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Creating a disk array

A disk array is created using a set of Active Array Candidate pdisks.

For disk arrays with data redundancy (RAID 5, 6, and 10), if all of the pdisks are in the Zeroed state, the array will become immediately protected against failures. However, if one or more of the pdisks are not Zeroed, the newly created array will initially be in the Rebuilding state. It will be unprotected against disk failures until parity data on all of the disks has been recalculated. Ensure that all pdisks are placed in a Zeroed state by selecting Create an Array Candidate pdisk and format to 528 Byte Sectors before creating a disk array to fully initialize the pdisks and provide the shortest time to create the disk array.

A disk array must be created with either all HDDs or SSDs. Disk arrays consisting of HDDs and disk arrays consisting of SSDs may coexist on the same controller.

To create a IBM® SAS Disk Array, do the following:

  1. Start the IBM SAS Disk Array Manager by following the steps in Using the Disk Array Manager.
  2. Select Create a IBM SAS Disk Array.
  3. Select the appropriate IBM SAS RAID Controller on which you want to create an array.
  4. Select the RAID level for the array. For more information about selecting an appropriate RAID level, see Supported RAID levels.
  5. Select the stripe size in kilobytes for the array. For more information about the stripe-size parameter, see Stripe-unit size.

    A selection screen similar to the following representation displays. It will display a list of Array Candidate pdisks and notes regarding array requirements. The minimum and maximum number of supported disks will be specified, along with any other specific requirements for the array. Select the disks that you want to use in the array according to the requirements on this screen.

    +--------------------------------------------------------------------------+
    |                     Select Disks to Use in the Array                     |
    |                                                                          |
    | 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.                                 |
    |                                                                          |
    |   # RAID 5 supports a minimum of 3 and a maximum of 18 drives.           |
    |                                                                          |
    |                                                                          |
    |   pdisk1    00040200  Active      Array Candidate         34.8GB Zeroed  |
    |   pdisk3    00040900  Active      Array Candidate         34.8GB Zeroed  |
    |   pdisk4    00040000  Active      Array Candidate         34.8GB Zeroed  |
    |   pdisk5    00040300  Active      Array Candidate         34.8GB Zeroed  |
    |                                                                          |
    | F1=Help                 F2=Refresh              F3=Cancel                |
    | F7=Select               F8=Image                F10=Exit                 |
    | Enter=Do                /=Find                  n=Find Next              |
    +--------------------------------------------------------------------------+

    A SMIT Dialog Screen summarizes your selections.

  6. Press Enter to create the array.

You can now add the disk array to a volume group. Logical volumes and file systems can also be created. Use standard AIX® procedures to perform these tasks, and treat the array in the same way that you would treat any hdisk.



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Last updated: Thu, October 10, 2013