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MFT Errors in DPM space allocations (Causing Problems) - DPM 2007 RRS feed

  • Question

  • Hello,
    I'm having problems with MFT tables for the DPM space allocations that are located on a Fiber attached SAN. I use a couple of HP MSA2000 fiber attached storage devices.
    (Basically these: http://h18000.www1.hp.com/products/quickspecs/13045_div/13045_div.html)

    Yesterday all of the drives "disappeared" from DPM and DPM reported: "Volume Missing" for just about every space allocation in the DPM console. I powered off the server completely powered down the SAN's completely powered on the SAN's and brought the server back online. Opened DPM and to my discouragement found that the same error was occuring again. "Volume Missing" for every allocation.

    I logged into the MSA2000 web interface to investigate the RAID arrays (6 x RAID 10 configurations = ~12TB of space available to DPM)

    All of the arrays are healthy. There are no errors on the HP SAN whatsoever.

    I can see all of the drives in the Management area of DPM and in disk management (Even when these "Volume Missing" errors were occuring. The drives were all visible and all of them look healthy. But DPM was still displaying "Volume Missing"

    A third party monitoring tool we use picked up this error this morning:

    Cause: This behavior can occur if the NTFS volumes Master File Table (MFT) is corrupted. The short and long file name pairs that are stored in the directory index record and the file names that are stored in the associated File Record Segment (FRS) contain case-sensitive characters that do not match.

    So the MFT's in the (160+ space allocations on the server (Who knows which ones off-hand)) on the SAN's might be in need of repair.

    Here lies the problem. How do you run a chkdsk to fix problems on hundreds of "Space allocations" that do not have drive letters? There is evidently a problem here and I don't want my backups to completely fail.

    I did temporarily fix this (By freak chance) when I went into the Management section > Disks of the DPM administrator console right-click the drives that were visible for storage and click "Rescan" DPM mysteriously realized the drives were available (How it didn't already know this I have no idea) and then all of a sudden the "Volume Missing" errors went away. Backups succeeded this morning.

    Ultimately the problem is still "How do I fix errors with CHKDSK on volumes that are not mounted, how do I isolate the problem volumes, and how do I prevent errors with these disk allocations that are not assigned drive letters?"

    Thanks for any tips or guidance you can provide on this matter in advance!

    Tuesday, August 28, 2012 5:23 PM

All replies

  • Backups succeeded today as well. But the question still remains how to run a chkdsk / file system / MFT repair method on these volumes if they do not have drive letters assigned to the volumes. Any ideas folks? Just trying to figure out how DPM keeps the volumes it allocates for backups healthy when there are file system / MFT errors encountered.
    Wednesday, August 29, 2012 4:14 PM
  • running chkdsk on your volumes can cause corruption and problems for you. You might have to trash the volumes and recreate them.
    Wednesday, August 29, 2012 5:25 PM