Intel RAID 5 fails with single disk failure

[foop]

I have a 3-disk RAID 5 array using the onboard Intel RAID controller on my mobo. Or rather, I used to have one. One of the disks failed this morning. The Intel Rapid Storage Technology interface in the BIOS boot process is reporting the RAID as failed. The Intel software once the machine has booted (it's not the boot volume) is reporting the RAID as failed. None of the usual options you'd expect for a degraded RAID are there.

The other disks in the array are reporting as having normal status and being members of the array.

It's a MSI Z97 MPower mobo with 3TB WD Green SATA HDs.

Has anyone else had any experience with this? There are a few posts on the Intel forums from people with similar problems but no solutions.

Short of visiting Intel and beating them repeatedly round the head with the faulty disk whilst shouting "RAID 5 should cope with a single disk failure" over and over again, I'm at a loss as to what to do.

 

[Quartz]

From Intel's KB:

Follow these steps to rebuild a RAID volume after replacing a failed hard drive from a redundant RAID volume (RAID 1,5,10):

Turn on the system.
Click Start.
Click All Programs.
Click Intel.
Click Intel® Rapid Storage Technology.
Click Rebuild to another disk.
Select the replacement hard drive and click Rebuild.

You have to put in the new HDD first. You might find it quicker to reset the array and restore from your backup.

 

[foop]

From Intel's KB:

That's the instructions for a degraded array, not a failed array.

You have to put in the new HDD first. You might find it quicker to reset the array and restore from your backup.

So you're saying that the array will report as failed rather than degraded until you have a suitable spare disk available? That's rather counter-intuitive (and completely unlike any other RAID controller I've ever worked with, but I'm not discounting Intel's ability to be completely unlike everyone else).

I haven't got a replacement disk yet, but I'll give it a go.

 

[foop]

Well, the problem seems to have resolved itself.

I suspect there's something in some sort of volatile storage that was breaking things.

On the day it failed, I rebooted the machine many times with the failed disk present and removed but it always reported the array as failed. It shouldn't do this with a single disk failure in a RAID 5 array. After I gave up and left the machine off for a day, on the next boot it reported the array as degraded, as it should have done in the first place.

I got a replacement disk and it's currently rebuilding the array.

 

[levontraut]

Well, the problem seems to have resolved itself.

I suspect there's something in some sort of volatile storage that was breaking things.

On the day it failed, I rebooted the machine many times with the failed disk present and removed but it always reported the array as failed. It shouldn't do this with a single disk failure in a RAID 5 array. After I gave up and left the machine off for a day, on the next boot it reported the array as degraded, as it should have done in the first place.

I got a replacement disk and it's currently rebuilding the array.

Just on a side note, i would not user green drives in any raid array.
If you are I would also play around with the power settings that the drives do not go too sleep.