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Unable to complete a backup when a single data source is bigger than 1 tape RRS feed

  • Question

  • One of our data sources has grown to the size that it is larger than will fit on a single LTO-5 tape. DPM is now unable to complete the backup. After prompting for a new tape which is then provided, it writes as much as will fit (~1.65TB) to the tape, then requests another tape. When the "run tape backup job again" is selected (due to waiting for tape timing out), it appears to write from the start and the job never completes.

    When you select view tape contents of the partial tape, the warning message "DPM needs to recatalog the selected tape before it can display its contents. Do you want to recatalog the tape now?" comes up. Selecting Yes does absolutely nothing. Even after just doing an inventory of the library, it refuses to display the contents of the tape.

    Is there any way to get DPM to back up a single data source bigger than a single tape? If we upgrade to 2016 is this issue resolved?

    Saturday, November 19, 2016 12:07 AM

All replies

  • Hi,


     During a tape backup if a tape becomes full and there are no other tapes marked free, Free (contains data) or expired in the library - or if you are using a standalone tape drive that needs you to manually change the tape, DPM will raise an alert to prompt for another free tape to continue backup.  The same is true during a restore, if a needed tape is not in the library an alert will be raised.  By Default, DPM It will wait for 1 hour before failing the job.

    This prompting timeout can be configured by the registry entry "PromptingTimeOut" under "HKLM\Software\Microsoft\Microsoft Data Protection Manager\1.0\Prompting"

    PromptingTimeOut:REG_Dword:43200000 (dec) = 12hrs

    The Formula is   (#hrs * 1000 * 60 * 60)
    1HR =  1*1000*60*60 =  3600000  decimal


    =-=-=Value is in milliseconds=-=-=
    3600000 = 1 hour
    43200000 = 12 hours
    86400000 = 24 hours
    129600000 = 36 hours
    172800000 = 48 hours

    Restart the DPMRA service.


    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.

    Wednesday, November 23, 2016 9:37 PM
    Moderator
  • We are using a standalone drive which needs the tape to be changed manually.

    Just to clarify, if the job is allowed to "continue" after inserting a fresh tape, is that different from DPM's perspective, of letting the job fail and then clicking "Run tape backup job again?"

    Thursday, November 24, 2016 12:43 AM
  • Hi,

    Yes, a big difference.  As noted, once a tape job fails if you click on the "Run tape backup job again" that will start over from the beginning because after the timeout DPM discarded the partial backup since it could not continue.  The only way to get a good backup is to insert a free tape prior to the timeout period so the backup can continue and complete.


    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, November 28, 2016 4:14 PM
    Moderator