One of the cool new features of Windows 2008 R2 is the possibility to add a windows failover cluster as a member of a DFS-r replication group. This possibility creates a highly available replication service.
A useful scenario for a failover clustered DFS-r service is the clustering of a central DFSR-Node in a multi-site replication group. The data of the branch offices is replicated to the central site, where it is safely stored, archived and backupped.
As you can see above, in the central site we have created a two-node failover cluster. Both nodes are connected to a shared storage medium. This can be a shared SCSI or SAS solution but also a FC or iSCSI SAN solution. In event of a failure of the priamary node, the windows failover clustering service will delegate the DFS-R related roles to the secondary node without having to reconfigure the DFS-R service.
But how do we create a DFSR replication group that is using a cluster instead of a fileserver. With the Windows 2008R2 management tools this is really not that hard to do.
- Built your central File-server failover cluster using the built in wizard. Building a cluster has become really easy nowadays.
- Add a file server application/service to your cluster. Again using the builtin wizard. During this process a Client Access Point is created.
- Now we can create a replication group. Remember that the cluster should be running 2008R2. The branch office servers (non clustered) can be running Windows 2003R2 of Windows 2008.
- When we need to add the cluster to the replication group we are using the previously created Client Access Point as the replication member.
That's it for building a highly available DFS-r replication solution.
A more complete guide can be found at the blog of the Windows Storage Team: http://blogs.technet.com/filecab/archive/2009/06/29/deploying-dfs-replication-on-a-windows-failover-cluster-part-i.aspx