DP2010 reserves a lot of space on protection group allocation RRS feed

  • Question

  • Hi,

    is there any way we can reduce disk allocation on dpm2010 backup because Allocated space is high on protection group  but actual utilized space is less .









    • Edited by IT2012 Wednesday, October 19, 2011 8:30 AM
    Wednesday, October 19, 2011 8:28 AM


All replies

  • Hi,

    You can use DPM console, right click and modify disk allocation on protection group.

    laiys Check out my blog
    Wednesday, October 19, 2011 11:05 AM
  • Hi,

    This please we can only increase the disk space allocation but this will not allow you decrease.


    Is there any  other we can use this?



    Tuesday, October 25, 2011 6:54 AM
  • Hi,

    According to here:_, you cannot decrease the allocation size.

    However another forum mentioned about the solution. Pls refer to


    laiys Check out my blog
    Thursday, October 27, 2011 6:19 AM
  • The default Hyper-V Co-located replica volume that DPM creates by default is 250GB meaning we will co-locate as many Hyper-V guests that fit on that 250GB volume up to 8 before we create another 250GB volume.

    You can modify the disk allocation for the Hyper-V guest data sources to make more efficient use of the volumes. Co-location is controlled at the Protection Group level since that controls the frequency and retenion range of the recovery points on those volumes.  You will need to delete the existing data and recreated the protection group to take advantage of this feature.

    Depending on your average Hyper-V guest, you can modify that registry key so you can take better advantage of the co-location feature.

    Key name: HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Microsoft Data Protection Manager\Collocation\HyperV
    Valuename= CollocatedReplicaSize and should be a multiple of 1GB (1073741824 bytes)

    Now, for you to do this, you would need to perform the following steps.

    1) Calculate the average size HyperV guest under protection, and plan for some growth over time.
    2) Multiply the (average size + growth) * 8 – this will be the new collocatedreplicaSize – make sure it’s a multiple of 1GB (1073741824 bytes)
    3) Modify the registry key to make it that new value.
    4) Unprotect the Hyper-V guests that are not co-located and chose the option to delete the replica volumes (yes that will remove all your backups, but the only way to get them on co-located replicas) - , be sure that you UNCHECK the option to delete tape recover points unless you want to expire them also.
    5) Re-protect the Hyper-V Guests, make sure the enable co-location checkbox is checked.
    6) DPM will make new larger replica volumes and co-locate up to 8 Guests per replica.


    Regards, Michael V. [MSFT] This posting is provided "AS IS" with no warranties, and confers no rights.

    Friday, October 28, 2011 9:56 PM


    Is there any way we can increase the number of guests per replica?






    • Edited by IT2012 Monday, October 31, 2011 12:41 PM
    Monday, October 31, 2011 12:41 PM
  • any help!
    Tuesday, November 8, 2011 10:53 AM
  • You can increase the number of guests per replica using the following registry key.


    Key Name: HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Microsoft Data Protection Manager\Collocation\HyperV

    ValueName= DSCollocationFactor  - this is the number of guests to co-locate per replica - default is 8

    Friday, November 11, 2011 10:15 PM