raid 0 problems

[Technomage]

On Sunday 26 March 2006 21:45, Alan Dayley wrote:
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> Technomage wrote:
> > since I *know* this can be done, there has to be a way for someone in my
> > position to be able to do this without expending THOUSANDS of DOLLARS (in
> > money I don't even have) to do this.
>
> One trick I have been successful doing is to find a working hard drive
> of the same model.  Then, assuming the platters and motors are good, you
> can replace the logic board on one drive with the logic board on the
> good drive.  Do this very carefully or you will end up with two dead
> drives!  But, if the logic board "contains" the problem, this can get
> the drive up and running again.  The description of the actual drive
> failure seems to point to a logic board problem so this may work for you.

I concur. We are, however, without a proper sized torx bit to accomplish this 
(will wait and head off to the hardware store tomorrow to find one)

>
> RAID 0 with two drives means half the data is on one and half on the
> other.  The RAID logic will put, for example, 4 blocks on one and then 4
> blocks on the other and so on.  That means every 4th (or whatever number
> it was using) block is on the dead drive.  That is hard to recover from
> because the data doesn't make sense with only one of the drives.  There
> are other issues and possible complications but you probably are
> studying up on all of that.

the above is true in HARDWARE RAD-0. However, given that this was a linux 
(suse 10+) software raid-0, it appears (and was proven by direct observation) 
that the data was written in serial fashion from 1 drive and spanning to the 
second. 

>
> This is why it costs so much to recover.  It's not easy and take
> experience to do efficiently.  I hope you can get the dead drive up
> since that would be the easiest way to recover.

understandable.

we are exploring all available options though (and I have contacted the 
developer though have not yet received a reply).


>
> Good Luck!

thank you!