Replacing a Failed Hard Drive in an AIX RAID 5 Array
IBM Small Systems Hard Drive Replacement Process: RAID5
I. Symptom Description
One IBM Small System with a RAID controller, containing 3 internal hard drives configured in RAID5 with no hot spare.
The second hard drive is showing a yellow fault indicator light.
II. Perform rootvg backup (mksysb) and data backup (strongly recommended)
After backing up the data, for safety, stop application access to the hard drives.
III. Fault Confirmation
Execute lsdev –Cc pdisk/hdisk and errpt commands to check if the system reports any hard drive errors.
Navigate to diag -> Task selection -> RAID Array Manager ->
IBM SAS Disk Array Manager -> List IBM SAS Disk Array configuration to check RAID information and pdisk status.
hdisk0 0B-08-ff-0,0 Degraded RAID 5 Array 484.2GB
pdisk0 0B-08-00-5,0 Failed Array Member 242.8GB
pdisk1 0B-08-01-5,0 Active Array Member 242.8GB
pdisk2 0B-08-00-3,0 Active Array Member 242.8GB
Confirm the hard drive slot information using the following steps:
Diag->Task Selection->RAID Array Manager->IBM SASDisk Array Manager-> Diagnostics and Recovery Options->SCSI and SCSI RAID Hot Plug Manager-> Identify a Device Attached to a SCSI Hot Swap Enclosure Device
Select the corresponding hard drive and press F7 to confirm the slot location (the yellow light on the disk is flashing).
IV. Perform Hard Drive Replacement
1) Replace the hard drive using hot plug as follows:
diag?
Task Selection?
RAID Array Manager?
IBM SASDisk Array Manager?
Diagnostics and Recovery Options?
SCSI and SCSI RAID Hot Plug Manager?
Replace/Remove a Device Attached to an SCSI Hot Swap Enclosure Device
Replace the faulty hard drive and press Enter.
Then press F3 to return to the previous menu level.
SCSI and SCSI RAID Hot Plug Manager
Configure Added/Replaced Devices
2) After replacing the hard drive, return to
diag-> Task selection ->
RAID Array Manager ->
IBM SASDisk Array Manager ->
List IBM SAS Disk Array configuration
You can see that the pdiskX status is failed, as shown in the figure below:
3) hdisk0 0B-08-ff-0,0 Degraded RAID 5 Array 484.2GB
pdisk0 0B-08-00-5,0 Failed Array Member 242.8GB
pdisk1 0B-08-01-5,0 Active Array Member 242.8GB
pdisk2 0B-08-00-3,0 Active Array Member 242.8GB
7) Execute lsdev –Cc pdisk to verify that pdisk0 is available.
V. Rebuild the RAID
diag-> Task selection ->
RAID Array Manager ->
IBM SASDisk Array Manager ->
Reconstruct a IBM SASDisk Array
Select the newly created disk. pdisk0 Initiate rebuild (approximately 4 hours required for a 146GB HDD).
Rebuild progress will be displayed; you may exit the rebuild process to allow it to run in the background.
VI. After rebuild completion, confirm the RAID status is optimal.
diag-> Task selection ->
RAID Array Manager ->
IBM SASDisk Array Manager ->
List IBM SASDisk Array configuration