DFS-R vs DFS role

Since 2008 when there was no 2003 AD before hand, the replication of sysvol is done using DFS-r (replication)

DFS is part of file services role and does not exist as a role onto itself.

I am not quite sure I understand your question.

under file services, you have DFS management under which you have namespace and replication?
The two components are you would use DFS-R to make sure the data in the share is replicated between/among the namespace target servers.

i.e. you have serverA\share1 serverb\share1 and serverc\share1
within the replication group named share1 naming convention is up to you for this example I'll name the replication group using the share involved.
The location of share1 on each server can be the same or can be different, during the configuration of the replication group, you have to make sure to properly select the location.
i.e. servera will have the data in e:\share1 name of the folder is up to you
serverb will have the data in f:\share1
serverc will have the data on d:\share1
If you starting from scratch, the reference server when configuring the replication group is not important, but if you already have a server i.e. server1\share1 that was previously used as a server based share versus a domain based share and you are transitioning to a domain based share, you have to use server1 as the reference serve. this way the data on server1 will be treated as authoritative/valid and all its data will be replicated to the other members of the replication group.

The topology of the replication group hub and spoke, mesh will deal with the data flow/synchronization ..........

I think I went way over what your question was. but hopefully the info answers and clarifies what dfs/DFS-R are and do.

There is no DFS role. There are two different services that share the moniker DFS: DFS Replication, and DFS Namespace. DFS Replication replicates files. You may not see it "installed" if it is only replicating SYSVOL for AD. You can go ahead and add it to any servers that you want to participate in DFS-R for user files. Adding the DFS Replication won't affect your existing replication of SYSVOL.

The only thing that sounds not quite right with your environment is that you have only 1 server serving your DFS namespace. You should have at least two servers hosting your DFS namespace(s). I like to have one domain controller in each site host the DFS namespace.

I think I understand.  What was and IS throwing me off is that the Role of DFS is not installed.  The NameSpace is not installed.  When I look under roles, neither of the two is installed.

Yet, I see both services up and running and we have DFS shares in play.

What's the difference between this stuff running with and without the role actually installed on the roles screen?

The sysvol is a domain based share with every dc target server.

Do you have the fileserver services installed?

Yes, file services is installed, but both DFS options are NOT checked.