On Tue, 22 Mar 2011 17:42:33 +0100 A J Wyborny <ajwyborny@xxxxxxxxx> wrote: > Wow, thank you so much. I forgot to mention that I AM running mdadm > v3.1.4, compiled from source, after initially running the Ubuntu > default of 2.6.7.1. I'm not sure why the "start_dirty_degraded" file > wasn't updated, but I'm glad I know about it now. I thought it was fixed in 3.1.4... apparently not quite. Your particular case was a bit unusual and slip through the tests. I've added a fix which will be in 3.1.5 and 3.2.1. 'start_dirty_degraded' is only intended to be used when arrays are auto-assembled by the kernel (a practice that I don't encourage). I suggested it's use here as a work around for the bug in mdadm rather than the appropriate way to generally deal with your situation. It won't be needed in future mdadm releases. Thanks, NeilBrown > > My attempts to re-add /dev/sda1 to the array right away failed, but a > reboot took care of that problem and it's now recovering. > > Again, I really appreciate it. > > Adam > > On Mon, Mar 21, 2011 at 11:28 PM, NeilBrown <neilb@xxxxxxx> wrote: > > On Mon, 21 Mar 2011 23:08:40 +0100 A J Wyborny <ajwyborny@xxxxxxxxx> wrote: > > > >> Hi all, > >> > >> 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. My initial problem, I've > >> determined, was caused by a faulty PCI-E SATA controller card. I > >> would constantly lose access to my mounted RAID volume (/home) at > >> random times and increasingly during high write accesses. In the past > >> a reboot and running "mdadm --assemble --force --scan" would solve the > >> issue. This time, no such luck. In the process of troubleshooting I > >> also fat-fingered an "mdadm --assemble" command and lost the > >> superblock of my /dev/sda1 partition, which isn't helping things > >> either. > >> > >> The SMART status is clean on all disks. > >> > >> I really appreciate any thoughts/input you might have. -Adam > >> > >> Here's my setup: > >> > >> 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 > >> > >> Results: > >> root@focalor:~# cat /proc/mdstat > >> Personalities : [linear] [multipath] [raid0] [raid1] [raid6] [raid5] > >> [raid4] [raid10] > >> unused devices: <none> > >> 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 > > > > http://neil.brown.name/git?p=mdadm;a=commitdiff;h=4e9a6ff778cdc58dcc6897e74cf5ee1d3f73e1f7 > > > > 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 > >> > >> mdadm -E output: > >> http://pastebin.com/vnaamC75 > > > > It is OK - even encouraged - to include this content directly in the Email. > > 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" in > > the body of a message to majordomo@xxxxxxxxxxxxxxx > > More majordomo info at http://vger.kernel.org/majordomo-info.html > > > -- > To unsubscribe from this list: send the line "unsubscribe linux-raid" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html -- -- To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
