The Dell MD SRA uses either a Synchronous Replication premium feature or an Asynchronous Replication premium feature, or both, along with the Snapshot premium feature to facilitate failover and test Failover. Also, based on your environment, enable the storage partitioning, sufficient for the number of hosts connected to the storage array. VMware vCenter SRM and the Dell MD SRA do not operate without these features enabled on the MD storage array.