2012R2 cluster csv - no access to storage and in redirected mode

Hi,

I have a two node 2012R2 cluster backed by a shared SAS JBOD. The cluster passes all validation tests - most specifically it passes the storage checks with flying colours.

It's using shared storage spaces which was configured and working perfectly with a quorum vdisk. The quorum can be moved between nodes without issue when moving the Storage Pool owner.

When adding a new vdisk to clustered shared volumes, immediately one of the nodes goes into redirected mode reporting that all storage paths are inaccessible. Snippet of the event; 

Cluster Shared Volume 'Volume1' ('Cluster Virtual Disk (Test)') is no longer directly accessible from this cluster node

If I change the CSV owner, the bad node stops redirecting and the other starts redirecting.

To visualise the physical config - it looks like this;

My MPIO paths are configured, and the devices show up correctly with all paths available (on both nodes)

Extraction from the Get-ClusterLog - I think I've found the part that shows exactly what's happening - but I don't know what it means...

00000a98.00000b10::2013/09/10-19:55:30.842 INFO  [RES] Physical Disk <Cluster Virtual Disk (VirtualisationStorage)>: HardDiskpQueryDiskFromStm: ClusterStmFindDisk returned error=2147943568
00000a98.00000b10::2013/09/10-19:55:30.842 ERR   [RES] Physical Disk <Cluster Virtual Disk (VirtualisationStorage)>: Failed to locate disk, status -2147023728
00000a98.00000b10::2013/09/10-19:55:30.842 ERR   [RES] Physical Disk <Cluster Virtual Disk (VirtualisationStorage)>: FindTheDiskNumber: Unable to find disk. Error: '2147943568'.
000005ec.00000908::2013/09/10-19:55:30.842 INFO  [RCM] Group da40e60c-7971-4323-bd45-3a19f36599db: done going through resources, returning true
000005ec.00000908::2013/09/10-19:55:30.842 INFO  [RCM] da40e60c-7971-4323-bd45-3a19f36599db should not fail back from 2 due to possible owners
000005ec.00000908::2013/09/10-19:55:30.842 INFO  [RCM] da40e60c-7971-4323-bd45-3a19f36599db should not fail back from 2 due to paused nodes
00000a98.00000b10::2013/09/10-19:55:30.842 ERR   [RHS] Error 2147943568 from ResourceControl for resource Cluster Virtual Disk (VirtualisationStorage).
000005ec.000005b4::2013/09/10-19:55:30.842 ERR   [DCM] failed to get diskNumber, status 1

Thanks and regards,

Matt.