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Snapshots that don't exist RRS feed

  • Question

  • Hello

    I think I have a unique situation whereby my virtual machine XML file says there are 3 snapshots.

    However, within HyperV gui there are NO snapshots present. I think this has occured due to a VHD restore from DPM but did not restore the XML file.   There are however snapshot files on the physical drive but the guids don't match the XML file anyway.

    Am I safe to delete the rogue snapshot files and what should I do about the XML snapshot entries?

    here is the current live XML file - again, the GUI shows NO snapshots.

    <disk_merge_pending type="bool">False</disk_merge_pending>
        <owner>
          <sid type="string">xxxxxxxxxxx</sid>
        </owner>
        <power>
          <host_shutdown>
            <action type="integer">1</action>
          </host_shutdown>
          <host_startup>
            <action type="integer">1</action>
            <delay type="integer">0</delay>
          </host_startup>
        </power>
        <security>
          <scope type="string">xxxxxxxxxxxxx</scope>
        </security>
        <snapshots>
          <data_root type="string">E:\xxxxxxxxxx\Snapshots\</data_root>
          <list>
            <node0>
              <guid type="string">04773C63-EB00-4023-A78C-5D87708D94F0</guid>
            </node0>
            <node1>
              <guid type="string">D3A605A9-973B-4B34-8250-DB1D2F3D27D2</guid>
            </node1>
            <node2>
              <guid type="string">DECB605F-FABA-4862-84B5-4C846C56F115</guid>
            </node2>
            <size type="integer">0</size>

    Wednesday, November 28, 2012 1:46 PM

Answers

  • Most folks get into this problem because the snapshots are deleted (thus removed from the GUI) but the VM has not been powered off to allow the AVHD files to be merged into the VHD files.

    If you check your Hyper-V Event logs under Applications and Services in the Event Viewer you might find pending merges or merges that are failing for some reason.

    http://itproctology.blogspot.com/search/label/snapshot


    Brian Ehlert
    http://ITProctology.blogspot.com
    Learn. Apply. Repeat.
    Disclaimer: Attempting change is of your own free will.

    • Marked as answer by Lawrence, Friday, December 7, 2012 8:45 AM
    Wednesday, November 28, 2012 4:34 PM
  • export/import agreed. As long as you are not performing any reverts etc.

    Also have a read here on the virtual domain controller:
    How to configure your virtual Domain Controllers and avoid simple mistakes with resulting big problems
    http://www.sole.dk/how-to-configure-your-virtual-domain-controllers-and-avoid-simple-mistakes-with-resulting-big-problems/

    • Marked as answer by Lawrence, Friday, December 7, 2012 8:45 AM
    Monday, December 3, 2012 11:56 AM

All replies

  • Most folks get into this problem because the snapshots are deleted (thus removed from the GUI) but the VM has not been powered off to allow the AVHD files to be merged into the VHD files.

    If you check your Hyper-V Event logs under Applications and Services in the Event Viewer you might find pending merges or merges that are failing for some reason.

    http://itproctology.blogspot.com/search/label/snapshot


    Brian Ehlert
    http://ITProctology.blogspot.com
    Learn. Apply. Repeat.
    Disclaimer: Attempting change is of your own free will.

    • Marked as answer by Lawrence, Friday, December 7, 2012 8:45 AM
    Wednesday, November 28, 2012 4:34 PM
  • There is only 1 avhd file but the XML above lists three guid's ??
    Wednesday, November 28, 2012 4:40 PM
  • There should be no need to manually modify the snapshot entries in the XML file, let the system manage it.

    Also, since this was a restore, the snapshot files might actually be in use as part of a chain.

    In restore situations this is always a mess.

    The three GUIDs should reference Folders.  The folders represent the moments in time, and the configurations at that time (so many GUIDs, so little time).

    The AVHD files are simply the disk state.

    If you are concerned and want it all neat and tidy, and have 2008 R2 +, then take a snapshot and export that snapshot to a new VM.  Import that snapshot, test it, delete the original (messy) one.


    Brian Ehlert
    http://ITProctology.blogspot.com
    Learn. Apply. Repeat.
    Disclaimer: Attempting change is of your own free will.

    Wednesday, November 28, 2012 5:21 PM
  • If you are concerned and want it all neat and tidy, and have 2008 R2 +, then take a snapshot and export that snapshot to a new VM.  Import that snapshot, test it, delete the original (messy) one.


    Brian Ehlert

    Hi Brian

    I am starting to think this is the only way to get out of this mess

    If I follow this procedure, will I encounter a USN Rollback on the domain controller?

    1. Verify replication is up to date and shutdown the virtual domain controller

    2. Quickly take a snapshot before VHD merge starts taking place (will a snapshot override a merge process?)

    3. Export the snapshot to external drive

    4. Delete original VM from HyperV

    5. Move old VHDs elsewhere

    6. Import exported file and specify "move and keep old GUID" location = original location (providing step 5 works)

    How long should this process take for a 60GB vm to external USB?

    Thanks

    Thursday, November 29, 2012 10:04 AM
  • Hiya,

    When you inspect your disk from HyperV Manager what type is it listed as?

    Thursday, November 29, 2012 11:51 AM
  • Hiya,

    When you inspect your disk from HyperV Manager what type is it listed as?

    It is a differencing disk which has one link to a dynamically expanding parent disk.

    Thursday, November 29, 2012 11:52 AM
  • Then you definitely cant delete in the XML. I'm pretty sure the problem is, as BrianEH states, a missing merge.

    You mention Domain Controller, is the target server DC?

    Thursday, November 29, 2012 12:03 PM
  • Then you definitely cant delete in the XML. I'm pretty sure the problem is, as BrianEH states, a missing merge.

    You mention Domain Controller, is the target server DC?

    Yes domain controller, holding fsmo roles and dhcp!

    My other post is about the 2nd domain controller!

    I think the export/import is the way to go and have a system state/bare metal backup as a backup....

    Thursday, November 29, 2012 12:05 PM
  • export/import agreed. As long as you are not performing any reverts etc.

    Also have a read here on the virtual domain controller:
    How to configure your virtual Domain Controllers and avoid simple mistakes with resulting big problems
    http://www.sole.dk/how-to-configure-your-virtual-domain-controllers-and-avoid-simple-mistakes-with-resulting-big-problems/

    • Marked as answer by Lawrence, Friday, December 7, 2012 8:45 AM
    Monday, December 3, 2012 11:56 AM