Bill Davidsen wrote:

Neil Brown wrote:

quoted

On Saturday December 23, davidsen@tmr.com wrote:
 

quoted

I hope I can use the md code to solve a problem, although in a way 
probably not envisioned by the author(s).

I have a disk image, a physical dump of every sector from start to 
finish, including the partition table. What I hope I can do is to 
create a one drive RAID-1 partitionable array, and then access it 
with fdisk or similar. These partitions are not "nice" types such as 
FAT, VFAT, ext2, etc, this is an odd disk, and I "saved it" by 
saving everything. Now I'd like to start dismembering the 
information and putting it into useful pieces. I even dare to hope 
that I could get the original software running on a virtual machine 
at some point.

The other alternative is to loopback mount it, I'm somewhat 
reluctant to do that if I can avoid it.

Yes, the partition table is standard in format if not in content.
    

Maybe...
Is this image in a file?
md only works with block devices, so you would need to use the 'loop'
driver to create a block-device "/dev/loopX".
  

I was thinking nbd, actually.

quoted

But as loop devices cannot be partitioned, you could then
  mdadm -Bf /dev/md/d9 -amdp8 -l1 -f -n1 /dev/loopX
  and then look at the partitions in /dev/md/d9_*

Should work.

Sounds worth a try. Will be a learning experience if nothing else.

Rather than setup nbd I did try a loop mount, and the whole process 
worked flawlessly. I was able to look at partitions, read the partition 
table, and generally do anything I could from a device. It worked so 
well I backed it up as an image, just in case I ever want to do 
something else with it.

Many thanks.

-- 
bill davidsen [off-list ref]
  CTO TMR Associates, Inc
  Doing interesting things with small computers since 1979