Help recovering a RAID set

[Liam Proven]

The RAID in one of my servers died. Sadly, so did the disk with the
backup on it when I tried to recover it. As did the disk in my desktop
with another backup of all the important files.

So, I am trying to recover the data.

I used gddrescue to get image copies of the 4 × 40GB drives; they are
on a 300GB drive, as partitions sdb5, sdb6, sdb7 and sdb8.

I am trying to assemble them with mdadm but it reports that there's no
superblock on any of them.

Looking at the raw partitions with a hex editor, I can see that there
are large slices of empty space at the start of each drive.

On sdb5 and sdb6, the data starts at 0xB0000. On sdb7 and sdb8 it
starts at 0xAA000.

Can anyone suggest how I can prune off the first  720896 bytes of the
first 2 partitions and the first 696320 bytes of the second 2?

I have other spare drives - I could in principle `dd` the whole
partitions onto other media, but I am not fluent enough in dd to skip
the first $number blocks...

-- 
Liam Proven • Profile: http://lproven.livejournal.com/profile
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