Re: Multiple disk failure, but slot numbers are corrupt and preventing assembly.

Leon Woestenberg wrote:

David,

thanks for all the advice so far.

No problem :)

In first instance we were searching for ways to tell mdadm what we
know about the array (through mdadm.conf) but from all advice we got
we have to take the 'usual' non-syncing-recreate approach.

We will try to make disk clones first. Will dd suffice or do I need
something more fancy that maybe copes with source drive read errors in
a better fashion?

ddrescue and dd_rescue are *much* better.

I favour the gnu ddrescue - it's much easier. But sometimes, on some kernels
with some hardware I've had kernel locks that dd_rescue (eventually, after many
minutes) times out from.

The RIP iso is a good place to start.
http://www.tux.org/pub/people/kent-robotti/looplinux/rip/

David