have 3 DCs, and one of them is going bad, how do I go about rebuilding that machine, I was going to format it and reinstall everything again. Do I need to first, demote it, then re-prompt it ? Do I need to chang anything on other DCs? Thanks !

You should most definately DCPROMO down this DC. Otherwise, you will leave behind references in AD which will require manually clean-up. Before you DCPROMO the server down, you can do some proactive work such as ensure that one or more of your other DCs are configured as a Global Catalog Server (GC), move the FSMO roles to another DC, and if the DC you are demoting is providing any services such as DNS, WINS, DHCP, move that off before the demotion. Other than that, the process should be very smooth. Visit: anITKB.com, an IT Knowledge Base.

If the server is down, you need to perform a metadata cleanup first. Here are the details: http://technet.microsoft.com/en-us/library/cc736378(WS.10).aspx otherwise perform DCPROMO down to remove this DC from Domain. Then reinstall the OS and join it to the domain and perform DCPROMO. Select “additional DC for the Domain” option: http://msdn.microsoft.com/en-us/library/ee797379(CS.10).aspx Santhosh Sivarajan | MCTS, MCSE (W2K3/W2K/NT4), MCSA (W2K3/W2K/MSG), CCNA, Network+ Houston, TX http://blogs.sivarajan.com/ http://publications.sivarajan.com/ This posting is provided "AS IS" with no warranties, and confers no rights.

Hi, Before you demote a domain controller, verify that this domain controller is not the only global catalog, DNS server and that it does not hold an operations master role. Please refer to the Caution and Notes on this article: Demote a domain controller http://technet.microsoft.com/en-us/library/cc740017(WS.10).aspx After removing the problem DC, please make sure to perform metadata cleanup: Active Directory Metadata Cleanup http://msmvps.com/blogs/mweber/archive/2010/05/16/active-directory-metadata-cleanup.aspx Regards, Bruce

thanks for all the answer guys ! most appreciated!

No problem and thanks for the update. Santhosh Sivarajan | MCTS, MCSE (W2K3/W2K/NT4), MCSA (W2K3/W2K/MSG), CCNA, Network+ Houston, TX http://blogs.sivarajan.com/ http://publications.sivarajan.com/ This posting is provided "AS IS" with no warranties, and confers no rights.

Hi, Glad to hear the information I provided was useful. If you have more questions in the future, you’re welcomed to this forum. Regards, Bruce