Program to copy data from a bad disk?

[LI Xin]

Hi,

Recently my hard drive goes bad again, which has a lot of bad sectors 
for unknown reasons.  I am looking for some software that is capable of 
doing a sector-to-sector copy of the hard drive.

I have tried dd but with conv=noerror,sync it would just fill 0's for 
the whole block size (say, in order to get best speed you will want 
bs=128k or even larger, but that means that you will lose data  when 1 
of these 256 sectors is bad).  Is there any program that is smarter 
which do a sector-to-sector copy for these failed blocks and use larger 
transfer buffer for others?

Cheers,
-- 
Xin LI <delphij at delphij.net>	http://www.delphij.net/
FreeBSD - The Power to Serve!

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