Shared VMFS Volume Requirements
A DRS cluster has certain shared VMFS volume requirements.
Configure all managed hosts to use shared VMFS volumes.
■ Place the disks of all virtual machines on VMFS volumes that are accessible by source and destination hosts.
■ Ensure the VMFS volume is sufficiently large to store all virtual disks for your virtual machines.
■ Ensure all VMFS volumes on source and destination hosts use volume names, and all virtual machines use those volume names for specifying the virtual disks.