Migrating an existing disk array to a new RAID level

The SAS RAID controller supports migrating an existing RAID 0 or 10 disk array to RAID 10 or 0, respectively. This allows you to dynamically change the level of protection of a disk array while preserving its existing data.

When migrating RAID 0 to RAID 10, additional disks must be included into the RAID 10 disk array in order to provide the additional level of protection. The number of additional disks will be equal to the number of disks in the original RAID level 0 disk array. The capacity of the disk array will remain unchanged and the disk array remains accessible during the migration. The disk array is not protected by RAID 10 until the migration completes.

When migrating RAID 10 to RAID 0, no additional disks are included into the RAID 0 disk array. The number of disks in the resulting RAID 0 disk array will be reduced to half the number of disks in the original RAID 10 disk array. The capacity of the disk array will remain unchanged and the disk array remains accessible during the migration.

To migrate an existing array to a new level, do the following:

  1. Start the SAS Disk Array Manager by following the steps in Using the Disk Array Manager.
  2. Select Migrate an Existing SAS Disk Array to a New RAID Level.
  3. Select the SAS disk array which you want to migrate to a new level.
  4. Select the desired RAID level from the options shown.
  5. Select the desired stripe size from the options shown.
  6. Select additional disks to include if necessary to provide the desired level or protection. A screen will display similar to the following:
    +--------------------------------------------------------------------------------+

|                           IBM SAS Disk Array Manager                           |

|                                                                                |

|Move cursor to desired item and press Enter.                                    |

|                                                                                |

|  List SAS Disk Array Configuration                                             |

|  Create an Array Candidate pdisk and Format to RAID block size                 |

|  Create a SAS Disk Array                                                       |

|  Delete a SAS Disk Array                                                       |

|  Add Disks to an Existing SAS Disk Array                                       |

|  Migrate an Existing SAS Disk Array to a New RAID Level                        |

|  +--------------------------------------------------------------------------+  |

|  |             Include Disks during an SAS Disk Array Migration             |  |

|  |                                                                          |  |

|  | Move cursor to desired item and press F7. Use arrow keys to scroll.      |  |

|  |     ONE OR MORE items can be selected.                                   |  |

|  | Press Enter AFTER making all selections.                                 |  |

|  |                                                                          |  |

|  |   # hdisk6 requires 1 additional drives (maximum of 1) for RAID 10.      |  |

|  |                                                                          |  |

|  |   pdisk24   00044000  Active      Array Candidate        139.6GB         |  |

|  |                                                                          |  |

|  | F1=Help                 F2=Refresh              F3=Cancel                |  |

|  | F7=Select               F8=Image                F10=Exit                 |  |

|F1| Enter=Do                /=Find                  n=Find Next              |  |

|F9+--------------------------------------------------------------------------+  |

+--------------------------------------------------------------------------------+
  7. Press Enter to perform the RAID level migration.

    The migration progress percentage will be displayed next to the array being migrated.

    A screen will display similar to the following.

    Note: If the RAID disk array is in use, the RAID level description might not be updated until after the next IPL.
    +--------------------------------------------------------------------------------+

|                                 COMMAND STATUS                                 |

|                                                                                |

|Command: OK            stdout: yes           stderr: no                         |

|                                                                                |

|Before command completion, additional instructions might appear below.            |

|                                                                                |

|------------------------------------------------------------------------        |

|Name      Resource  State       Description              Size                   |

|------------------------------------------------------------------------        |

|sissas1   FFFFFFFF  Primary     PCI Express x8 Ext Dual-x4 3 Gb SAS RAID Adapter |

|tmscsi0   00FE0000  HA Linked   Remote adapter SN  081620E4                     |

|                                                                                |

|hdisk1    00FF0000  Optimal     RAID 6 Array           139.5GB                  |

| pdisk1   00040400  Active      Array Member            69.7GB                  |

| pdisk2   00040800  Active      Array Member            69.7GB                  |

| pdisk3   00040000  Active      Array Member            69.7GB                  |

| pdisk4   00040100  Active      Array Member            69.7GB                  |

|                                                                                |

|hdisk6    00FF0500  Rebuilding  RAID 10 Array          139.6GB Migrate 8%       |

| pdisk12  00040B00  Active      Array Member           139.6GB                  |

| pdisk24  00044000  Active      Array Member           139.6GB                  |

|                                                                                |

|                                                                                |

|                                                                                |

|F1=Help             F2=Refresh          F3=Cancel           F6=Command          |

|F8=Image            F9=Shell            F10=Exit            /=Find              |

|n=Find Next                                                                     |

+--------------------------------------------------------------------------------+
  8. After the RAID level migration is completed, run cfgmgr to update the description of the disk array.
Parent topic: Common controller and disk array management tasks


Last updated: Wed, May 24, 2017