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Replace primary domain controller

I have 2 servers running Windows Server 2003. 1 server is the primary domain controller with AD, DNS and DHCP. The other server is my email server with active directory.

I need to demote my primary domain controller to a file server and install a new server I just purchased as my primary domain controller running Server 2008 with DNS and DHCP. The email server should remain as is with no changes.

What detailed steps do I need to follow to make this transition smooth. Please provide details as I have never replaced domain controllers before. Thanks.
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Top Expert 2012
Commented:
Here is a step by step guide on the process.

http://www.experts-exchange.com/OS/Microsoft_Operating_Systems/Server/Windows_Server_2008/Q_23665224.html

If your new OS is Windows 2008 R2 then you need to run adprep32 on the a 32-bit DC instead of adprep which is only for a 64-bit DC when it comes to Windows 2008 server R2
Paul MacDonaldDirector, Information Systems
Commented:
  1. Add the 2008 server to the network.
  2. Make the 2008 server a domain controller
  3. Transfer the PDC emulator role to the 2008 server (http://www.petri.co.il/transferring_fsmo_roles.htm)
  4. Demote the original PDC emulator (http://technet.microsoft.com/en-us/library/cc740017(WS.10).aspx)
Top Expert 2013
Commented:
Take a look at this question I helped with over at the TechNet forums

http://social.technet.microsoft.com/Forums/en-US/winserverDS/thread/181468e7-d1f8-470a-8ffa-718ada794dbf

The good news here is that you will at some point be running three DCs and only when you can make sure things are ok before demoting the 2003 box.  Lot's of great info and links on that thread.

one thing all DCs are equal but I'm guessing when you say primary domain controller that one holds the FSMO roles.

Thanks

Mike
Lee W, MVPTechnology and Business Process Advisor
Most Valuable Expert 2013
Commented:
You don't have a primary domain controller.  In active directory, everything is a DC.  Period.  There are FSMO roles that perform critical functions, but they COULD be divided up between 2-5 servers.  A PDC is also the only writable domain controller in a domain - BDCs are read only copies... In active Directory, EVERYTHING is writable.  

As for the process, there are already too many cooks giving instruction, so I'll just say what I usually say since I don't think any link here talks about it.

1.  Perform system state backups of EVERYTHING first.
2.  Run DCDIAG and NETDIAG on both DCs to start - correct any issues found.
3.  continue with some variation of everyone else's instructions.

Author

Commented:
1 follow-up question...

My current servers are 32bit, but my new PDC will be 64bit. Does that make a difference in your posted in instructions? dariusg already pointed out that I should run adprep instead of adprep32.
Lee W, MVPTechnology and Business Process Advisor
Most Valuable Expert 2013
Commented:
Other than which version of the ADPREP utility you run, there should be no difference between a 64 bit and a 32 bit DC.
Top Expert 2013
Commented:
One quick thing if your new DC will be 64 bit you may want to think about going straight to 2008 R2 at this point.

Thanks

Mike
Commented:
First thing to do before migrating roles (unless you've done it already) is doing a domain & forest prep (ADprep as stated above) on the domain before putting the 2008 R2 online.

It would probably be best to get the new DC online & migrate the DNS roles, Server 2008 R2 has some apps that aid with migrating services. Remember that if you migrate the DNS & DHCP services you have to point the clients to the new DNS server (if static addesses).

Author

Commented:
So to confirm, here are the steps I should follow in order:

1. Install Server 2008 R2 on new server.
2. Join new server to domain as a member server.
3. Run adprep (forrest prep, domain prep) on new server.
4. Promote new server to domain controller by running DCPROMO.
5. Make the new server a Global Catalog Server.
6. Transfer FSMO roles from old DC to new server.
7. Install DNS and DHCP on new server.
8. Demote old DC to file server by removing AD, DNS and DHCP.

Did I miss anything?
Paul MacDonaldDirector, Information Systems
Commented:
I would move step (7) up to just after step (1), but your process seems okay to me.
Lee W, MVPTechnology and Business Process Advisor
Most Valuable Expert 2013
Commented:
2.3. BACKUP all existing DCs
2.6. Run DCDIAG and NETDIAG and correct issues found.
Top Expert 2012
Commented:
I would before moving any roles and adding this DC as a GC run dcdiag on the new server. If you don't have any errors you are safe to proceed.

Also, before moving roles I would let the system fully replicate and settle before moving any roles as well.

Don't rush.

Author

Commented:
Everyone here has been a great help so I've split points among everyone. I will make this server switch in the comings weeks. Hope all goes well according to these posts. Thanks again for all the help.