On a Dell SAS 5/ir RAID controller, I have a RAID 1 array which is Degraded.
One drive has failed.
Upon replacing this drive the controller doesn't automatically resync the array.
There's an option to manually add the new drive to the array, but when I try this, the controller bios shows:
Screenshots: http://imagebin.ca/view/QdCuJI5.html
WARNING! Data on physical disks that are part of the virtual disk will be LOST!
Are you sure you want to commit RAID Configuration changes?
Now – it is obvious that the drive I put in to replace the failed one will have data loss, as it should get data from the working drive synced onto it.
However, the Controller's message doesn't state what drive there'll be data loss. It could be that making this change will create a fresh RAID LUN with no data. I don't know, and the controller doesn't make it clear.
Can anyone say for definite that this will not affect the data on the original drive?
It just worries me that the message states "physical disks" – plural, and not "Data on the secondary physical disk that you just added will be LOST!"
No doubt this is what the message means, but I don't like guessing with critical data!
Many thanks!
Best Answer
Having come across the same issue on an identical platform again, with no valuable data, I decided to see what would happen and just pressed "Commit Changes" after being given that warning.
It turned out that this does did not lose the array, and added the new disk to the existing raid 1 array, as expected.
As I suspected, the error message was just too vague: it should have stated that "You will lose data on the new member disk that you are about to add to the existing array, the existing drive will not be touched'.
Potentially they made the error message intentionally vague so they could re-use it.