From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Greaves Subject: Re: mdadm create to existing raid5 Date: Fri, 13 Jul 2007 11:32:16 +0100 Message-ID: <469754B0.4020104@dgreaves.com> References: <200707122318.l6CNIao08247@www.watkins-home.com> <469736E2.7040802@dgreaves.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <469736E2.7040802@dgreaves.com> Sender: linux-raid-owner@vger.kernel.org To: 'Jon Collette' Cc: Guy Watkins , linux-raid@vger.kernel.org List-Id: linux-raid.ids David Greaves wrote: > For a simple 4 device array I there are 24 permutations - doable by > hand, if you have 5 devices then it's 120, 6 is 720 - getting tricky ;) Oh, wait, for 4 devices there are 24 permutations - and you need to do it 4 times, substituting 'missing' for each device - so 96 trials. 4320 trials for a 6 device array. Hmm. I've got a 7 device raid 6 - I think I'll go an make a note of how it's put together... Have a look at this section and the linked script. I can't test it until later http://linux-raid.osdl.org/index.php/RAID_Recovery http://linux-raid.osdl.org/index.php/Permute_array.pl David