I'm Oscar Mas and when we implemented a system based on XenDesktop, working with DFS Namespace is a must (DFS-N). What this Microsoft Role allows us, is to be able to manage different Storages, creating a single point of access through our DFS-N in a transparent manner, without having to know exactly where the data is located.

Behind a DFS-N we can find different Storages, as they could be: QNAP, Linux with Samba, Synology, FreeNAS, etc... if we simply have a DFS-N system implemented in our infrastructure (dc.ilba.cat), in the face of a fall in the DFS Role, We will be plunged into a problem, since our XenDesktop platform will not be able to access any type of resources. What I'm going to show you is how to implement a second DFS-N server, so that in the event of a crash of our primary DFS-N server (dc.ilba.cat), take over from our second DFS-N server (srvdc1.ilba.cat)

The first step we have to take, is to install the DFS-N Role on our secondary server: srvdc1.ilba.cat. In my case, I have installed the DFS-R Role in case in the future we would like to use the replication technology provided by Microsoft.

Once the DFS-N role is installed on our second server, we'll go to our DFS-N system (dc.ilba.cat) and in the root we will tell you that we want to add a new namespace server (DFS-N)

We will tell you the name of the server that will do the secondary DFS-N functionalities, which in my case is srvdc1.ilba.cat.

And we will already have added our second DFS-N server. To be able to verify which of the two is the asset, we will be able to observe it from the PowerShell console:

Get-DfsnServerConfiguration -ComputerName "SRVDC1"
Get-DfsnServerConfiguration -ComputerName "DC"

To verify proper operation, We can for the DFS role of the primary server (dc.ilba.cat) and via PowerShell, see that it has actually switched and now our secondary server will become primary.

When the DFS-N service is stopped from the server dc.ilba.cat, we will be able to observe how our second DFS-N server is launched (srvdc1.ilba.cat). Run:

dfsutil /pktinfo

Remember that clients keep a default cache of access to DFS-N resources. That means that if we stopped the two DFS-N systems, During a predetermined time we could access the resources, but after that time the accesses to our DFS-N system would stop working.

I hope I have a server of help for you!