Re: [dm-crypt] can't open luks device after raid 5 rebuild

[Arno Wagner <arno@wagner.name>]

On Sun, Apr 08, 2012 at 06:23:22PM +0200, artificial11000 wrote:
> Hi,
> 
> as I noticed that I can't access the device, I recreated the raid manually.
>  mdadm --create --level=5 -n 3 /dev/md127 /dev/sdb /dev/sdc /dev/sdd
> 
> Could this damage the key-slot?
> Are the metadata of the RAID relevant to this?
> I read that old versions of mdadm created RAIDs with metadata=0.90
> and the newer versions with metadata=1.20.

This may be an additional problem or the only problem. Metadata 0.90 
is at the end of the device. Metadata 1.20 is 4k from the start of 
the device. The other versions are in still other places.
(I have no idea what messed up process created these thorougly
insane changes.)

So, yes, 4k offset is right in the first key-stripe. If so,
then your data is pemanently gone unless you have a header-backup.
In this case it is also possible that the array actually assembled
right and the problem is _only_ the new raid metadata block.

Arno

-- 
Arno Wagner, Dr. sc. techn., Dipl. Inform., CISSP -- Email: arno@wagner.name 
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----
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