From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S935937AbYEBWFT (ORCPT ); Fri, 2 May 2008 18:05:19 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1758710AbYEBWFE (ORCPT ); Fri, 2 May 2008 18:05:04 -0400 Received: from web50212.mail.re2.yahoo.com ([206.190.39.176]:36293 "HELO web50212.mail.re2.yahoo.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1755587AbYEBWFD convert rfc822-to-8bit (ORCPT ); Fri, 2 May 2008 18:05:03 -0400 DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=s1024; d=yahoo.com; h=X-YMail-OSG:Received:X-Mailer:Date:From:Reply-To:Subject:To:Cc:In-Reply-To:MIME-Version:Content-Type:Content-Transfer-Encoding:Message-ID; b=ig7gxUCGItaoVjoKZqEGh0sn2VWhg4rx74RF8BijVkpZMg0FtwzW79e3WuMZDJ40VhpT/eBWtIGXfH2C07sR+hKLwwxy4Ay/3DV2/7yEOTVuPo+E4B+Pq80oJeYgfKOco10WSjJZdwXxHfVuecmbRFxetKrniJEGbxF8SU7Neyo=; X-YMail-OSG: WezsH.IVM1k4e4bgxCXqnErtbjR35Z39s69lZitLetCzJmJHE_R3Fi3UfXiB7jQ.sz.EJlyJkn5.o22RcXIqMAhUsNCeAy06wUWNkGIC5fzKm5isuDCljA-- X-Mailer: YahooMailWebService/0.7.185 Date: Fri, 2 May 2008 15:04:55 -0700 (PDT) From: Alex Davis Reply-To: alex14641@yahoo.com Subject: Re: Sharing disks amoung multiple software RAIDs To: David Greaves , Kasper Sandberg Cc: David Rees , David Lethe , Justin Piszcz , linux-raid@vger.kernel.org, linux-kernel@vger.kernel.org In-Reply-To: <1209764630.7827.15.camel@localhost> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: 8BIT Message-ID: <977930.28629.qm@web50212.mail.re2.yahoo.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --- On Fri, 5/2/08, Kasper Sandberg wrote: > From: Kasper Sandberg > Subject: Re: Sharing disks amoung multiple software RAIDs > To: "David Greaves" > Cc: "David Rees" , "David Lethe" , alex14641@yahoo.com, "Justin Piszcz" , linux-raid@vger.kernel.org, linux-kernel@vger.kernel.org > Date: Friday, May 2, 2008, 5:43 PM > On Fri, 2008-05-02 at 09:25 +0100, David Greaves wrote: > > Kasper Sandberg wrote: > > > Im not treating it as a backup, what i want, is > to make sure that if 1 > > > disk dies, the data is still intact and ill > hopefully be able to run > > > with 1 disk till the newly ordered one arrives > > Probably one of the main design objectives behind > RAID/md > > Exactly, but once people start saying: "Look how many > problems people > post to the thread on > a weekly basis where people lose their data when md > rebuilds go bad with > non-shared disks" i begin to worry.. > > > > > > So my question remains.. Is md raid1 not suited > for this need? would it > > > be safer to run in non-raid1 mode and daily(maybe > hourly) rsync > > > everything over to the second disk? > > > > md is 100% guaranteed perfect or your money back... > > rsync is 100% guaranteed perfect or your money back... > > your backups are 100% guaranteed perfect or your money > back... > > your hard drives are 100% guaranteed perfect or your > money back... > > your CPU and RAM are 100% guaranteed perfect or your > money back... > > your CPU and PSU fans are 100% guaranteed perfect or > your money back... > > > > Clearly if you want to panic over reliability you have > lots of choices :) > > I do not wish to panic, i merely wished to know if linux MD > is believed > to work in most cases, or believed to do all sorts of weird > stuff when > resyncing :) > > > > > David > > PS, FWIW md has saved my data* countless times over > the past 'n' years in > > exactly the scenario you describe. > > It has also been useful to people i know, i just wished to > be sure :) > and as Keld Jørn Simonsen and Helge Hafting's comments > seems to confirm, > linux md IS nice and stable :) > > and as said, what im looking for isnt an in-box backup > solution, merely > safety in case one disk burns :) > > > > > *(or more accurately has saved me from having to > restore my data) Just to add another data point, I've been using md in RAID 5 configuration for ~3 years with dedicated USB and SATA disks (not mixed) and have had disks go bad, and have yet to lose any data. Given the 'quality' of high-capacity disks nowadays, RAIDing them is the right thing to do. ____________________________________________________________________________________ Be a better friend, newshound, and know-it-all with Yahoo! Mobile. Try it now. http://mobile.yahoo.com/;_ylt=Ahu06i62sR8HDtDypao8Wcj9tAcJ