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migrating data from DPM disk to another RRS feed

  • Question

  • Hi. There was a need to remove a disk from DPM, so I've added new disk and ran the MigrateDatasourceDataFromDPM.ps1 script. This ran successfully.

    But since we were in a hurry, I wanted to speed this up and not wait until all the existing recovery points on that disk expire. I've noticed that there were only some BMR backups left on that disk (at least that's what the Management - Disks pane reports says), so I've removed those BMR backups (stopped the protection and deleted the data), then waited a bit and reconfigured the BMR protection. I was expecting the data to be stored on different different disks, but they ended on this to-be-removed disk again.

    How is this possible when the disk should be excluded from data placement once the script runs and finishes?

    My second point - judging from windows disk management, there is obviously other data (besides the BMR backups) still protected on this source disk (the recovery points that haven't expired yet I presume). Why aren't these reported in the DPM Management - Disks pane???

    Thanks in advance


    Monday, May 11, 2015 7:00 AM

Answers

  • Hi,

    <snip>
    "After migration is complete, the original disk from where the data was migrated from is not chosen for hosting any NEW backups"
    >snip<

    The above statement is true for "successful" migrations.  If a migration fails (as it did for you) and one or more data sources were not migrated, then the disk is not removed from the DPM storage pool and can continue to be used as needed.


    Please remember to click “Mark as Answer” on the post that helps you, and to click “Unmark as Answer” if a marked post does not actually answer your question. This can be beneficial to other community members reading the thread. Regards, Mike J. [MSFT] This posting is provided "AS IS" with no warranties, and confers no rights.

    Tuesday, May 19, 2015 8:55 PM

All replies

  • Hi,

    The migrated disk will only be removed from the DPM Storage pool if the migration completed successfully.  You said that some BMR data sources were still on that disk and you manually deleted them, but that action will not remove the disk from the storage pool.  As long at the disk is in the DPM storage pool it is a candidate to be used when extending existing volumes or for new volumes when adding new protection.

    To summarize:

    1) Use the MigrateDatasourceDataFromDPM.ps1 script to migrate a disk.
    2) If some data sources did not migrate (for whatever reason) and you decide to stop protection and delete replica, make sure no data sources are listed when highlighting that disk in the DPM Storage pool.
    3) When the disk shows no data source - remove the disk from the DPM Storage pool using DPM GUI.
    4) If you don't want to wait for old recovery point to expire before physically removing the migrated disk from the system, you can either reduce retention range for the PG that the migrated data source belong to or run the powershell script located in this forum post to expire recovery points early on a datasource by datasource case.


    Please remember to click “Mark as Answer” on the post that helps you, and to click “Unmark as Answer” if a marked post does not actually answer your question. This can be beneficial to other community members reading the thread. Regards, Mike J. [MSFT] This posting is provided "AS IS" with no warranties, and confers no rights.


    Monday, May 11, 2015 6:59 PM
  • Again, the undesired practice of these forums where mods mark replies as answers before the OP does.

    Anyway, thanks for the reply Mike, I haven't had the chance to try that procedure yet, once I get to it, I'll update this thread.

    Monday, May 18, 2015 7:29 AM
  • I couldn't proceed with the above outlined procedure, because there are thousands of RPs and finding the ones that reside on the disk we wanted to remove and then expire them early on would be very time-consuming.

    In the end, I forcibly disconnected the disk simulating a failure and then used dpmsync.exe -reallocatereplicas to move the replicas, then manually forced consistency check on the protected sources that got market for the manual synchronization. Also some protected recources had to be deleted and recreated since they wouldn't synch even with consistency check.

    I don't understand why MS makes such simple procedure so cumbersome ... replacing a HDD used by DPM (either failed one or as a planned procedure) is a regular operation.

    Btw. Mike, you said "As long at the disk is in the DPM storage pool it is a candidate to be used when extending existing volumes or for new volumes when adding new protection", but http://blogs.technet.com/b/askcore/archive/2009/06/22/how-to-use-the-migratedatasourcedatafromdpm-ps1-dpm-powershell-script-to-move-data.aspx says something different: "After migration is complete, the original disk from where the data was migrated from is not chosen for hosting any NEW backups"


    • Edited by MarkosP Tuesday, May 19, 2015 1:44 PM
    Tuesday, May 19, 2015 1:43 PM
  • Hi,

    <snip>
    "After migration is complete, the original disk from where the data was migrated from is not chosen for hosting any NEW backups"
    >snip<

    The above statement is true for "successful" migrations.  If a migration fails (as it did for you) and one or more data sources were not migrated, then the disk is not removed from the DPM storage pool and can continue to be used as needed.


    Please remember to click “Mark as Answer” on the post that helps you, and to click “Unmark as Answer” if a marked post does not actually answer your question. This can be beneficial to other community members reading the thread. Regards, Mike J. [MSFT] This posting is provided "AS IS" with no warranties, and confers no rights.

    Tuesday, May 19, 2015 8:55 PM