Degraded Virtual Disk

What Caused the Problem?

One or more physical disks have failed or have been removed in a disk group, resulting in this disk group becoming 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: 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 or removal in a RAID level 1, 5, 6, or 10 will cause a degraded virtual disk status. However, a degraded RAID 10 may have more than one failed physical disk if the failed physical disks belong to different mirrored pairs. A degraded RAID 6 may also have up to two failed physical disks.
When you replace a failed physical disk, data from the failed physical disk is rebuilt on the new physical disk. This rebuild should begin automatically after you insert the new physical disk.
Make sure the replacement physical disks are of the same type and 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.
The Service Action Allowed field in the Details area indicates whether you can safely remove the component. If the Service Action Allowed field is NO, then the affected component must remain in place until you service another component first.

Recovery Steps

If the physical disk was removed, there will not be an LED associated with a failure. Check the Recovery Guru details panel for any physical disk removal messages and replace any previously removed drives.

Locate all failed physical disks associated with this disk group (the status LED on the failed physical disks may be amber flashing). The Recovery Guru Details area also provides the location of the failed physical disks.

For each individual physical disk listed, check the Service Action Allowed status in the Details area.

If...

Then...

Service Action Allowed is YES

Go to step 4.

Service Action Allowed is NO

Answer the following question:

Are there other problems being reported in the Summary Area?

Yes - Fix these problems first and then return to this procedure after clicking the Recheck button.
No - Stop this procedure and contact your technical support representative.

If...	Then...
You want to replace the failed physical disk with a new physical disk	Remove the physical disk (its status LED may be amber flashing). Repeat steps 2 and 3 until you have removed all of the failed physical disks associated with this disk group, and then go to step 5.
You want to utilize an existing unassigned physical disk or the in-use hot spare to replace the failed disk in the disk group	Click on the Modify tab and then select Replace Physical Disks. Under Failed and Missing Physical Disks, select the physical disk that you would like to replace Under Available replacement physical disks, select the physical disk that you would like to use to replace the failed or missing physical disk Click on Replace Physical Disk. Result: If you choose an unassigned physical disk as a replacement, the affected virtual disks change to an Operation in Progress icon (in the Disk groups and virtual disks link) as the rebuild/copyback operations take place. When rebuild/copyback is completed, the virtual disks return to Optimal, and the hot spare physical disk returns to Standby. If you choose the Hot Spare as a replacement for the failed or missing physical disk, the Hot Spare role will be changed to Assigned. A new Hot Spare would need to be assigned if that functionality is desired Repeat above steps for each failed physical disk Click the Recheck button to rerun the Recovery Guru to ensure that the failure has been fixed.

Wait 30 seconds and then insert the new physical disks.

Notes:

Data rebuild should begin on the new physical disks. Their status LEDs and the activity indicator lights of the physical disks in the disk group will start flashing.
If you are replacing a physical disk in a storage array that contains hot spares, data rebuild will start on the hot spare before you insert the new physical disk. The data on the replacement physical disk may not be rebuilt until after it has completed the process on the hot spare.

If...	Then...
The data rebuild for all new physical disks does NOT automatically start within a few minutes	Go to step 6.
The data rebuild for all new physical disks in the disk group is complete	Go to step 7.

Perform the following steps on each replaced physical disk to start a manual rebuild on the physical disk:

Open a Command Prompt, and type the following command:

SMcli -n <storageArray_name>;

where storageArray_name is the name of the storage array listed in the Details area.

Note: If you receive an error from this command, change your working directory to the directory that contains the SMcli executable.

Execute the following command to manually rebuild a physical disk in a disk group:

start physicalDisk [enclosureID, slotID] reconstruct;

where enclosure_ID is the enclosure ID for the enclosure where the physical disk resides and slot_ID is the slot position within the enclosure.

Notes:

The commands above are case-sensitive, and must be entered exactly as shown.
When rebuild starts on a disk group, the icon changes to Operation in Progress in the Disk Groups and Virtual Disks dialog (accessed from the Summary tab by clicking the Disk groups & virtual disks link). When rebuild is completed, the disk group becomes Optimal .
Repeat this step for each physical disk that does not rebuild automatically in the disk group. When data rebuild for all physical disks in the disk group is complete, go to step 7.

Click the Recheck button to rerun the Recovery Guru. The failure should no longer appear in the Summary area.

Note: Additional information on this issue may be available. Please visit the Dell support website at support.dell.com and select your product model. Choose "troubleshooting" as your tool option, then search by this procedure title.