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QTS 5.0.x

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Expanding a Storage Pool by Adding Disks to a RAID Group

The total storage capacity of a storage pool can be expanded by adding one or more additional disks to a RAID group. This operation can be performed while the pool is online and accessible to users.

  • Adding disks to a RAID 1 group changes the RAID type of the group to RAID 5.

  • To expand a RAID 50 or RAID 60 group, every sub-group must be expanded with the same number of disks.

  1. Verify the following:
    • The storage pool you want to expand contains at least one RAID group of type: RAID 1, RAID 5, RAID 6, RAID 50 or RAID 60.

    • The NAS contains one or more free disks. Each free disk must be the same type as the other disks in the RAID group (either HDD or SSD), and have a capacity that is equal to or greater than the smallest disk in the group.

    • The status of the RAID group that you want to expand is Ready.

  2. Go to Storage & Snapshots > Storage > Storage/Snapshots.
  3. Select a storage pool.
  4. Click Manage.

    The Storage Pool Management window opens.

  5. Select Action > Expand Pool.

    The Expanding Storage Pool Wizard window opens.

  6. Select Add new disk(s) to an existing RAID group.
  7. Select a RAID group.

    The group must be of type: RAID 1, RAID 5, RAID 6, RAID 50, RAID 60.

  8. Click Next.
  9. Select one or more disks.

    If you select RAID 5, 6, 50, or 60 for the RAID type, you cannot select more than 16 disks.


    All data on the selected disks will be deleted.

  10. Click Next.
  11. Optional: Configure SSD over-provisioning.

    Over-provisioning reserves a percentage of SSD storage space on each disk in the RAID group to improve write performance and extend the disk's lifespan. You can decrease the amount of space reserved for over-provisioning after QTS has created the RAID group.


    To determine the optimal amount of over-provisioning for your SSDs, download and run SSD Profiling Tool from App Center.

  12. Click Next.
  13. Click Expand.

    A confirmation message appears.

  14. Click OK.
  15. Optional: For a RAID 50 or RAID 60 pool, repeat these steps for each sub-group.

QTS starts rebuilding the RAID group. The storage capacity of the pool increases after RAID rebuilding is finished.