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Re: Making an image of my HDD



> dd if=${device} conv=sync,noerror bs=64K | ssh -l ${user} ${host} "dd
> of=file.bin bs=64K"

Unless you need to encrypt, I recommend that you just use netcat
instead of ssh, as it will be faster.

I also recommend a larger block size.  Using a 64k block size will
take a long time, even if you take encryption out of the equation.

You should also boot from a Live CD; using dd to backup a mounted
filesystem can easily result in a corrupt backup image.  Off the top
of my head, I seem to remember Trinity Rescue Kit & Knoppix having
netcat, dd, and ssh.

The "noerror" conversion is unneccessary.  If dd is giving you input
errors, replace your hard drive and use dd_rescue to salvage your
data.  Also, I don't think you need to use the "sync" option in this
case.  I've never used it for my backups, and they have turned out
perfectly.

As long as you triple-check your if= and your of= before you hit enter
you shouldn't have any major issues. :-)

I also recommend you compress the image to save bandwidth and storage
space, although bzip2 has a 900k cap on its block size, so any larger
blocksizes passed to dd will be moot.

dd if=${device} bs=900k | bzip2 -9c | ssh -l ${user} ${host} "dd
of=backup.img.bz2"

Then verify the image.
on the laptop:
dd if=${device} bs=50M | md5sum

on the server:
bzip2 -d < backup.img.bz2 | md5sum

Someone please correct me if this is wrong.

-Elijah

--
http://elijahr.blogspot.com/


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