I've had to create a microsoft cluster on a Dell Vertex (or VRTX), I do not know if you know exactly what it is, is a low-cost blade integrated infrastructure with the server part, networking and storage.
The peculiar thing of the storage part is that it is run by a raid controller 8 perc that normally is a single server controller, but in this case it has been modified to allow shared access to the luns created on VRTX. This peculiarity generates some problems when we have to create a microsoft cluster as during the validation windows controls the type of disk/volume to see if it is a shared disk, but, being run by a perc, it sees them as local disks and then validation fails.
To overcome this problem we must make a registry change on all nodes that are part of the cluster, in particular you need to add a DWORD in this path:
Re-execute the validation check and you will see that, this time, it will work!