I need to migrate a single VM from tenant A to tenant B. Tenant A has an active subscription with several other services, but only this VM needs to move to a new tenant and subscription. What migration approach would you recommend, especially for preserving the VM's disks and avoiding unnecessary downtime or data transfers?
3 Answers
A backup and replication product such as Veeam can also handle the migration, but it may be more expensive than using snapshots, SAS-based copying, or a temporary subscription, especially for a one-time move.
For a large VM, a practical approach is to use a temporary “swing” subscription. Give it the permissions needed to move between tenants, delete the VM while retaining its managed disks, create snapshots of those disks in the swing subscription, move that subscription to the destination tenant, and then create new disks and a VM from the snapshots. It takes some setup, but the process can be scripted and avoids downloading many terabytes of data.
You may be able to skip the extra subscription by generating a SAS URL for the snapshot and using AzCopy or an Azure Storage blob copy operation from the destination tenant.
For a smaller VM, you can export or copy the disks with Azure Storage Explorer, upload them into the destination tenant, and then create a new VM using the existing disks. This is straightforward, but transferring large disks over a local connection can take a long time.
A direct disk copy through Storage Explorer is another option worth testing if the disk size and available transfer bandwidth make it practical.
This same subscription-transfer method can work for other Azure resources too, including very large storage accounts where downtime and downloading the data aren’t realistic.