From mboxrd@z Thu Jan 1 00:00:00 1970 From: Gabor Gombas Subject: Re: Swapping a disk without degrading an array Date: Sun, 31 Jan 2010 17:33:55 +0100 Message-ID: <20100131163355.GA25622@twister.home> References: <1264421475.30742.49.camel@test.apertos.eu> <20100129221904.439e2afe@notabene> <87tyu4zzxo.fsf@frosties.localdomain> <4B65A2EB.1000506@shiftmail.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <4B65A2EB.1000506@shiftmail.org> Sender: linux-raid-owner@vger.kernel.org To: Asdo Cc: Goswin von Brederlow , linux-raid , Neil Brown List-Id: linux-raid.ids On Sun, Jan 31, 2010 at 04:34:03PM +0100, Asdo wrote: > 1/ The live-spare gets filled of data without recording anything on > any superblocks. If there is a power failure and reboot, the new MD > will know nothing about this. The process has to be restarted. IMHO MD must know about the copy and it must know not to use the new device before the copying is completed. Otherwise after a reboot mdadm may either import the new half-written spare instead of the real one if the superblock is already copied, or other tools like LVM may start using the new half-written spare instead of the RAID if the MD superblock is still missing. Gabor -- --------------------------------------------------------- MTA SZTAKI Computer and Automation Research Institute Hungarian Academy of Sciences ---------------------------------------------------------