On 01/30/2014 05:16 AM, Wilson Jonathan wrote:
On Wed, 2014-01-29 at 23:49 -0500, Chris Schanzle wrote: <snip, as my reply might be relevent, or not> Two things come to mind, the first is if you updated the mdadm.conf (/etc/mdadm/mdadm.conf or /etc/mdadm.conf) The second is, update-initramfs -u to make sure things are setup for the boot process. (I tend to do this when ever i change something that "might" change a boot process... even if it does not, its pure habit as apposed to correct procedure)
Thanks for these suggestions. Fedora's /etc/mdadm.confshouldn't be necessary to start the array (yes for mdadm monitoring): this is not a boot device and the kernel was finding the lone single late-added parity disk on boot. As for updating the initramfs, it didn't make sense to try this as the late-added parity disk was being discovered so the kernel modules were available. It seems update-initramfs is for Ubuntu, for Fedora it's dracut. BTW, rebooting with (the non-hostonly) rescue kernel made no difference; it could have since the original install was on a non-raid device so it has no reason to include raid kernel modules. I got inspiration from https://raid.wiki.kernel.org/index.php/RAID_superblock_formats to switch superblock format from 1.2 (4k into the device) to the beginning of the device. Success! Precisely what I did after a reboot, starting/recreating md0 as mentioned previously: mdadm --detail /dev/md0 vgchange -an mdadm --stop /dev/md0 # supply info from above 'mdadm --detail' to parameters below mdadm --create /dev/md0 --assume-clean --level=5 --raid-devices=5 --chunk=512 --layout=left-symmetric --metadata=1.1 /dev/sd{a,b,c,d,e} At this point I had an array with a new UUID, could mount stuff, see data, all was good. mdadm --detail --scan >> /etc/mdadm.conf emacs !$ # commented out the previous entry cat /etc/mdadm.conf #ARRAY /dev/md0 metadata=1.2 name=d130.localdomain:0 UUID=011323af:44ef25e9:54dccc7c:b9c66978 ARRAY /dev/md0 metadata=1.1 name=d130.localdomain:0 UUID=6fe3cb23:732852d5:358f8b9e:b3820c6b Rebooted and my array was started! cat /proc/mdstat Personalities : [raid6] [raid5] [raid4] md0 : active raid5 sdc[2] sdb[1] sda[0] sdd[3] sde[4] 15627548672 blocks super 1.1 level 5, 512k chunk, algorithm 2 [5/5] [UUUUU] bitmap: 0/30 pages [0KB], 65536KB chunk I believe there is something broken with having a gpt-labeled disk (without partitions defined) that is incompatible with superblock version 1.2. -- 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
