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Re: Problem using dd to clone a hard disk with bad sectors.

Subject: Re: Problem using dd to clone a hard disk with bad sectors.
Date: Sun, 19 Feb 2006 18:27:05 +0000
Hi,

I'm trying to properly clone a 4.3GB (it's old, I know) hard disk which unfortunately has a lot of bad sectors.
I am using Helix 1.7 as an operating environment, not mounting the old drive at all.
I used the command:


dd if=/dev/hdb of=/mnt/hda7/image.dd conv=noerror,sync

My problem is that the md5 hash of the image file is different from that of the original HD (acquired via the command: dd if=/dev/hdb conv=noerror,sync | md5sum > /mnt/hda7/orig_disk_md5sum.txt) [etc]

You might need to specify obs=<something>. If dd uses different output block sizes in the two cases the amount of padding in the last block will be different and so will the digest.



-- Bob Bishop +44 (0)118 940 1243 rb@gid.co.uk fax +44 (0)118 940 1295

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