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Not_Jake's avatar
Not_Jake
Level 4
8 years ago
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Why Basic Disk and not Dedupe Disk

Good Day Pros!

I know this is a stoop question. But I'd stuck with the reason why Instant Recovery Technology works on Basic Disk and not with Dedupe Disk and Disk Cartridge. Anyone can answer this in detail manner? And also can you give some Best Practices on using or performing of IRT? Thank you and have a Good Day!

  • OK so the way instant recovery works is that the Hypervisor attaches directly to the backup to disk location

    - for Hyper-V this uses CIFS

    - for Vmware this uses NFS

    Once attached to the backup to disk location the Hypervisor then directly mounts the required image files to start the virtual machine via the CIFS or NFS shares (which is why overall performance of an instantly recovered  VM may not be as good as the original VM)

    - for Hyper-V the mount is against VHD(x) files

    - for VMware the mount is against VMDK files

    What deduplication does however is a splits the backup sets into chunks and then the comparison between chunks across all your backups allows us to save overall storage space. These chunks are no longer presented as VHD(x) or VMDK files so the process from the Hypervisor to mount the image files cannot directly work.

    Note: we are researching the possibility go ways to address this limitation but cannot commit to anything currently

    With regards cartridge/detachable devices, I believe that testing showed issues with performance that was bad enough to cause problems (stability of VM that is handled by IRT/corruption of VM content etc.)

     

    As for best practices etc:

    There is information in  Appendix C (for VMware) and Appendix D (Hyper-V) of the Backup Exec 16 Administrators' Guide

    There are also sections in the Hyper-V and Vmware Best Practices docs available in this list

    https://www.veritas.com/content/support/en_US/doc-viewer.72686287-129480082-0.index.html

    In the above list it may also worth being familiar with the content of the general "Granular Recovery Technology" best practices document as well

     

  • OK so the way instant recovery works is that the Hypervisor attaches directly to the backup to disk location

    - for Hyper-V this uses CIFS

    - for Vmware this uses NFS

    Once attached to the backup to disk location the Hypervisor then directly mounts the required image files to start the virtual machine via the CIFS or NFS shares (which is why overall performance of an instantly recovered  VM may not be as good as the original VM)

    - for Hyper-V the mount is against VHD(x) files

    - for VMware the mount is against VMDK files

    What deduplication does however is a splits the backup sets into chunks and then the comparison between chunks across all your backups allows us to save overall storage space. These chunks are no longer presented as VHD(x) or VMDK files so the process from the Hypervisor to mount the image files cannot directly work.

    Note: we are researching the possibility go ways to address this limitation but cannot commit to anything currently

    With regards cartridge/detachable devices, I believe that testing showed issues with performance that was bad enough to cause problems (stability of VM that is handled by IRT/corruption of VM content etc.)

     

    As for best practices etc:

    There is information in  Appendix C (for VMware) and Appendix D (Hyper-V) of the Backup Exec 16 Administrators' Guide

    There are also sections in the Hyper-V and Vmware Best Practices docs available in this list

    https://www.veritas.com/content/support/en_US/doc-viewer.72686287-129480082-0.index.html

    In the above list it may also worth being familiar with the content of the general "Granular Recovery Technology" best practices document as well