Re: [dm-crypt] Expanding a LUKS partition to a second drive.

From: Arno Wagner <arno@wagner.name>
To: dm-crypt@saout.de
Subject: Re: [dm-crypt] Expanding a LUKS partition to a second drive.
Date: Wed, 12 Feb 2020 17:48:23 +0100	[thread overview]
Message-ID: <20200212164823.GA29788@tansi.org> (raw)
In-Reply-To: <CAE3N1D+_pZNQGwi8O4dP3c_Hv8PMGkqYHieqTsrfXEi0d1_HGQ@mail.gmail.com>

Hi James,

to be safe, you need to do this with a full backup of the data 
in the LUKS container anyways.
Hence easisest is probably 

backup->make new partition->restore.

The LUKS container itself has no size information, it will 
fill the new parition. For the filesystem, you need to either
backup the LUKS container as ibinary mage and extend the 
filesystem in it after restore, or backup on file-level and 
create a new LUKS container and filesystem in it.

Luks does nto care whther the partition is native or LVM
(or NBD, or whatever).

Regards,
Arno

On Tue, Feb 11, 2020 at 20:21:55 CET, James Dehnert wrote:
>    Greetings dm-crypt group,
>    I have a situation where I have an existing LUKS encrypted partition
>    (root) and the user wants to expand that partition onto a second drive.
>    The existing partition was created at configuration as part of the
>    Ubuntu preseed setup.
>    I know how to do this with LVM, but I'm not sure if this can be done
>    without backing up all the data, and then rebuilding the system from
>    scratch.
>    I'm not sure where the LUKS volume is created in respect to LVM.  I
>    can't tell if its created directly on the physical volume, on the
>    volume group, or on the logical volume, so I'm noy sure where I should
>    be looking to expand the substrate.  Or if this is even possible.
>    Any assistance would be greatly appreciated, even if its just "It can't
>    be done".
>    —
>    Thanks,     James "Zeke" Dehnert
>      Zeke Dehnert
>      Senior Linux IT Engineer
>      Cruise LLC
>      [1]zeke.dehnert@getcruise.com
> 
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> References
> 
>    1. mailto:zeke.dehnert@getcruise.com

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-- 
Arno Wagner,     Dr. sc. techn., Dipl. Inform.,    Email: arno@wagner.name
GnuPG: ID: CB5D9718  FP: 12D6 C03B 1B30 33BB 13CF  B774 E35C 5FA1 CB5D 9718
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