RAID 1/0 failed but drive seems to work fine??

JohnnySky

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Mar 31, 2006
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Using Intel Matrix late last night I got an error that one of my drives failed. I quickly replaced the drive and the array rebuilt fine. Before RMAing the drive I figured i'd give it a test and hook it up to another PC. I was unable to access the drive at all or even format it but I decided to give it a try as a boot drive and install an OS on it forcing it to format. The drive now seems to be operating normally... I'm so confused why this would happen. Is it typical that a drive fails but isnt dead? Is it safe for me to re-insert the drive back into the array?
 

jrst

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May 8, 2009
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This isn't too unusual. Consumer drives are generally engineered to hide a lot of error recovery activity. E.g., drive tries to read sector. Read fails. Drive retries. Read fails. Repeat N times. Retries can involve different activities (moving the heads around, calibrating, remapping, etc.). All that takes time. If it takes too long, the controller decides the drive has failed and drops it out of the array. Try again a bit later and it may work just fine (and may be fine). "RAID ready" drives expose more of the error/recovery process so the controller can see what's happening.
 

dgrolem

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May 17, 2009
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Just had this happen with a Seagate drive. Mine was a bit different, in that I could "successfully" re-build by right-clicking the drive in Matrix and select "Set as Normal". Happened 3 times in 4 days.

I called Seagate and they said to exchange the drive.