Dell Raid Hard Drive Failure

competitionscafe

My Dell PC (Dimension 8400) is only about 14 months old but now displays the message "A RAID volume is degraded bacause of failed hard drives". The PC has 2 RAID mirror hard drives (I think this means that everything is backed up onto both drives in case one fails which it seems to have done).

Question is what do I do next? Do I need to replace with a new hard drive or is it fixable?

Thanks.

intel

competitionscafe wrote:

My Dell PC (Dimension 8400) is only about 14 months old but now displays the message "A RAID volume is degraded bacause of failed hard drives". The PC has 2 RAID mirror hard drives (I think this means that everything is backed up onto both drives in case one fails which it seems to have done).

Question is what do I do next? Do I need to replace with a new hard drive or is it fixable?

Thanks.

Well a new HDD is the best option but I would check the drive itself
find out the specs of the PC how many Drives and make and model of drive then go to Drive manufacturers site and download non-destructive testing tools.

And dont forget http://www.ultimatebootcd.com/ it is a little more advanced though.

CIS

For two disk your right in saying that the disk are 'mirrored' and your data should be safe. The other option would be a striped disk where the information is split across 2 (or more) disks, if this had been the case you would have lost everything.

If the disk is knackered, it may still be under warranty by the hard drive manufacturer even if its out of dell's warranty.

John_Gray

Before you do anything expensive, power off and open the case up and check that the connectors at each end of each thin blue (?) cable are tightly seated.

The message(s) you get should give you a clue which of the two, if not both, drives are failing. If this is not clear, your best bet might be to find "someone" with a computer and a SATA disk controller who would be prepared to try each disk in turn to see which if either, or both, drives are unwell. "Degraded" should mean that one drive is working and the other isn't. You could try powering off, then removing the power connector from each drive in turn to hear if it "spins up" when the power is switched on again.

The problem with mirrored RAID-1 is that if bad data is written to one drive, this is faithfully copied to the other drive.

I presume you didn't get an extended maintenance contract with Dell? My 2 x 120 GB drives "failed" (I reckon the boot block just got erased) some time back, and they were replaced free-of-charge by 2 x 400 GB drives.

John

charlieheard

CIS wrote:

For two disk your right in saying that the disk are 'mirrored' and your data should be safe. The other option would be a striped disk where the information is split across 2 (or more) disks, if this had been the case you would have lost everything.

If the disk is knackered, it may still be under warranty by the hard drive manufacturer even if its out of dell's warranty.

CIS is right that RAID can spread data across disks (or stripe it). The whole point of RAID (Redundant Array of Inexpensive Disks) was that it was cheaper to have several cheap disks with the data duplicated in case of failure. So a single disk failure should mean you've NOT lost any data - that's why it was designed. RAID arrays can have various combinations of disks (up to 5), which allow for greater redundancy. Your 2 disks will almost certainly be mirrored, so that exactly the same information is written to both disks.

First read the manual - that should tell you what you need to do check what is wrong before you replace the disk. It may be that the RAID hardware has detected that the disks are out of sync and just need some form of disk checking. The manual will also tell you how to replace one of the disks if something's gone badly wrong. (RAID 5 would allow you to pull out and replace disks without worrying).

I'm assuming you want to keep the 2 disks as RAID for protection of your data. IMHO RAID seems a bit OTT unless your data is of vital importance, so you could just make the disks non-RAID, and use some backup software to store important information on a DVD or CD instead.