Decommissioning a Domain Controller

[TNGPicard]

Howdy All,

I inherited this network I manage about 19 months ago and am finally getting to make some very needed changes! Right now ONE of my domain controllers is also an exchange 2003 server (I didn't do this!) and servs up not only all the goodness of exchange but DHCP, DNS, Printers, Files and NTP -- all of this in 1gb of RAM.

So since I need to add more exchange users I'm moving everything but exchange off of the box (finally!). Files and printers are easy enough and I can handle all of the remappings and what not easy enough.

DHCP moving to the new server looks like it has a well defined path and should move easy enough (and if not, I don't have that many reservations and can recreate them if really necessary).

DNS is all ADI zones so I'm not to worried about moving those records.

The server has the following FSMO roles that will need to be moved:
- Schema, PDC Emulator, Infastructure (RID and Domain tree are handeled by my other DC)


Both of my existing domain controllers are global catalogs.


I'm not moving any of this stuff to an existing server, I'm purchasing a new server to move all this stuff on to (actually two, one will handle ONLY file and printers and will not be a DC)

I am only dealing with one domain and thus one forest. The domain Functional Level is Windows Server 2003, the forest functional level is Windows 2000.

So here is my question: What are the gotchas in this process, does anybody have a well defined check list for checking and verifying everything that needs to be moved (generally, everybody's environment is a little different) prior to removing this machine as a domain controller. Exchange always complicates matters so what should I look out for when I go to remove the domain controller role on the exchange side?

Any advice or tips from other people having gone through or in the process of going through and cleaning this process up would be greatly appreciated.

Mark At LMFJ

 

[58sniper]

You can't remove the DC role from an Exchange box. Doing so will permanently break Exchange.

Your options are to build a temp Exchange box, move everything to it, then remove Exchange from the old box, demote it, reinstall Exchange, and move things back.

Pat Richard
Microsoft Exchange MVP

 

[TNGPicard]

Yikes! Glad I posted some back here! all I can say is CRAP!.

Well, I'm still going to move as much as I can off of the exchange box so all it has to do is exchange stuff.

Mark

 

[Atomic]

Regarding 58Sniper reply.

I was not aware that you could not remove a DC role from an Exchange box. However, as I have just done this (last month), can you please let me know what isn't working any more? Or at least why you can't do this..?

Thanks

Martyn

 

[TNGPicard]

I found this article the other day after 58Sniper's post the other day:

http://blogs.brnets.com/michael/archive/2005/01/24/319.aspx

It explained it very well, the site is having some problems right now so I can't pull it back up.

Lots of google searching and reading is telling me that sometimes it works, sometimes it doesn't. I'm not an Exchange guru, I'm planning on buying new hardware and upgrading to exchange 2007 in a few months but that does not solve my immediate problems so I'm going to go ahead and bring in another DC and take every service I can off of my exchange box including DHCP and DNS and move the FSMO roles it contains over to the new DC.

ML

 

[pogi05]

Atomic,

While I too have no specifics as to what is broken when dcpromo'ing an Exchange Server, I worked in a situation very similar to TNGPicard's and my test environment was quirky after uninstalling AD from an Exchange server.

I'm not sure what your setup is, but if possible it may not be bad to look into rebuilding your Exchange installation on that server. Again, it's not necessary but may prevent problems down the road.

Thanks,

Chris

 

[sutors]

just to add: decommissioning DC with exchange on it puts you in an unsupported state if you ever consider calling MS for help with your exchange server.

Lukasz

Lukasz

 

[Atomic]

OK, I'll go with the flow on this and park that one in case I come across it again.

Thanks

Martyn

 

[58sniper]

One of the biggest issues I'm aware of is that if Exchange is on a DC that's a GC, and the DC/GC roles are removed, it won't ever look at another GC. And, since Microsoft won't support it, you're really kinda out of luck.

Pat Richard
Microsoft Exchange MVP