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DPM2012 R2 and Virtual Tape Library ( VTL ) - How to allocate disk volume? RRS feed

  • Question

  • Hello,

    We plan to upgrade our backup solution running DPM2010 to DPM2012 R2 with a new storage pool

    While we had until now a direct attached storage (SAS connection) to the DPM server, our vendor proposes a storage model with VTL (Virtual Tape Library) interface.

    If I do understand, VTL acts like a Virtual Tape Library and thereforce appears like a "physical tape Library" under DPM Library management, right? Instead of having physical tape, you manage virtual tape.

    In that case, once you attache your storage to your DPM server, it only appears as a tape libray, and you can't allocate it for a disk pool allocation?

    In that case, if you plan to have short-term protection with Disk2Disk backup, it's not possible Under DPM, is it?

    Does anyone have a experience return of using SAN storage with VTL interface?

    Regards,

    Evan

    Wednesday, March 18, 2015 1:13 PM

Answers

  • Hi,

    That is correct, if the storage device is configured as a Virtual Tape Library (VTL) - then Windows will see that device as a tape library and not as block level storage that DPM Storage pool requires.   You will only be able to use it as a tape library in DPM for short term or long term Disk-2-Tape backups.


    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, March 18, 2015 4:04 PM
    Moderator

All replies

  • Hi,

    That is correct, if the storage device is configured as a Virtual Tape Library (VTL) - then Windows will see that device as a tape library and not as block level storage that DPM Storage pool requires.   You will only be able to use it as a tape library in DPM for short term or long term Disk-2-Tape backups.


    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, March 18, 2015 4:04 PM
    Moderator
  • Mike is correct, DPM cannot use a VTL as a "primary backup device" ......by primary I mean the location where DPM keeps its "replicas"...that is usually only for short term storage. It can use VTL as a second tier of storage (long term). IMHO, this is not ideal..... in today's day and age.

    Here is another thing to consider....

    In the past I have worked with Overland virtual tape libraries which had the capability of functioning as an iSCSI target as well. That allowed the disk space available on the Overland VTL to be mounted to a backup server (like DPM) as a local disk. You may want to look at VTLs which have that option.

    That way, DPM will be able to utilize your disk based backup appliance a.k.a VTL for its primary backup storage....and essentially utilize the advantages of hardware based de-duplication.....the holy grail of backups ;-)

    We went with HP StoreOnce devices which do NOT have that option.


    -Rajeev rajdude.com

    Tuesday, March 24, 2015 5:49 PM
  • It might help you to connect with the person who wrote the review whose link I included below--The reviewer said he used SAN as well as the HP StoreOnce that Rajeev mentioned he used in his response. My company, IT Central Station, provides reviews of products like VTL interfaces and might help give you some more information, particularly as you can talk to the specific reviewers if you would like by clicking on their profiles.

    http://www.itcentralstation.com/product_reviews/storeonce-review-by-juergen-petersen?tid=thread-pr01-cm006-t013-l01



    • Edited by Sarah Sukin Tuesday, June 23, 2015 7:23 AM extra enters put into comment
    Tuesday, June 23, 2015 7:21 AM