From mboxrd@z Thu Jan 1 00:00:00 1970 From: Neil Brown Subject: Re: deleting mdadm array? Date: Thu, 25 Oct 2007 20:12:02 +1000 Message-ID: <18208.27634.262419.581091@notabene.brown> References: <20071025100619.3b3810be@absurd> <47206820.4020005@dgreaves.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: message from David Greaves on Thursday October 25 Sender: linux-raid-owner@vger.kernel.org To: David Greaves Cc: Janek Kozicki , linux-raid@vger.kernel.org List-Id: linux-raid.ids On Thursday October 25, david@dgreaves.com wrote: > I think the only time you need to 'delete' an array before creating a new one is > if you change the superblock version since it quietly writes different > superblocks to different disk locations you may end up with 2 superblocks on the > disk and then you get confusion :) > (I'm not sure if mdadm is clever about this though...) > Mdadm tries to be clever. When creating an array, it zeros any superblocks that it finds on the array in any of the expected locations. And when guessing the metadata format used, if it find two or more, it chooses the one with the more recent create timestamp. NeilBrown