On Wed, 26 Aug 2009 18:10:38 +0200
cpghost <cpgh...@cordula.ws> wrote:

> On Mon, Aug 24, 2009 at 02:51:41PM -0600, Tim Judd wrote:
> > >> Buy spinrite, no matter what.
> > 
> > It's OS/FS independent.  it works on the bits stored on the magnetic
> > platters, NOT on a filesystem.  TiVo, Linux, BSD and Mac OSX drives
> > are treated the same.  Bits on a magnetic platter.  It's recovery
> > stems from the randomization and movement of the head to the sector
> > in question that allows it to salvage any bits it can (for example,
> > other recovery will abandon 512bytes if 1 bit cannot be read.
> > spinrite will recover 512bytes-1bit to a hard drive's spare sector
> > once spinrite says "i'm done working with this sector".)  It leads
> > to a very successful rate.
> (Disclaimer: I'm not familiar with spinrite.)
> 512bytes-1bit may be read back, but you can't be sure that those are
> the correct bytes! IIRC, sectors are usually protected by some kind of
> ECC. Simply ignoring the ECC and reading raw magnetic data will all
> too often result in corrupt sectors.
> Of course, if you have out-of-band error correction or at least error
> detection mechanisms (like .PAR or md5/sha1 checksums), raw magnetic
> recovery is better than nothing, if you're desperate.
> -cpghost.

I have used Spinrite several times with excellent results. In fact, I
recently used it to recover a Laptop drive that had become unusable.

Spinrite tries to turn off ECC if possible. It is not the cheapest
product; however, it works better than anything else I have tried on
bonked discs. Use it on its highest recover level and it will recover
the drive; although it may take a while.



Lord, defend me from my friends; I can account for my enemies.

        Charles D'Hericault
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