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DPM Backup to Tape Frustrations RRS feed

  • Question

  • Hi all,

    I am reasonably new to DPM 2012, and having some major frustrations with it's use, but wondered if these are due to limitations of the software or my mindset (coming from BackupExec).

    Firstly: Our client wants tape backups to be taken each night, to be sent offsite in a 4 week rotation period. They also want as much of the most recent data as possible kept on disk on-site (the backup server has ~8TB of storage, so this is more than possible).

    For the tapes to be successfully sent offsite, they need to have been written overnight and the tape-based backup completed by no later than 2pm the following day.

    Using Backup-to-Disk-to-Tape in DPM was what we attempted initially, but unfortunately this only allows for long-term backups to be written to tape (not incremental) which means that ~3.4TB of data needs to be written to tape each night. This is taking an extremely long time with only one tape drive in the library, and running past the 2pm time limit the next day. Additionally this means that when the tapes are returned as part of the rotation they have to be manually erased before they can be written to again.

    Next we tried running a backup directly to tape on a Friday night, and setting incrementals to run on each subsequent week day. But we have issues with this too. For some inexplicable reason, DPM just randomly decides to run a full backup on SOME (not all) nights that it should be running only an incremental (meaning it backs up 1TB of exchange data directly to tape on a week night, which is VERY slow).

    In addition to this, backing up directly to tape means that in order to ALSO retain a backup on disk, we would have two run TWO different protection groups containing the same servers, which is not possible in DPM, so how the hell are we supposed to do this?

    All we want is a short-term backup to be taken to disk, and that SAME backup then to be cloned to tape to be used in a 4-week tape rotation.

    Am I thinking about this the wrong way, or have I missed a configuration option somewhere or is DPM inherently flawed for this type of backup?

    Any help much appreciated!

    Rich

    EDIT: Side question. Is it possible that the reason that DPM is running a full backup mid-week because the previous nights incremental failed? And if so, I re-ran that incremental and it succeeded the second time, so why would this happen? Is it because I didn't clear the failure alert?


    • Edited by newbe5 Tuesday, September 3, 2013 11:45 AM
    Tuesday, September 3, 2013 10:15 AM

Answers

  • We have now resolved this. The reason it was running full backups to tape mid-week on a night that it should be running an incremental was due to a failed incremental backup the previous day. The frustration was that even if you re-ran the backup and it completed successfully on the second attempt, it would still be marked as failed and would STILL run a full backup to compensate. This was due to the failure messages still being present in the critical messages log. Marking that message as inactive prevents this behaviour from re-occurring.

    We are now happy that the backup-to-tape solution is working correctly, unfortunately the only way to also get this data on to disk is to run a long-term backup to dick AFTER the short-term tape backup, but we are leaving this behaviour out for now.

    DPM is unfortunately not ideal in mixed-media environments, but this is now working adequately for our needs.

    Richard

    • Marked as answer by newbe5 Monday, September 9, 2013 10:33 AM
    Monday, September 9, 2013 10:33 AM

All replies

  • Hi,

    <snip>
    Additionally this means that when the tapes are returned as part of the rotation they have to be manually erased before they can be written to again.
    <snip<

    If you have a retention period of 4 weeks and rotate the same set of tapes exactly every 4 weeks, then you need to be sure you are running KB2706783-Description of Update Rollup 2 for System Center 2012 or later then add this registry setting so DPM will overwrite tapes the same day they expire.


    Tapes are marked as reusable on the next day after the date of expiry as DPM runs a reclamation job only at midnight. If you want the tape to be reusable on the same date as it is expired, create the ExpireDatasetOnDayStart 32- bit DWORD, and set its value to 1 under the following registry key:

    HKEY_LOCAL_MACHINE\Software\Microsoft\Microsoft Data Protection Manager\Configuration\MediaManager


    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, September 3, 2013 8:35 PM
  • We have now resolved this. The reason it was running full backups to tape mid-week on a night that it should be running an incremental was due to a failed incremental backup the previous day. The frustration was that even if you re-ran the backup and it completed successfully on the second attempt, it would still be marked as failed and would STILL run a full backup to compensate. This was due to the failure messages still being present in the critical messages log. Marking that message as inactive prevents this behaviour from re-occurring.

    We are now happy that the backup-to-tape solution is working correctly, unfortunately the only way to also get this data on to disk is to run a long-term backup to dick AFTER the short-term tape backup, but we are leaving this behaviour out for now.

    DPM is unfortunately not ideal in mixed-media environments, but this is now working adequately for our needs.

    Richard

    • Marked as answer by newbe5 Monday, September 9, 2013 10:33 AM
    Monday, September 9, 2013 10:33 AM