Re: [dm-crypt] LUKS encrypted hard disk crashed. Recovery question

[Arno Wagner <arno@wagner.name>]

Hi Saibal,

On Fri, Aug 19, 2016 at 13:45:21 CEST, Saibal Kumar Adhya wrote:
>    [saibal] Thanks a lot Michael.
>    > If you are able to somehow gain access to the key slots in the LUKS
>    > header, it should be possible to decrypt the (stored) payload data,
>    to
>    > the extent that the data recovery agency was able to recover the
>    data.
>    > What they were not able to recover will decrypt to nonsense.
> 
>    [saibal] I have couple of following question.
> 
>    1) Is there a way to know, if the key slot area in the LUKS header has
>    been recovered or not? How to recover the entire partition from there?

Try a LuksOpen. It does not care about filesystem damage, but it
will obnly work if header and keyslot are undamaged.

>    2) This question is for my information. As I understand, LUKS header
>    and "key-slot" are very very critical. So, if any of these sectors get
>    damaged then the entire partition is un-usable. Is there a backup copy
>    of LUKS header and key slots, kept within the partition itself?
>    Thanks in advance.

No. You have to do such a backup yourself. See most of FAQ Section 6:
https://gitlab.com/cryptsetup/cryptsetup/wikis/FrequentlyAskedQuestions

Regards,
Arno

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