Creating a RAID Bitmap

If a disk is temporarily disconnected from its RAID group and then reconnected, the RAID group must resynchronize all of its data. This process may take a long time. If the RAID group has a bitmap, only changes that were made after the disk was removed need to be synchronized, greatly speeding up the process.

A disk can become temporarily disconnected in the following situations.

  • You can only create bitmaps for RAID 1, RAID 5, RAID 6, and RAID 10 groups.

  • Enabling a RAID bitmap causes the RAID groups performance to decrease slightly.

  • A bitmap improves resynchronization time only if the same disk is added back to the RAID group. If a new disk is added to a RAID group, the bitmap makes no difference.

  1. Go to Main Menu > Storage & Snapshots > Storage/Snapshot.
  2. Select a storage pool or single static volume.
  3. Click Manage.
  4. Select a RAID 1, RAID 5, RAID 6, or RAID 10 group.
  5. Click Manage and then select Enable Bitmap.

    A confirmation message appears.

QTS creates a bitmap for the RAID group.