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I've got an install of Windows Server 2008 Enterprise. It's running software RAID-5 with five disks. The disks were originally formatted under Windows Server 2003, but came up fine once I installed Windows Server 2008.

The issue I'm having is that every time I reboot the server, the RAID comes up with a "Failed Redundancy" - the data stays available.

I have 4 disks on a PCI SATA controller, and one of the disks connected to the motherboard's on-board SATA ports. (The other on-board port has the system disk connected.)

I was having Disk #4 fail consistently, so I tried swapping the cables on the controller end. I swapped the on-board RAID disk with one on the PCI controller. Same issue now, expect with disk #1.

Once the system's up, I can reactivate the RAID, it will resync for a while, then go to "Healthy", and will stay that way for an indefinite amount of time - until I reboot. As soon as I reboot, the disk drops again.

I've ruled out disk + cable with the recabling. I don't believe it would be the controller as it seems to work fine most of the time - only failing on reboot, and the other port on the same controller connects the system disk - which is clearly working.

I did look in the event log, but didn't see anything particularly relevant (although I didn't know what I was looking for - just looked for anything with a "Warning" or "Error" symbol that looked disk-related :)).

I'm not particularly familiar with RAID on Windows, does anyone have any idea why this might be doing this? Any idea how to fix it?

Any suggestions appreciated!

-- Adam

share|improve this question
Please tell us what hardware you are using. You didn't even tell us the brand of RAID controller. Or maybe you are using software RAID. IMHO, RAID 5 is garbage. Don't use it. Do RAID 10 or similar. – d-_-b Jun 3 '10 at 0:38
I actually specified in the first sentence that it's software RAID-5. And thanks, but I'm aware of the benefits/drawbacks of the various RAID levels and am quite content with RAID-5. – Adam Jun 3 '10 at 23:47

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