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Date: Tue, 11 Dec 2012 15:46:19 +0100
From: Erik Logtenberg <erik@logtenberg.eu>
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Subject: [dm-crypt] How to increase key size of existing volume
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Dear list,

I have been using luks for quite some time, and as a result I have
several luks volumes in use that are still based on 128 bits key sizes.
Current default in Fedora is already upped to 256 bits and RSA even
advices key sizes of 1024 or even 2048 for highly secure stuff.

So, how do I increase the key size? In man cryptsetup I see that the
--key-size option only applies to the create, luksFormat and loopaesOpen
commands. Is there any way I can make this happen?

Thanks,

Erik Logtenberg.