none
Restore/Move DPM to new server with reattached SAN drives containing replicas. RRS feed

  • Question

  • Having bit of a task ahead of me and need some advice.

    The setup: Four DPM servers (2012 SP1), a total of approx. 300TB of disks attached, some used for storage pool, some for Firestreamer VTL. Also there is a tape library attached. Data is coming in across WAN lines from approx. 40 globally distributed locations (Rebuilding the replicas is not an option).

    All servers are virtual, so we’re using virtual FC to share the library. This worked fine until about a month ago when we started getting timeout errors during tape operations. Using vFC with tapes is not a supported scenario (This was officially stated in the documentation as per October 2013).

    At this point we need to bring ourselves into a supported scenario – as well as solve the timeout issues.

    My main concern here is how to actually do this with a minimal risk to the data as well as minimum downtime. I also need to keep the retention lifecycle unharmed.

    As I see it: to keep retention I need to maintain the current Databases, this leaves me with two options:

    • Using a V2P tool and hope for the best.
    • Do recovery of the virtual DPM server to a new physical server.
      • Rebuild from scratch, attach iSCSI LUN’s and use DPMSync to restore the DBs and synchronize the replicas.
      • Do a BMR

    My concern is this: How do I make sure DPM will recognize the disks and in particular the replicas, if the disk are detached from the virtual DPM and reattached to the new physical DPM. If I use DPMSync will it by itself figure out which “new” disks contains which replicas and should this just work? Are there any additional precautions I should be aware of?

    Any advice on this is greatly appreciated. Thx.


    Wednesday, April 9, 2014 7:23 AM

Answers

  • Hi,

    <snip>
    My concern is this: How do I make sure DPM will recognize the disks and in particular the replicas, if the disk are detached from the virtual DPM and reattached to the new physical DPM. If I use DPMSync will it by itself figure out which “new” disks contains which replicas and should this just work?
    >snip<

    Taking the Virtual vs physical DPM server out of the equation because the same steps to rebuild a DPM server are the same.

    The disks in the DPM storage pool are dynamic, and Windows keeps track of volume guids in the LDM database on each dynamic disk.  This means Dynamic disks exposed to a new server and imported will retain the original volume guids which is what DPM uses to keep track of replica and recovery point volumes.   Assuming the Dynamic disk(s) are imported before running dpmsync -sync command, then DPM should recognize them and use them ok.

    PRECAUTION
    =========
    Make sure you have this Windows fix installed on the DPM servers before moving the iSCSI dynamic disks used in the DPM Storage pool to avoid loosing shadow copies.


    VSS software provider error when you use DPM to back up a Windows 8 or Windows Server 2012-based computer
    http://support.microsoft.com/kb/2914152

    2929881 0x80070005 error when you run DPM jobs in Windows Server 2012 R2
    http://support.microsoft.com/kb/2929881/EN-US


    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, April 9, 2014 10:06 PM
    Moderator