Mounting/examining dd image?

John Nielsen lists at
Fri Nov 2 22:22:33 PDT 2007

On Friday 02 November 2007, Jon Drukman wrote:
> I was trying to transplant my system from a small, old drive to a big,
> new one.  I made a dd dump of the entire small drive, but then I
> accidentally destroyed the drive (be careful with bare drives and
> metal PC cases...)
> Anyway, I have the dd file but I don't have a spare drive onto which
> to copy it.  Is there a way to read its contents/mount it/explore
> it/hopefully extract files from it on a running system?

Yes there is:

mdconfig -a -t vnode -f "/path/to/dd/image/file"

That will cause the file to be treated as an md device. See also man 
mdconfig. The output of that command is the newly created /dev/md? device 
node. Depending on whether you dumped the whole disk, a slice, or a 
partition there may be additional devices. If you dd'ed the whole disk your 
former root partition might show up as /dev/md0s1a, for example.

Once you've identified the device node(s) that contain(s) the filesystem(s) 
you're interested in, just mount it/them like you would any other device, 
	mount /dev/md0s1a /mnt


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