Found the answer. See CSV Ownership. During migration, copy cluster can be use to migrate cluster roles. But the disk cannot be online on both cluster as one cluster hold the ownership. So the steps is, you must run the copy cluster first, then turn off your VM's on old cluster, and make the CSV offline. Then make the CSV online on other node, fire up your VM's on your new node with new cluster. This resolved my question. 
Dell administrator and specialist out there.. , I need help!  I have a VRTX and running 2 nodes Windows Server 2012 Hyper-V Cluster. I want to migrate to Windows Server 2012 R2 Hyper-V cluster (using another 2 blades) but will use existing storage. Seems that I cant use existing storage even I have assigned the virtual disk from the CMC. From the Failover Cluster Manager>Disk, I got error "The requested resource is in use". In cluster event log, I got: 1069 -  Cluster resource 'Cluster Disk 1' of type 'Physical Disk' in clustered role '9c5e9411-cddd-4496-8c57-9be758e788a1' failed. 1038 - Ownership of cluster disk 'Cluster Disk 1' has been unexpectedly lost by this node  I am currently stucked here. Cant make the 2012 R2 to have access to existing cluster disk. Can someone point me what is my mistake and if there is any steps to be made on CMC or Windows? Thanks in advance for your help.. 
DELL VRTX Shared Storage for cluster