From mboxrd@z Thu Jan 1 00:00:00 1970 From: NeilBrown Subject: Re: RAID-5 and mdadm --assemble troubleshooting Date: Tue, 22 Mar 2011 09:28:08 +1100 Message-ID: <20110322092808.31d545c6@notabene.brown> References: Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: Sender: linux-raid-owner@vger.kernel.org To: A J Wyborny Cc: linux-raid@vger.kernel.org List-Id: linux-raid.ids On Mon, 21 Mar 2011 23:08:40 +0100 A J Wyborny wr= ote: > Hi all, >=20 > After exhausting my efforts with google searches and linux-raid IRC > chats, I'm reaching out to you all for some help with why I can't > assemble a broken RAID-5 configuration. =A0My initial problem, I've > determined, was caused by a faulty PCI-E SATA controller card. =A0I > would constantly lose access to my mounted RAID volume (/home) at > random times and increasingly during high write accesses. =A0In the p= ast > a reboot and running "mdadm --assemble --force --scan" would solve th= e > issue. =A0This time, no such luck. =A0In the process of troubleshooti= ng I > also fat-fingered an "mdadm --assemble" command and lost the > superblock of my /dev/sda1 partition, which isn't helping things > either. >=20 > The SMART status is clean on all disks. >=20 > I really appreciate any thoughts/input you might have.=A0 -Adam >=20 > Here's my setup: >=20 > RAID-5 array with four 1.5TB disks (/dev/sda1, /dev/sdb1, /dev/sdd1, = /dev/sde1) > /dev/sdc is my root and swap partitions > /dev/md0 should be mounted to /home >=20 > Results: > root@focalor:~# cat /proc/mdstat > Personalities : [linear] [multipath] [raid0] [raid1] [raid6] [raid5] > [raid4] [raid10] > unused devices: > root@focalor:~# mdadm -vv --assemble --force --scan > mdadm: looking for devices for /dev/md0 > mdadm: cannot open device /dev/sdc1: Device or resource busy > mdadm: /dev/sdc1 has wrong uuid. > mdadm: no RAID superblock on /dev/sda1 > mdadm: /dev/sda1 has wrong uuid. > mdadm: /dev/sde1 is identified as a member of /dev/md0, slot 3. > mdadm: /dev/sdd1 is identified as a member of /dev/md0, slot 2. > mdadm: /dev/sdb1 is identified as a member of /dev/md0, slot 1. > mdadm: no uptodate device for slot 0 of /dev/md0 > mdadm: added /dev/sdd1 to /dev/md0 as 2 > mdadm: added /dev/sde1 to /dev/md0 as 3 > mdadm: added /dev/sdb1 to /dev/md0 as 1 > mdadm: failed to RUN_ARRAY /dev/md0: Input/output error You are hitting an mdadm bug fixed in 2.6.9 by=20 http://neil.brown.name/git?p=3Dmdadm;a=3Dcommitdiff;h=3D4e9a6ff778cdc58= dcc6897e74cf5ee1d3f73e1f7 What version of mdadm are you running? You can work around it by echo 1 > /sys/module/md_mod/parameters/start_dirty_degraded before running the 'mdadm -A' command. > dmesg output: > http://pastebin.com/usrzvmpn >=20 > mdadm -E output: > http://pastebin.com/vnaamC75 It is OK - even encouraged - to include this content directly in the Em= ail. That makes it easier to reference in a reply, should that be helpful. NeilBrown -- 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