We are migrating clustered applications like Oracle RAC from VMware to OpenShift Virtualization. These applications use shared volumes, i.e. the same VMDK disk is attached to multiple virtual machines at the same time.

Currently, when migrating clustered VMs, the MTV tool does not detect that the same volume is attached to multiple VMs. As a result, each VM migrated to OpenShift Virtualization receives its own copy of the originally shared volume. The shared volumes are typically very large (TBs of data). Making multiple copies takes hours and wastes network bandwidth. After the MTV completes the VMs migration, we have to re-create the shared volume in OpenShift by deleting all copies of the PVCs with the exception of a single copy which we then attach to all VMs in the cluster.

We would like MTV to be more smart when migrating VMs that use shared volumes. We include all these VMs in the same migration plan as we need to migrate all VMs belonging to the same application at once. 

We would like MTV to do the following (in increasing order of preference):

1. Review the VMs in the migration plan, detect if the same VMDKs are used by multiple VMs and display a warning that informs the user that the shared volumes will be duplicated.
2. Allow the user to pick the volumes that should be migrated (all by default) and that should be ignored. This would allow us to instruct MTV to migrate the shared volume only once which would greatly speed up the migration. We would re-attach the shared volume to other VMs manually after the migration is complete.
3. Ultimately, we would like MTV to automatically do the right thing: migrate the shared volume once and attach it to multiple VMs in OpenShift.