This is a very simple/stupid question. I think I know the answer but would like to veirfy before I move forward. We have two forests within our company. One is an old one that we have migrated all of our users/applications from. It is running the same domain name as our external website and thus currently hosting the DNS information for that name space. We have a new forest that contains all of our users and their mailboxes. Our Exchange 2010 is on our new forest. It is using a name space that is for internal use only. We plan to demote the last DC of the old forest and thus get rid of its name space internally. We would create a new DNS zone on our new forest to host all of the name resolution that was done with former forest. I believe this is called a Split DNS setup. This should address any DNS/Security Certificate issues with Exchange correct? Is there anything else that we should consider for our Exchange server before we remove the old forest? Thanks, Joe

Will you have internal machines in the public namespace after the old forest are removed? What's the reason that making you move to split DNS? If it's merely because of Exchange cert, you definitely don't need it.

Li - Thanks for the reply. It is because we will have internal machines that user the public namespace for URLs.

We plan to demote the last DC of the old forest and thus get rid of its name space internally. We would create a new DNS zone on our new forest to host all of the name resolution that was done with former forest. I believe this is called a Split DNS setup. This should address any DNS/Security Certificate issues with Exchange correct? Is there anything else that we should consider for our Exchange server before we remove the old forest? Thanks, Joe Hi Joe, It seems to me that you already is running a Split-DNS. Names like www.domain.com and mail.domain.com etc is already resolves to internal IP Addresses right? It really doesn't matter which DNS Server that holds the DNS-Zone so moving it to your DNS Servers in your new forest will be an easy task for you. From an Exchange perspective it will not change anything. Martina Miskovic

Martina - Perfect. I thought that was right just wanted to bounce it off someone else first. Thank you.

Your Welcome Joe! ..and if you have any DNS/Security Certificate issues as you mentioned, post them and we will try and help you with those. Martina Miskovic