Converting to Azure Stack Hub

When restoring a virtual machine from backup, you can choose to restore the VM as an Azure Stack Hub VM.

You can use this feature to migrate virtual machines to Azure Stack Hub.

Source Hypervisors

You can convert VMs to Azure Stack Hub from the following hypervisors:

  • Azure Resource Manager

  • Hyper-V

Conversion is not supported from IntelliSnap snap copies.

Before You Begin

  • Before performing backups of source VMs, check whether the source VMs meet the following requirements:

    • Remote Desktop Protocol (RDP) must be enabled on the source VM and the user performing the conversion must be able to log on to the VM.

    • For Linux VMs being converted from Hyper-V, Hyper-V integration services must be enabled on the source VMs if they will be powered on automatically after conversion.

    • Static network connections are not configured as part of conversion. If a virtual machine is configured to use a static IP address, change the network configuration to use DHCP before performing the backup.

    • For conversion from Hyper-V differential disks or checkpoints of virtual machines (files with .avhd or .avhdx extensions) will not be uploaded to Azure Stack Hub. Merge such disks to the original disk before performing the backup.

  • Azure Stack Hub Standard or Premium general-purpose storage accounts are required for VM conversion to Azure Stack Hub.

  • To enable deployment in Azure Stack Hub, define one or more resource groups for the application associated with the Azure Stack Hub hypervisor.

  • Configure backups for Azure Stack Hub.

  • When restoring an Azure virtual machine, do the following:

    • For Windows computers: enable the pagefile on the C: drive of the source VM. This will prevent you from receiving an error message when you reboot the destination VM.

    • For Linux computers : Ensure that the fstab entry of the source disk should be based on disk UUID and not disk name. If it is not based on disk UUID, then the restored VM will not boot up.

  • For information about the restore options for the Azure Stack Hub destination, see Options for Conversion to Azure Stack Hub.

  • The operating system for the destination VM must be an operating system that is supported for Azure.

  • Conversion of generation 2 virtual machines is not supported.

Commvault Considerations

  • Use a Windows access node to restore a VM to Azure Stack Hub.

    Conversion is not supported when you use a Linux access node.

  • For Hyper-V source VMs, converting VHDX formatted 4K sectored disks to Azure Stack Hub is not supported.

  • If the Auto Select option is selected and the disk operating system type cannot be determined from the configuration file, the job will fail. You can resubmit the job by selecting the proper operating system in the Restore options dialog box.

  • The Power on VMs after restore option is selected by default. If this option is not selected when the VM is restored, only the operating system disk is registered, and any remaining disks are uploaded to the Azure Stack Hub storage account. In this case, you must recreate the VHDs manually through the Azure Stack Hub management portal by using the Create VHD option on the Disk tab:

    1. For each disk, browse to the storage location and open the disk from which the VHD is to be created. Opening the disk registers it as a VHD so that it can be attached to a new or existing VM.

    2. Select the VM to which the VHD is to be attached, and attach one or more registered VHDs from the storage location.

Azure Stack Hub VM Considerations

  • The VM name can only contain alphanumeric characters or the '-' character; the name cannot contain any Unicode Transformation Format (UTF) characters.

  • Conversion is not supported for virtual machines that use Extensible Firmware Interface (EFI) boot methods.

  • Before you convert a VM from a non-Azure hypervisor using a "restore as" operation, verify that the source VM meets the requirements for non-endorsed distributions. This verification is important because Linux VMs that are based on an endorsed distribution of Azure have the prerequisites that enable them to run on Azure, but VMs that originate from other hypervisors might not. For more information, see Information for Non-Endorsed Distributions.

  • The RAM and disk specification for the source VM must match the format of the Azure Stack Hub destination VM. For example, if the source VM RAM is less than 1.75 GB and AUTO is selected as the VM size for the conversion, only two disks will be uploaded, because of Azure Stack Hub restrictions.

  • To manage storage and associated costs, for Azure Stack Hub managed disks, you can specify a disk type (Standard HDD or Premium SSD) for the Azure Stack Hub destination VM.


    If the size of the destination VM does not support the Premium SSD disk type, the VM is deployed with the Standard HDD disk type.


  1. From the Command Center navigation pane, go to Protect > Virtualization.

    The Virtual machines page appears.

  2. Click the VM groups tab.

    The VM group page appears. The VM groups area displays summary information for any existing VM groups.

  3. In the VM groups area, click Restore for the VM group that contains the virtual machine.

  4. In the Select restore type page, select Full virtual machine to restore one or more full virtual machines.

  5. In the Restore page, expand the tree on the left and select the objects to be restored on the right. Select an item or click on an entry in the Name column to browse within an item.

    In the top right corner of the page, a "Showing" message indicates what backup data is being displayed. You can click the down arrow beside this message and select any of the following options:

    • Show latest backups: Only display data for the most recent backups.

    • Show backups as of a specific date: Only display data up to the date you specify.

    • Show backups for a date range: Only display data within the data range you specify.

    The Restore options dialog box appears.

  6. Enter the restore options for the Azure Stack Hub VM.

  7. Click Submit to run the restore job.


If the source VM had dynamic disks that use simple disk spanning, RAID, striped, or mirrored layouts, after VM conversion, the disks in the converted VM might be marked as Failed in Disk Management. You must bring these disks online manually using Disk Management. To bring the disks back online, perform an Import Foreign Disks operation on the guest VM for the disk group that contains failed disks. Import the entire disk group in one operation rather than performing a partial import.