Windows Server 2003 DC

It would be far easier to add the 2012 server to the domain and promote it using the Roles and Features wizard.  There is the potential for a few gotchas so I would do the following before adding your 2012 server.  

1.  I would perform a DCDIAG to determine the current health of the domain.
2.  You could potentially have a corrupted FRS Database on the 2003 Server.  This is quite a common occurance.  Luckily though, you can determine the FRS health by using FRSDiag (or browsing through your Event Logs).

I would recommend reading this blog concerning FRSDiag.

Specifically the event you are looking to find is Event ID 13568:If you do find that your FRS Database is in a JRNL_WRAP state, you can easily repair this by reinitializing the FRS replica sets.  Microsoft has a TID that discusses the process:  http://support.microsoft.com/kb/290762

In a nutshell, the process involves stopping the FRS service, editing the HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\NtFrs\Parameters\Backup/Restore\Process at Startup\BurFlags setting in the registry and restarting the FRS service.

You first want to ensure that you have stopped the FRS service on all DC's.  Then on the 2003 server that holds the PDCe FSMO role, perform the following steps.
1. Modify the registry setting for the BurFlags key using a value of D4.
2. Restart the FRS service.
On your remaining DC's:
1. Modify the registry setting for the BurFlags key using a value of D2.
2. Restart the FRS service.
Look for event 13516 to indicate that the FRS is no longer preventing the 2012 server from becomming a domain controller.

3.  You may need to modify the component services on your 2003 DC before ADPREP will successfully run:

https:/Q_28584877.html#a40514872

4.  Kerberos Authentication can fail intermittently (Microsoft has a hotfix for this issue) - http://blogs.technet.com/b/askds/archive/2014/07/23/it-turns-out-that-weird-things-can-happen-when-you-mix-windows-server-2003-and-windows-server-2012-r2-domain-controllers.aspx

After doing the above, I would then use the Active Directory Domain Service wizard to add the 2012 server to the domain: https://blogs.technet.microsoft.com/canitpro/2013/05/05/step-by-step-adding-a-windows-server-2012-domain-controller-to-an-existing-windows-server-2003-network/

I would also add that since DFRS is now the preferred method for storing AD related replica files (SYSVOL, Policies, etc.), that you migrate FRS over to DFRS as a part of the steps you have outlined above.

https://blogs.technet.microsoft.com/filecab/2014/06/25/streamlined-migration-of-frs-to-dfsr-sysvol/

Then you would transfer the roles to the new server using the method described in the link in the previous post - https://social.technet.microsoft.com/wiki/contents/articles/832.transferring-fsmo-roles-in-windows-server-2008.aspx

After that you can demote your 2003 server and raise your Forest Functional Level/Domain Functional Level to Windows Server 2008 (if your 2008 server is R2, then you can raise them to Windows Server 2008 R2)

https://technet.microsoft.com/en-us/library/understanding-active-directory-functional-levels(v=ws.10).aspx

-saige-

No comment has been added to this question in more than 21 days, so it is now classified as abandoned.

I have recommended this question be closed as follows:

Accept: Sajid Shaik M (https:#a42177740)

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