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storage pool large array configuration - which way is better? RRS feed

  • Question

  • We built a backup server for a client to use for DPM that contains (36) 2TB SAS drives. The OS is installed on its own internal mirrored array and not part of the 36 drive hot-swappable pool. We are backing up approximately 25-30 servers. We are trying to plan for the best way to configure the 36 drives to present them to DPM. We have already read that the Dev team recommends a maximum of 17TB per GPT. This particular hardware configuration requires us, at a minimum, to create two RAID arrays due to a limitiation of the number of devices allowed in a single array. So i figured we would create (2) RAID 5 arrays. One with (24) 2TB drives and the other with (12) 2TB drives...this is primarily based on the backplane layout and connections to the RAID controller. This was our original plan but then i started thinking it may be better to just create a bunch of (2) drive RAID 0 arrays. Certainly i understand that i would be giving up the redundancy of the RAID 5 configuration, but by isolating the storage container groups into multiple 4TB RAID 0 arrays i actually increase the overall availability of the backup solution since a drive failure would only affect that one container group but would leave all others intact. In the case of a RAID 0 failure, the backup could then be reconfigured to another container group until that array was repaired. A side benefit is that I would also gain an additional 4TB of storage that would be normally lost by creating the (2) RAID 5 arrays.

    Am i completely missing the boat or is this a valid and beneficial configuration? I am completely new to DPM so its very possible that my design is fundamentally flawed as well...

    Looking for any thoughts or feedback...thanks.


    Kenneth Pergeorelis
    Friday, May 20, 2011 5:35 AM

Answers

  • Closing post - controller restrictions make it impossible to comply with 17TB maximum disk size.  Raid-0 has known risks.
    Regards, Mike J. [MSFT] This posting is provided "AS IS" with no warranties, and confers no rights.
    Saturday, October 29, 2011 3:54 PM
    Moderator