From: Matthias Schniedermeyer <ms@citd.de>
To: yakamo <yakamo@drahony.com>
Cc: dm-crypt@saout.de
Subject: Re: [dm-crypt] luks header
Date: Wed, 7 Jan 2015 12:31:38 +0100 [thread overview]
Message-ID: <20150107113138.GA7265@citd.de> (raw)
In-Reply-To: <20150106192300.2f61d3770e06705a9a52afc1@drahony.com>
On 06.01.2015 19:23, yakamo wrote:
> can you recommend an effective way to remove the luks header?
> i have tried cryptsetup luksFormat /dev/xxx --header ~/headerfile align-payload=0 but this still writes a header to the encrypted drive, is meant to happen?
From the man-page of a new enough version of cryptsetup:
- snip -
erase <device>
luksErase <device>
Erase all keyslots and make the LUKS container permanently inaccessible. You do not need to provide any password for this operation.
WARNING: This operation is irreversible.
- snip -
Altough the warning is only 99% true, restoring a Header-Backup makes
the device accessible again, but you would need to have made a Backup
beforehand.
or just
dd if=/dev/zero of=/dev/<device> bs=1M count=100
Which erases the first 100MB of said device, the LUKS-Header is only a
fraction of that, so this command also damages the data/filesystem
inside the container!
For total erasure of the device/patition kjust leave out "count=100" and
--
Matthias
prev parent reply other threads:[~2015-01-07 11:31 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-01-06 19:23 [dm-crypt] luks header yakamo
2015-01-07 11:31 ` Matthias Schniedermeyer [this message]
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