Merging two Domains in one AD RRS feed

  • General discussion

  • Hello,

    I consider that our case is particular and this is the reason why I am opening a new discussion. Please consider that I need precise answers on this specific situation so please help me.

    The scenario is one where 2 companies merge. The companies has several offices in separate geographical locations connected through VPN tunnels.

    There are two separate Domains „domain-A” and „Domain-B” each one with a single Active Directory Structure. Each domain is controlled by Domain Controllers in two of the main offices. Domain A has around 100 registered users and Domain B has 600. There are two Exchange servers, one for each domain. The picture is as follows:


    Domain A – 600 users – location A                    |   Domain B – 100 – users – location B


    DC1- Windows 2003                                                |   (v)DC1 - Windows 2008

    DC2 - Windows 2003                                               |   (v)DC2 - Windows 2008

    (v)DC3 – Windows 2003                                         |  

    (v)EXCH – Windows 2008 – Exchange 2007    |   (v)EXCCH – Windows 2008 – Exchange 2007


    (v)= virtualised

    The objective is to upgrade and restructure the domains / merge theese domains into a new domain „Domain-C” without interrupting the activity in any way (we cannot take any risks).

    Domanin C – would have 700 users and would be installed on Windows 2012 platform. The structure image should be:


    Domain C – 700 users – location A                     |   Domain C –  location B


    DC1- Windows 2012                                                |   (v)Read only DC - Windows 2012 –for fast authentication

    DC2 - Windows 2012                                               |  

    (v)DC3 – Windows 2012                                         |  

    (v)EXCH – Windows 2012 – Exchange 2010    |   (v)EXCH – Windows 2008 – Exchange 2010 – 100 mailboxes


    (v)= virtualised

    So I am looking for any suggestions on the best way to handle this.

    • Edited by Nilatack Saturday, September 21, 2013 8:14 PM wrong title
    Saturday, September 21, 2013 8:11 PM

All replies

  • Use either native migration tools or third party ones. Search ADMT, adprep, migration keywords by Google.

    For Exchange migration refer to Exchange forum.

    Detailed description of migration procedure is beyound the scope of current forum.



    Sunday, September 22, 2013 9:24 AM
  • Hello,

    as the new domain should start with Windows server 2012 DCs be aware that ADMT will NOT be supported on it and is blocked during installation on a Windows server 2012 http://support.microsoft.com/kb/2753560/en-us.

    So you have to use Windows server 2008 R2 DCs to use ADMT for the migration and then upgrade to a full Windows server 2012 domain.

    For the Exchange versions assure with http://technet.microsoft.com/en-us/library/ff728623(v=exchg.150).aspx that all requirements are fulfilled.

    Best regards

    Meinolf Weber
    Microsoft MVP - Directory Services
    My Blog: http://msmvps.com/blogs/mweber/

    Disclaimer: This posting is provided AS IS with no warranties or guarantees and confers no rights.

    Sunday, October 20, 2013 5:54 PM