Why can I not have a purely virtualized SAN in vSphere 5? I cannot enable the iSCSI port binding option (it is greyed out and unchecked) or add the VMkernel to the iSCSI software host bus adapter unless there is a physical NIC associated with the vSwitch.
You can have a purely virtualized SAN in vSphere/ESXi. I do it with NFS often. Did you create a new vSwitch for your storage network?