DNS Primary Servers

There is no one answer here.  If you have a single domain and running active directory integrated zones then generally every DC will also be a DNS server hosing the zone.  DNS information will replicate to ever DC (you can set the replication scope also)

Thanks

Mike

You can only have a single PDC (Primary Domain Controller) in an AD domain as it is a special role. But there are no real limitation on the number of DNS servers or zones you can have. (There are but you are unlikely to hit it with an SME setup http://technet.microsoft.com/en-us/library/active-directory-maximum-limits-scalability%28v=ws.10%29.aspx)

Depending on the number of users and branch connectivity at the remote sites, you can have a local DC or do away with it altogether and configure the clients to connect to the primary site.

I have local DC's that are Global Catalog servers in each site.  In DNS should the foward lookup zone be a Primary Zone and not a Secondary Zone even though it is the same domain?

It can be primary but do you know why it is set as primary and not active directory integrated?  

Thanks

Mike

They are AD Integrated ...  I was referring to when I created the Zone on each site's DC I selected "Primary Zone" and not "Secondary" or "Stub" ...

-marc