with vSphere 5 the vmfs volume size is still limited to the 2TB-512 for each individual VMFS volume, but you can use extents on them to grow much larger.
- There is now support for passthru RDMs to be ~ 60TB in size.- thats not what you are trying to accomplish so thats not going to work
- Non-passthru RDMs are still limited to 2TB - 512 bytes.
- Both upgraded VMFS-5 & newly created VMFS-5 support the larger passthru RDM.