Thank you for your quick and clear answer Milan! Tha'ts really great! :D

So, in the case of such a header destruction by an "old" OS, I think it
is still possible to restore the header I saved using

_luksHeaderBackup_ <device> --header-backup-file <file>

doing

_luksHeaderRestore_ <device> --header-backup-file <file>

Correct?

Best regards,

Patrick



Le 19. 06. 11 16:53, Milan Broz a écrit :
> On 06/19/2011 03:54 PM, Patrick wrote:
>> The case : I want to encrypt a full USB disk and my question is : is
>> it mandatory to have a partition existing on the device and to
>> luskformat the partition? In other words, is it OK to luksformat the
>> full device, without mentionning any partition? Is it off
>> "standards"?
> You can use whole device without partition table, there is no problem
> in Linux. For LUKS it is just block device - it is not important
> if it is partition or the whole device.
>
> There is only one situation, I know about, when using partition is safer.
>
> If you have portable disk (or USB flashdrive or whatever) and there
> is no partition table on it, and you plug such drive to
> another system (namely older version of Windows) it
> likes to offer you to "initialize" drive - which can destruct
> LUKS header there. If there is a partition table, it thinks that
> drive was already initialized preventing it.
> (I think it is not problem in recent versions but not sure.)
>
> Milan