Retiring a storage pool disk: How to consolidate and migrate data? RRS feed

  • Question


    Above is an excellent article on using the MigrateDatasourceDataFromDPM.ps1 powershell script, and this procedure works very well for migrating all data from a disk to a new empty disk.

    I've got a disk with only 15 percent utilization and many other disks of the same size with over 25 percent free space on them.   Since I have an abundance of space, I want to migrate the data from the 15 percent utilized disk to one (or multiple) others.  Since DPM stores chunks of disk space in a non-contiguous way on the disk, the MigrateDatasourceDataFromDPM.ps1 script failed, however it now fully allocated the volume I was trying to move data to, worsening my situation and taking up more space.

    Right now, since this script has made a huge mess - I think the best solution would be to take my disk that only has 15 percent utilization and somehow mark it read-only so DPM no longer writes new data to it and let the data naturally expire out.

    I cannot find a powershell command or script that allows me to do this, so my question is, how can this safely be done?  I don't want any new data written to this one particular disk, however I want recovery points that are currently on it to expire out according to their normal schedule.

    Any help would be greatly appreciated!



    Wednesday, February 4, 2015 6:26 PM


All replies

  • Hi,

    you have missed something very important in the blogpost you mentioned

    The MigrateDatasourceDataFromDPM script moves all data for a data source or disk to the new volume or physical disk. After migration is complete, the original disk from where the data was migrated from is not chosen for hosting any NEW backups, however the recovery points located on the source disk can be used for restores until the recovery points are expired.

    So, the script will note move anything, only telling SCDPM that all new Recoverypoints should be created at the new Disk. And thats the only way

    You need to wait, until the old RP on the old Disk are expired to free up the Space.

    You can use this Script to Migrate Datasource:

    Seidl Michael | | | |

    Wednesday, February 4, 2015 8:10 PM
  • Michael, thanks for the quick reply!  Apologies, I should have clarified - since the powershell script cannot find a contiguous block of free space (even though total free space on the destination volume is greater than the amount that needs to be moved from the source volume), the script isn't fully finishing.  

    I jumped to the assumption that since the disk in question 1.) still shows up in the storage pool UI and 2.) none of the protection groups show any consistency differences, that the script hasn't actually migrated the backup targets to the alternate volume specified.   Since no one volume appears to have a large enough contiguous block to allocate, what I was wondering was if there was a way to just mark this one to not receive any new recovery points without having to specifically specify another volume. 

    I understand that the script will not move existing data and recovery points off and that I will have to wait for them to expire, my issue is that the script needs to pre-allocate the space somewhere, and even though I have an abundance of it, there is no one single volume that has a large enough contiguous block for this script to complete successfully.
    Wednesday, February 4, 2015 9:05 PM
  • I tried this migration again, this time with a test disk I had some space on (disk9).   Disk 10 is the one I am trying to migrate.   I followed the steps of the article exactly, and also verified that my variable $disk[disknumber] was correct and pointing to the correct source and destination disks before executing. 

    I still ran into an issue where it claimed I did not have enough space.   Disk 10 in the screenshot below is the source disk, it contains less than 500GB of data in a bunch of small chunks.   Why is the script creating these huge volumes on my destination disk?  More importantly, nothing was removed from the storage pool as the article describes, nothing shows consistency errors after the check either.   Is it safe to assume that the script failed and I can delete these volumes on Disk 9 without causing major issues?  How would I know?  And also, I'm still stuck with this data on Disk10 that is still being written to.  I need to find a way to remove this from the pool so I can eventually expire out the recovery points and retire the disk.

    If anyone has any advice on how to go about tackling this odd issue, it is greatly appreciated!

    Many thanks,


    Friday, February 6, 2015 8:06 PM
  • Here's another screenshot showing the correct disks in each variable:

    Friday, February 6, 2015 8:13 PM
  • Hi please try the Script i mentioned, there are some ways to Migrate only DS, or free a disk, should work

    Seidl Michael | | | |

    • Marked as answer by Nick Dantonio Tuesday, February 10, 2015 5:06 PM
    Monday, February 9, 2015 10:02 AM
  • Many thanks! Migration of individual DPM data sources works great in your script!    Apologies - I had thought you had originally re-linked the built in MigrateDataSourceDataFromDPM.ps1 and I accidentally overlooked your script.  

    Thanks again,


    Tuesday, February 10, 2015 5:09 PM