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dhuygelaere's avatar
10 years ago
Solved

BE 2015 FP3 and hyper-v 2012 R2

Hi all,

I've an issue with be 2015 FP3 and hyper-v 2012 R2.Full backup of hyper-v host with 2 VM (2012 R2) completed successfully, but checkpoint are not removed, so nexts backup  failed. Individual backup of VM are correct, and checkpoint deleted. Any idea ?

  • OK as based on the results I have seen on test (Against Hyper-V 2012 R2)

    The new/faster method will merge the older checkpoint into the VHDX file and only keep the newer checkpoint file (AVHDX) at the end of each backup. This checkpoint file will then exist until the end of the next backup when it itself is merged into the vhdx.  So when using this method (apart from the first ever full backup), during a backup job 2 checkpoints and 2 AVHDX files will be seen however at the end of the job only the later checkpoint (avhdx file) will remain. As such, as long as regular backups are run, the checkpoint file will not keep growing as the original machine state  (vhdx file) is still updated/merged/committed into regularly. Note: The new/faster method backup will create this checkpoint as the full job runs irrespective of whether only full jobs will be run.

    If NO faster method backup jobs have been run and the old/standard method backup is run, this does not leave a checkpoint (or AVHDX file) present when jobs are NOT running but does create a checkpoint (briefly) and an avhdx file during backup operation which is merged into the machine state (vhdx file) at the end.

    If changing from running the faster method back to the standard method a checkpoint (avhdx file) will be left in place if the powershell command of  Get-VMSnapshot -VMName 'VM' -ComputerName 'HOST' | Remove-VMSnapshot  has NOT been used when making the change. This checkpoint (AVHDX file) becomes the object that gets updated with the original machine state (VHDX files) remaining untouched and therefore the AVHDX file will grow but the vhdx file will no longer be modified - As this is potentially undesirable behaviour, if doing this change the Powershell command should be used.

    If using the faster method and you see more than 1 Backup Checkpoint,  when a job is not running (or more than 2 Backup Checkpoints, when a job is running) then something, outside of Backup Exec's direct control, blocked the removal of an earlier checkpoint and you should review the Hyper-V-VMMS  event log (Event Viewer —> Applications and Services Logs —> Microsoft —> Windows —> Hyper-V-VMMS —> Admin) for errors. Also if this condition is experienced, be prepared to use the powershell command to remove the checkpoints to tidy up. If this is a regular problem and/or the powershell command fails to tidy up the snapshot then Microsoft should be involved to help understand and identify why the checkpoint(s) cannot be removed. Note: the first time a faster method full backup takes place then it is expected to see event ids  15070 and 10155  against unable to remove a checkpoint

     

    Note:

    At various points in time, whilst backup jobs are active,  AutoRecovery Checkpoints (avhdx files) are also created but these are always removed before the job finishes.

    Also no matter whether running standard or faster method jobs “ Backing up”, “Merge in Progress” and “Creating  Checkpoint” statuses can  seen in the Hyper-V  manager against the VM.

     

    EDIT MADE AFTER THIS POST WAS MARKED AS A SOLUTION:

    A technote has been created to explain this and to give a variation on the Powershell Command to allow removal of the backup checkpoints and not all of the checkpoints - added to this post just to give te most up to date into in the solution post

    http://www.veritas.com/docs/000100786