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From: Robert Nichols <rnicholsNOSPAM@comcast.net>
Date: Sat, 01 Feb 2014 17:33:27 -0600
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References: <52ED5E0B.3090300@mthode.org> <20140201213444.GA6778@tansi.org>
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Subject: Re: [dm-crypt] cryptsetup luksFormat with the size option
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To: dm-crypt@saout.de

On 02/01/2014 03:34 PM, Arno Wagner wrote:
> On Sat, Feb 01, 2014 at 21:50:19 CET, Matthew Thode wrote:
>> Am I correct in stating that setting --size=8 will make the sectors 4k
>> in size?  Also, how can I check what existing luks volumes are set to?
>>
>> --
>> -- Matthew Thode
>>
>
> No, you are not. As the man-page clearly states, this sets the
> size of the underlying device as multiple of 512B sectors.

I submit that for the luksFormat action, the --size option does _nothing_!
The size is not recorded in the LUKS header, and luksFormat does not open
the encrypted device, so there is neither a temporary nor a persistent
effect from that option. In fact, there is not even a check that the
requested size is within the limits of the underlying device.

-- 
Bob Nichols     "NOSPAM" is really part of my email address.
                 Do NOT delete it.