With the release of vSphere 7, one of the core storage features is Shared VMDKs on VMFS. (See vSphere 7 Cores Storage details here.)
Many clustered applications require SCSI-3 persistent reservation (SCSI3-PR) to be able to share disks between nodes in the cluster application. Microsoft’s Windows Server Failover Cluster (WSFC) is the most common example. This requirement is one of the primary reasons customers are still using RDMs. In vSphere 6.7, we announced SCSI3-PR support for vVols, and now with the release of vSphere 7, we’ve added SCSI3-PR support in VMFS on FC. For more detail, head over to core.vmware.com.
The next question then arises, how do you migrate from a pRDM to a Shared VMDK? You’re in luck; I’ve created an article and video detailing the process. The process outlined is vendor agnostic so that it will work with any array compatible with the new vSphere 7 feature. In some cases, your array vendor may have another process for migrating, so make sure to check with your storage vendor first.
The article and video are available on core.vmware.com.