From mboxrd@z Thu Jan 1 00:00:00 1970 From: Kasper Dupont <55666323303470176297@expires.05.sep.2006.kasperd.net> Subject: Re: No syncing after crash. Is this a software raid bug? Date: Sat, 4 Mar 2006 20:50:35 +0100 Message-ID: <20060304195032.GA12786@hactar.lan> References: <20060301124432.GA3591@hactar.lan> <20060301215641.GA27042@hactar.lan> <20060303073016.GA662@hactar.lan> <20060303144824.GA15672@hactar.lan> <20060304131609.GA4064@erwin.lan> Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: Content-Disposition: inline In-Reply-To: <20060304131609.GA4064@erwin.lan> Sender: linux-raid-owner@vger.kernel.org To: linux-raid@vger.kernel.org List-Id: linux-raid.ids > However, since "inconsistent parity information in raid[456] is equal > to "different mirrors" in raid1, there is no real difference. There is a major difference. Inconsistent parity information can eventually lead to corruption in another sector in the stripe. Assume there are two data disks and one parity disk, and two different versions of sector A are used. Then after a write you would end up with: A B A'+B on the three disks. This is a problem even if you are never going to need the data from A again. If the disk holding B dies it will be reconstructed as (A)+(A'+B), which does not give B as it should. So after reconstruction sector B is corrupted. --=20 Kasper Dupont -- Rigtige m=E6nd skriver deres egne backupprogrammer #define _(_)"d.%.4s%."_"2s" /* This is my new email address */ char*_=3D"@2kaspner"_()"%03"_("4s%.")"t\n";printf(_+11,_+6,_,6,_+2,_+7,= _+6); - To unsubscribe from this list: send the line "unsubscribe linux-raid" i= n the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html