From mboxrd@z Thu Jan 1 00:00:00 1970 From: Joachim Otahal Subject: Re: BUG:write data to degrade raid5 Date: Fri, 19 Mar 2010 19:20:42 +0100 Message-ID: <4BA3C07A.8030204@gmx.net> References: Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: Sender: linux-raid-owner@vger.kernel.org To: jin zhencheng Cc: neilb@suse.de, linux-raid@vger.kernel.org, linux-kernel@vger.kernel.org List-Id: linux-raid.ids jin zhencheng schrieb: > hi; > > i use kernel is 2.6.26.2 > > what i do as follow: > > 1, I create a raid5: > mdadm -C /dev/md5 -l 5 -n 4 /dev/sda /dev/sdb /dev/sdc /dev/sdd > --metadata=1.0 --assume-clean > > 2, dd if=/dev/zero of=/dev/md5 bs=1M& > > write data to this raid5 > > 3, mdadm --manage /dev/md5 -f /dev/sda > > 4 mdadm --manage /dev/md5 -f /dev/sdb > > if i faild 2 disks ,then the OS kernel display OOP error and kernel down > > do somebody know why ? > > Is MD/RAID5 bug ? > RAID5 can only tolerate ONE drive to fail of ALL members. If you want to be able to fail two drives you will have to use RAID6 or RAID5 with one hot-spare (and give it time to rebuild before failing the second drive). PLEASE read the documentation on raid levels, like on wikipedia. Joachim Otahal