Replacing a disk in a SAS RAID adapter

The data from the failing disk can be reconstructed to a replacement hot-spare disk if the hot-spare disk is available during the failure. If the hot-spare is active and is available during the failure, the state of the affected disk array is either Rebuilding or Optimal because of the use of a hot-spare disk.

1. If you want the new disk to be designated as a hot-spare disk, you must first prepare the disk to be used in the array. Complete the following steps to prepare the disk to be used in a disk array. Otherwise, go to step 2.
   Note: Hot-spare disks are useful only if their capacity is greater than or equal to that of the smallest capacity disk in a disk array that is in Degraded state.
   1. Start the IBM® SAS Disk Array Manager by completing the following steps:
      1. Start AIX® diagnostics and select Task Selection on the Function Selection display.
      2. Select RAID Array Manager > IBM SAS Disk Array Manager.
   2. Select Create an Array Candidate pdisk and Format to 528 Byte Sectors.
   3. Select the appropriate IBM SAS RAID Controller.
   4. Select the disks from the list that you want to prepare to be used in the disk arrays.
   5. Return to the IBM SAS Disk Array Manager
   6. Select RAID Array Manager > IBM SAS Disk Array Manager.
   7. Select Change/Show SAS pdisk Status > Create a Hot Spare > IBM SAS RAID Controller.
   8. Select the pdisk that you want to designate as a hot-spare disk.
   9. Return to the system service procedure that sent you here.
2. If the state of the array is Failed or Missing go to step 3. If the state of the array is Degraded, complete the following steps to change the state of the array to Optimal:
   1. Start the IBM SAS Disk Array Manager by completing the following steps:
      1. Start AIX Diagnostics and select Task Selection on the Function Selection display.
      2. Select RAID Array Manager > IBM SAS Disk Array Manager > Reconstruct a SAS Disk Array.
   2. Select the pdisk that you want to reconstruct.
   3. Return to the system service procedure that sent you here.
3. If the state of the array is Failed or Missing, delete and recreate the array, and then restore the data from the backup disk by completing the following steps:
   Attention: All data on the disk array will be lost.
   1. Start the IBM SAS Disk Array Manager.
      1. Start AIX diagnostics and select Task Selection on the Function Selection display.
      2. Select RAID Array Manager > IBM SAS Disk Array Manager.
   2. Select Delete a SAS Disk Array > IBM SAS RAID Controller.
   3. Select the disk array to delete.
   4. Select Create an IBM SAS Disk Array.
   5. Select the IBM SAS RAID Controller on which you want to create an array.
   6. Select the RAID level for the array. For more information about selecting an appropriate RAID level, see Supported RAID levels.
   7. Select the stripe size in kilobytes for the array. For more information about the stripe-size parameter, see Stripe-unit size.
   8. Select the disks that you want to use in the array according to the requirements displayed on the screen.
   9. Press Enter to create the array.

      Data must be restored from a backup disk. The disk array can be added to a volume group. Logical volumes and file systems can also be created. Use the standard AIX procedures to complete these tasks, and use the array in the same way that you would use any hdisk.

   10. Return to the system service procedure that sent you here.