I need to move a single VM from tenant A to tenant B. Tenant A has an active subscription with several other services that must remain there, so I only want to migrate this VM and its disks to a new subscription or resource group in tenant B. What migration approach would be safest and most practical?
3 Answers
A backup and replication product such as Veeam can handle the migration, but it may be more expensive than using snapshots, SAS URLs, and scripted disk copies for a one-time transfer.
For smaller disks, you can export them with Azure Storage Explorer, upload them to the destination tenant, and create a new VM using the uploaded disks. Storage Explorer can also copy the disks directly between storage locations, which is usually preferable to downloading everything to a local machine.
For a large VM, a practical approach is to use a temporary “swing” subscription that can be moved between tenants. First, make sure the required permissions are configured. Delete the VM while retaining its managed disks, create snapshots of those disks in the temporary subscription, move that subscription to tenant B, and then create new disks from the snapshots in the destination subscription or resource group. Finally, recreate the VM using those disks. The process takes some setup, but it can be scripted and avoids downloading many terabytes locally.
You may not need a separate subscription if you can generate a SAS URL for the snapshot and use AzCopy or Azure Storage blob copy to transfer it directly into the destination tenant.
That makes sense. I’ll compare the cost and complexity against the snapshot-copy approach.