Reusing FlashCopy Logical Drives: Additional Information for HP-UX – LVM Logical Volumes

Typically, after a has been created, it would be disabled until a new point-in-time image of the same is required. Use this procedure to create a new point-in-time image of the same base logical drive.

  1. Stop all activity to the base logical drive at this point (or data transfer suspended). This action makes sure that an accurate point-in-time image of the base logical drive is captured.
  2. Unmount the base logical drive.
  3. In the storage management software, re-create the flashcopy logical drive by using one of these methods:

    recreateSnapshot volume
    

    For command reference information about re-creating a flashcopy logical drive, refer to the online help topics in the Enterprise Management Window.

  4. Remount the base logical drive (to its original ).
  5. If I/O activity to the base logical drive was stopped or data transfer was suspended, resume I/O activity to the base logical drive at this time (or re-enable data transfer).
  6. Complete these steps to import the flashcopy logical drives into the Logical Volume Manager.
    1. Create a new directory for the new ; for example:

      mkdir /dev/vg02
      

    2. Create a group node for the new array; for example:

      mknod /dev/vg02/group c 64 -0x020000
      

    3. Import the flashcopy logical drive . At the host prompt, type this command and press Enter:

      vgimport /dev/vg02 snapshot-block-node-1 snapshot-block-node-2
      

      For example:

      vgimport /dev/vg02 /dev/dsk/c66t0d1 /dev/dsk/c69t0d1
      

    4. Make sure that the /dev/dsk device files will be the flashcopy logical drive and that they exist using the utility or the HP-UX ioscan utility.

      A warning appears that indicates that a backup of the array being imported might not exist on the host. This message is only a warning and can be ignored. The import continues and completes successfully.

      The backup for this array is created when it is later exported.

    5. Activate the new array; for example:

      vgchange -a y /dev/vg02
      

  7. If a file system existed on the base logical drive, it also exists on the flashcopy logical drive. However, before the flashcopy logical drive can be mounted, run a file system check to make sure that the file system is consistent; for example:

    fsck /dev/vg02/lvol01
    

  8. Mount the flashcopy logical drive to its intended host.
  9. Use theflashcopy logical drivewith your backup application (or other application).
  10. Unmount the flashcopy logical drive.
  11. After the flashcopy logical driveis no longer required, disable the flashcopy logical drive.

    If you disable the flashcopy logical drive instead of deleting it, you can retain the flashcopy logical drive and its associated . Then, when you need to create a different flashcopy of the same base logical drive, you can re-create the disabled flashcopy logical drive. This action takes less time than creating a new flashcopy logical drive and stops any reduction in performance that might occur if the flashcopy logical drive remains available.

    For more information, refer to the Disabling a FlashCopy Logical Drive online help topic and the Re-creating a FlashCopy Logical Drive online help topic.

    For command reference information about disabling and re-creating a flashcopy logical drive, refer to the online help topics in the Enterprise Management Window.

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