Procedure for Storage vMotion of Virtual Machines with Shared RDMs (WSFC) and VMDKs

Products

• VMware vCenter Server

Issue/Introduction

Symptoms:

• RDMs are configures as physical compatibility mode 
• Requirement to move VMDKs to a new datastore while maintaining RDM connectivity.
• Need to ensure RDM pointer files are correctly relocated or recreated on the destination storage.

Environment

VMware vSphere ESXi 7.x
VMware vSphere ESXi 8.x
VMware vSphere ESXi 9.x

Resolution

Pre-Checks:

• Take a backup of all involved VMs.
• Note down the current SCSI controller settings, SCSI number and SCSI ID to which every Disk is connected, as the disks will need to be attached to the same SCSI ID when they are attached back once the migration is complete
• Record the datastore paths of disks

Procedure to follow:

• Shutdown/Stop the cluster application gracefully by following all the required vendor best practices
• Shut down all VMs that are sharing the RDM disks (First shutdown all the secondary/passive VMs and then primary VM)
• Remove shared RDMs from the secondary VMs (choose Remove from VM only)
• Then remove the RDM from Primary VM (choose Remove from VM only select delete from disk (It will not delete the data but it will remove the pointer file))
• Migrate both VMs to destination datastore 
• Attach the RDM to Primary VM. (Please pay attention to do that reflecting same SCSI number and ID to which every Disk is connected as noted in the Precheck)
• Attach the disks to secondary VMs using add existing hard disk option. (Please pay attention to do that reflecting same SCSI number and ID to which every Disk is connected as noted in the Precheck)
• Power On the VMs starting with Primary/Active Node before powering on the secondary/passive.