From mboxrd@z Thu Jan 1 00:00:00 1970 From: Martin Cracauer Subject: Re: replace disk in raid5 without linux noticing? Date: Sun, 23 Apr 2006 12:43:50 -0400 Message-ID: <20060423124350.B38675@cons.org> References: <200604191631.04305.Dexter.Filmore@gmx.de> <200604212023.30855.Dexter.Filmore@gmx.de> <17481.23502.962814.840550@fisica.ufpr.br> <20060422110816.A22573@cons.org> <17482.27751.358345.185741@fisica.ufpr.br> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <17482.27751.358345.185741@fisica.ufpr.br>; from carlos@fisica.ufpr.br on Sat, Apr 22, 2006 at 02:48:23PM -0300 Sender: linux-raid-owner@vger.kernel.org To: Carlos Carvalho Cc: Martin Cracauer , linux-raid@vger.kernel.org List-Id: linux-raid.ids Carlos Carvalho wrote on Sat, Apr 22, 2006 at 02:48:23PM -0300: > Martin Cracauer (cracauer@cons.org) wrote on 22 April 2006 11:08: > >> stop the array > >> dd warning disk => new one > >> remove warning disk > >> assemble the array again with the new disk > >> > >> The inconvenience is that you don't have the array during the copy. > > > >Stopping the array and restarting it as readonly will give you access > >to the data while that copy is in progress. > > Yes but then you could just switch it to read-only without stopping. I believe that would be fine to do the whole operation. Filesystem read-only, then md read-only, copy disk, then you need to unmount and stop the md to restart it with the new disk. If the final disk change involves a powerdown and putting the new disk on the physical interface that the old one was on it should be transparent. %% BTW, last time I tested a Linux software RAID-5 by ripping out an active disk I noticed that while the filesystem stayed up and usable, a currently ongoing system call would not return and block forever. Is that a know behaviour? Martin -- %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% Martin Cracauer http://www.cons.org/cracauer/ FreeBSD - where you want to go, today. http://www.freebsd.org/