DFS redesign ideas?

Question

Hi,
Basically I am looking for a few ideas on how to redesign our file servers.
We have multiple physical file servers and a few virtual servers and what is replicated and what is not is quite confusing. Total storage size is around 6TB made up of home directories, and shared resources - no particularly special file types etc. Using
DFS with home directories however does mean that I need to essentially have only a single point of reference to be supported by Microsoft as per:
http://blogs.technet.com/b/askds/archive/2010/09/01/microsoft-s-support-statement-around-replicated-user-profile-data.aspx
What I am thinking about doing is consolidating everything onto 4 servers.
We have a large single site with a few remote sites. The remote sites have had their links upgraded to 1Gb and we have been removing our server infrastructure from these areas due to not having environmental/physical space/security in place.
On our main site we have two separate buildings which each contain a SAN (Not linked to each other).
Microsoft's guides show concepts of using a DFS Failover Cluster in a main site with replication to a single server at a remote site.
I could do this model but just in one site, but due to the fact I have two equally sized SAN's on the main site, the issue with this is that I would like to spread the load to both SAN's. Therefore if I have anything running on the single server as primary I
am creating an SPOF.
What I am thinking of doing is create 2 x 2 node DFS Failover Clusters (One in each building connected to that building's SAN).
This means:
I can load balance the primary DFS shares at the cluster level (SAN's)
Rapid failover can occur if needed between individual nodes within a cluster
The single point of failure (Storage) in just using a single DFS cluster is eliminated
However I am not sure if this is supported or recommended?

Answer 1

Not sure if i'm misunderstanding things here, but the way I see it you have three levels at which you need to provide redundancy
DFS Namespace servers - I would suggest you host these on your domain controllers that you already have, actual file load will be minimal and they will provide adequate failover.  It also has the benifit of keeping your namespaces all under the same
parent domain.  \\domainname\share\foldertarget
DFS Folder Targets - These point to shares on your actual file servers that do the heavy lifting, one copy of each share per SAN with DFS replication to keep them in sync.
The actual file servers - A standard cluster running a clustered file service role.
This way you have each san servering files via a 2 node file cluster.  (active/passive)
Each file cluster is replicating accross to the other via DFS replication. (active/active)
Let your domain controllers handle the actuall exposing of DFS shares. (active/active)
The only issue will be keeping on top of DFS replication between your two file server clusters to make sure users in the same building do not see differnet files depending on which file server cluster they are currently using.
Hope this helps.