DPM 2016 - Large Modern Backup Storage with ReFS, but default Virtual Disk size is only max 16TB? RRS feed

  • Question

  • Hello,

    We use DPM 2016 on Windows 2016 Server with Modern Backup Storage (MBS). Our backup disk is formatted as ReFS, is about 37TB and we have about 17TB of free space left.

    DPM correctly sees this disk and allocates replica space for all our Protection Groups automatically. When allocated space runs out, DPM automatically allocates more space to the Protection Group. We recently ran into a problem that the allocated space for our Archive protection group wasn't automatically expanding anymore, failing our backup synchronizations. The size of 1the 1 disk in the Protection Group is about 14.5GB now.

    After consulting http:"" we tried to manually increase the allocation space, but this resulted in unclear StorageManager ID: 40001 errors.

    After looking in Disk Manager what DPM tries to do it looks like it assigns NTFS formatted Virtual Disks to a disk in a protection group, which then is stored on the MBS disk. Only it looks like DPM automatically creates a 4KB cluster NTFS Virtual disk which only goes up to 16TB...

    Can someone confirm that this is true? Is this why automatic grow fails? And what if I want to extend my file disk data beyond 16TB? Can I tell DPM not to use 4KB cluster NTFS formatted disks?

    Thanks in advance!

    Kind regards,


    Friday, April 20, 2018 10:42 AM

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