Degraded Virtual Disk

What Caused the Problem?

One or more physical disks have failed in a disk group and the virtual disks associated with this disk group have become degraded . The data on the virtual disks is still accessible. However, data may be lost if another physical disk in the same disk group fails. The Recovery Guru Details area provides specific information you will need as you follow the recovery steps.

Caution: Possible loss of data accessibility. Do not remove a component when either (1) the Service action (removal) allowed (SAA) field in the Details area of this recovery procedure is NO (), or (2) the SAA LED on the affected component is OFF (note that some products do not have SAA LEDs). Removing a component while its SAA LED is OFF may result in temporary loss of access to your data. Refer to the following Important Notes for more detail.

Caution: Electrostatic discharge can damage sensitive components. Always use proper antistatic protection when handling components. Touching components without using a proper ground may damage the equipment.

Important Notes

Usually, a single physical disk failure in a RAID 1/10, 3, or 5 disk group or up to two physical disk failures in a RAID 6 disk group will cause a degraded virtual disk status. However, a degraded RAID 1/10 disk group may have more than one failed physical disk if the failed physical disks belong to different mirrored pairs.
When you replace a failed physical disk, data from the failed physical disk is reconstructed on the new unassigned physical disk. This reconstruction should begin automatically after you insert the new physical disk.
Make sure the replacement physical disks have a capacity equal to or greater than the failed physical disks you will remove.
You can replace failed physical disks while the affected virtual disks are receiving I/O only if there are no other operations-in-progress for those virtual disks.
Service Action Allowed Important Information:
- The Service action (removal) allowed field in the Details area indicates whether or not you can safely remove the component. If the SAA field is NO (), then the affected component must remain in place until you service another component first.
- The Service action LED on Component field in the Details area indicates whether or not a physical SAA LED is present on the hardware component. This field does NOT indicate whether the LED is ON or OFF (that indication is provided by the Service action (removal) allowed field).
- If a component does not have an SAA LED, then it is OK to remove the component when its fault LED is lit and the Service action (removal) allowed field = YES () in the Details area.
- The Service action (removal) allowed field shown in the Details area and the physical SAA LED on the hardware component (if supported) MUST match before you remove the affected component. In rare cases (such as multiple problems), the status of the LED and the SAA field may not match. If there is a mismatch, then you should NOT remove the component until these indications match. The Recovery Steps will help you to make this determination.

Recovery Steps

1	Check the Details area to identify the failed physical disk(s).
2	Remove all failed physical disks associated with this disk group (the fault indicator lights on the failed physical disks should be on). To make a visual association of the failed physical disks, select one of the degraded virtual disks in the Logical View of the Array Management Window, which is listed in the Recovery Guru Details area. Each failed physical disk associated with the disk group will have an association dot underneath it.
3	Wait 30 seconds, then insert the new physical disk(s). The fault indicator light on the new physical disk(s) may become lit for a short time (one minute or less). Result: Data reconstruction should begin on the new physical disk(s). Their fault indicator lights will go off and the activity indicator lights of the physical disks in the disk group will start flashing. When the reconstruction starts, the disk group's virtual disk icons in the Logical View of the Array Management Window change to Operation in Progress , then to Optimal , as the virtual disks are reconstructed. Notes: If you are replacing a physical disk in a storage array that contains hot spares, physical disk reconstruction will start on the hot spare before you insert the new physical disk. The data on the replacement physical disk may not be reconstructed until after it has completed the process on the hot spare. If reconstruction does not start within a few minutes, select the new physical disk; then, select Advanced >> Recovery >> Reconstruct Physical Disk to start reconstruction on the physical disk. To monitor reconstruction progress on the affected virtual disks or to change the reconstruction rate, select the reconstructing virtual disk; then, select Virtual Disk >> Properties. Note that once the operation in progress has completed, the progress bar is no longer displayed in the properties dialog. Replace only one physical disk at a time for each disk group. Each physical disk should complete reconstruction before the next physical disk begins reconstruction. Wait until the reconstruction is completed for all virtual disks before continuing.
4	Click Recheck to rerun the Recovery Guru. Once ALL failed physical disks are replaced, then this failure should no longer appear in the Summary area. If the failure appears again after all failed physical disks have been replaced, contact your technical support representative.