From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from localhost (localhost [127.0.0.1]) by mail.saout.de (Postfix) with ESMTP id 31E6F8F8C for ; Fri, 31 Jul 2009 11:12:46 +0200 (CEST) Received: from mail.saout.de ([127.0.0.1]) by localhost (mail.saout.de [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id jsHucJqtftS8 for ; Fri, 31 Jul 2009 11:12:41 +0200 (CEST) Received: from ichtualles.schintech.net (ichtualles.schintech.net [87.230.1.161]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by mail.saout.de (Postfix) with ESMTPS for ; Fri, 31 Jul 2009 11:12:41 +0200 (CEST) From: Wolfgang Schindler Date: Fri, 31 Jul 2009 11:12:38 +0200 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="Boundary-00=_GWrcKjQZjgpZTci" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200907311112.38952.schindler@schintech.net> Subject: [dm-crypt] Questions about LUKS on RAID5 List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: christophe@saout.de Cc: dm-crypt@saout.de --Boundary-00=_GWrcKjQZjgpZTci Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Hello out there, sunny greetings from good old germany, Don't know if i'm in the right place here. I need some help as it's a black doomed day, today, things went wrong as they sometimes do....... For a real long time i had two running RAID5's with LUKS encrypted data on them. I had to change the system, so i setup a new machine, with two new raid5's also encrypted with LUKS, of course with some more data space. I sent the data over network. Anything worked fine for some days. Now my system disk crashed. So i took another system disk from another raid system and started up. One of the data raids was found immediately and i could luksOpen it with my passphrase, the other one could not be assembled. I tried some assembles with --force and --scan. Did not work. Now I had a real bad idea, late at night and lot's of other things to do asides. I zeroed the superblocks of the devices belonging to the raid that could not be assembled. I rebuilt the raid with the same parameters as before and it was rebuilt. The raid was then found immediately. No problems until there, but when i was trying to luksOpen the raid, my passphrase did not work. So i checked the sourcecode of cryptsetup-1.0.7 and saw that in function LUKS_generate_phdr the UUID of the underlying Raid or Device is used in some way. But, by recreating the RAID, the UUID of the RAID has changed. So far so bad. Question 1: is this UUID used in any way for decryption? Question 2: Would it be a reasonable and walkable way to set back the UUID to the older one (thanks God or whomever, it was noticed in the old mdadm.conf) to get the decryption running again? Question 3: Do you know how to set back the UUID? Thanks for answering, otherwise my good datastuff was gone?? and i had a real bad day. Cheers -- Wolfgang Schindler --Boundary-00=_GWrcKjQZjgpZTci Content-Type: text/html; charset="utf-8" Content-Transfer-Encoding: 7bit Hello out there, sunny greetings from good old germany,


Don't know if i'm in the right place here. I need some help as it's a black doomed day, today, things went wrong as they sometimes do.......
For a real long time i had two running RAID5's with LUKS encrypted data on them. I had to change the system, so i setup a new machine, with two new raid5's also encrypted with LUKS, of course with some more data space. I sent the data over network. Anything worked fine for some days.
Now my system disk crashed. So i took another system disk from another raid system and started up. One of the data raids was found immediately and i could luksOpen it with my passphrase, the other one could not be assembled.
I tried some assembles with --force and --scan. Did not work.
Now I had a real bad idea, late at night and lot's of other things to do asides. I zeroed the superblocks of the devices belonging to the raid that could not be assembled.
I rebuilt the raid with the same parameters as before and it was rebuilt. The raid was then found immediately.
No problems until there, but when i was trying to luksOpen the raid, my passphrase did not work.
So i checked the sourcecode of cryptsetup-1.0.7 and saw that in function LUKS_generate_phdr the UUID of the underlying Raid or Device is used in some way.
But, by recreating the RAID, the UUID of the RAID has changed. So far so bad.


Question 1:
is this UUID used in any way for decryption?
Question 2:
Would it be a reasonable and walkable way to set back the UUID to the older one (thanks God or whomever, it was noticed in the old mdadm.conf) to get the decryption running again?
Question 3:
Do you know how to set back the UUID?


Thanks for answering, otherwise my good datastuff was gone?? and i had a real bad day.


Cheers
--
Wolfgang Schindler


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