Domain Controller/Global Catalog Role

**Mr.Macroney** · 10-04-2008

I am using a new single site domain with more than 3000 users and 4 DCs an Exchange 2007 SCC cluster. DCo1 holds all the rolers and is GC. There was an sms consultant in todays troubleshooting distributiong point performance for package delivery. He information that I should remove the Global Catalog role from DC01, whilst enabling GC status on the DC which is right now not a GC. I think that single site domains should have all DCs as Global Catalog. The removal of the GC role from the current holder of all roles would have what likely impact, whether positive or negative. Any ideas for this thing? Thanks

**Jerry** · 10-04-2008

I guess that with a single domain forest you may as well make them all GCs. Because in a single domain every DC hold virtually everything on a GC anyway. Also, nothin is depending on your network and number of Exchange users but there is no downside to making them all GCs. Are you having any performance issue or are you on verge if such?

Herb Martin · 15-04-2008

Can you tell us whats the rold of the GC? To me, it will not make any sense to have a GC at all in a single site domain, every DC has a copy of the same data. Except that some facilites need the GC to function properly. The logons also require a GC in Native + mode. The universal groups are only on the GCs and the Exchange uses the GC as a Global Address List.

**Hockson** · 16-05-2008

Follow the below article that describes the placement of Active Directory Flexible Single-Master (FSMO) roles in the domain and forest for operations that are best performed on a single domain controller.

http://support.microsoft.com/kb/223346