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J_Huggins's avatar
J_Huggins
Level 6
7 years ago

Hyper-V policy restore error (2821)

Hi all, Seeking for you help :(

Encountered the said issue just like on the subject. However we can open the restored virtual machine and all of the data are also restored. I am wondering why I am having this issue? What is the meaning of that? Since the restored Virtual Machine are running?

Setup: Hyper-V 1 with Virtual Machine and restored that VM on another Hyper-V which is our second Hyper-V. I think the restoration are successful but we encountered the said issue.

We are using NBU 7.6.0.4 (Master, Media and Client)

Kindly see attached photo to see the detailed status.

Thank you so much!

Regards, Jonas

  • Hi J_Huggins,

    I found this notes about Hyper-V restores, from Admin guide 7.6, can you check if some of these situatios can be applied to your case?? Is this restore a full restore right?

    Notes on full virtual machine restore

    ■ A backup of the full virtual machine can be restored only to Windows Server2008 or later with the Hyper-V role enabled.

    ■ By default, the NetBackup client on the Hyper-V server does not have Windows Administrator privileges. You can restore a full virtual machine from the NetBackup server. You cannot restore a full virtual machine from a NetBackup
    client that does not have Administrator privileges.

    ■ For the virtual machines that are configured in a volume GUID with a differencing disk in another volume GUID, redirected restores are not supported.

    ■ When you restore the virtual machine to its original location with the Overwrite virtual machine option, note: The same virtual machine on the Hyper-V server is automatically turned off and deleted before the restore. The .vhd or .vhdx files
    of the virtual machine on the Hyper-V server are overwritten by the .vhd or .vhdx files from the backup image. If any new .vhd or .vhdx files were created after the backup, those files are not removed.

    ■ When you restore the virtual machine to a different location on the original Hyper-V server or to a different server, note: The same virtual machine (if it exists) on the Hyper-V server is automatically turned off and deleted before the restore if you choose the Overwrite virtual machine option. The .vhd or .vhdx files of the deleted virtual machine, however, are not deleted. You must delete those files.

    ■ When you restore the virtual machine to a Hyper-V server that has a virtual machine of the same GUID, you must select the Overwrite virtual machine option. Otherwise, the restore fails.

    ■ If you restore a virtual machine without the Overwrite virtual machine option, note: You must remove the current virtual machine and its .vhd or .vhdx files from the destination server before you start the restore. If you remove the virtual
    machine but leave one or more of its .vhd or .vhdx files on the destination server, the .vhd or .vhdx files from the backup are not restored.

    ■ (This item is a limitation in VSS and the Hyper-V writer, not in NetBackup.) If the virtual machine contains Hyper-V snapshot files (.avhd or .avhdx files), NetBackup cannot restore the virtual machine to a different location or to a
    different Hyper-V server.

    Note the following:

    ■ This issue has been fixed in Windows Server 2008 R2 (restore server).

    ■ This restriction does not apply in either of the following cases: When you restore the virtual machine to its original location on the original Hyper-V server, or when you restore to a staging location. Note that NetBackup does not create Hyper-V snapshot files (.avhd or .avhdx).

    ■ (This item is a limitation in VSS, not in NetBackup.) Immediately after a full virtual machine is restored, the virtual machine volume may be larger than it was when the virtual machine was backed up. The increase is normal: After the restore, snapshot-related cache files remain on the volume. After about 20 minutes, the cache files are automatically removed and the volume returns to its original size

    Note: A new backup of the restored virtual machine could fail if the virtual machine volume contains insufficient space to create a snapshot for the backup. According to Microsoft, this situation should not occur as long as the virtual machine volume has at least 10 to 15% free space.

    ■ In the following case a race condition may result:

    ■ You attempt to do a full restore of two virtual machines at the same time.

    ■ The two virtual machines also share a virtual hard disk (.vhd or .vhdx file) that both restore jobs have selected to restore. The two jobs may simultaneously attempt to access the same .vhd or .vhdx file, but only one job gains access to the file. The other job is denied access, and that job may fail with error code 185.

    ■ If you restore a virtual machine to a different Hyper-V server, note: The original Hyper-V server and the target server must have the same number of network adapters (NICs). You must configure the network adapter(s) for the restored
    virtual machine on the target server.

    ■ Windows Hyper-V provides no mechanism for quiescing file system activity on Linux virtual machines. Therefore, at the time of backup, a snapshot of a Linux virtual machine may be in an inconsistent state (crash-consistent). Note that
    the backup succeeds. For restore of inconsistent Linux files from the backup, NetBackup creates a NetBackup.lost+found directory for each Linux volume.

     

    Regards,

     

    Thiago

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