Add a DFS Namespace server

DFS namespace and DFS Replication are completely separate services that have nothing to do with each other. The DFS namespace share root should be a new share of an empty directory. In some versions of Windows, the default location for namespace shares is c:\dfsroots.  I don't remember if 2003 does that, it may have started in 2008/R2. As long as your DFS namespace share is an empty directory outside of any DFS Replication hierarchy you should be fine. Don't forget that you need to make sure that the share and NTFS permissions are correct. My permissions are usually everyone full for the share, and only system has full for NTFS, and everyone else, including administrators, only has read, and that there are no special permissions. The defaults allow create access inside the DFS namespace share, so you get files appearing higher up in the namespace than the actual shares where you want them to be and they only appear when attached to a specific namespace server because anything under the physical namespace share that isn't a DFS link isn't replicated.

Adding existing Replica server as name space server in existing DFS will not delete data.
It will create brand new directory structure as C:\DFSRoot\DFsNameSpace on replica server which is not already there.
This is standard behaviour since 2003 R2 OS
Just change default perms to administrators have full control access and everyone has read access on namespace root directory which you can set from edit settings tab.

Also you need to take below actions as well to share folders on replica server
To enable file sharing on a replicated folder and optionally add the folder to a DFS namespace, use the following procedures:

To share a replicated folder

1. Click Start , point to Administrative Tools , and then click DFS Management .

2. In the console tree, under the Replication node, click the replication group that contains the replicated folder you want to share.

3. In the details pane, on the Replicated Folders tab, right-click the replicated folder that you want to share, and then click Share and Publish in Namespace .

4. On the Publishing Method page, choose Share the replicated folder or Share and Publish in Namespace , and then follow the steps in the wizard.

http://technet.microsoft.com/en-us/library/cc772379.aspx

Mahesh

I guess the thing that is confusing me is the DFS namespace root share.  If the namespace already exists why does it create a new share?  So for instance, on this server, D:\data\ already contains the directories that are shared out through DFS.  These directories are replicated to other servers and DFS directs users to the appropriate server depending on which site they are at.  Or...what if I wanted a server that just responded to namespace queries and did not contain any of the data?
The directory it wants to create is c:\dfsroots as you suspected.  I do not see this directory on either of the other servers, but this all pre-dates my involvement with this environment.
Again, my major concern is affecting the existing data.  Also a little more background...at one point the server that contains data but is not a namespace server was a namespace server, but was rebuilt after a crash with a new name and the data copied back and replication repaired, but the lack of a namespace server at that site was never addressed.

To clarify, there are already folders on this server that are shared out through DFS and they are also replicated.  What goes in the c:\dfsroots\ directory?  It seems I would not need it.