Hi all- I recently created a RAID1 2 disk mdadm array /dev/md1 with 1.2 metadata on a Ubuntu system that has 3 other mdadm arrays running on it. The power went out at my house last night, and I rebooted the system when it came back up. When it came back up, my new array was in two pieces /dev/md126 and /dev/md127 (with incorrect members, showing 1 active drive, 1 spare in each). I rebooted again, and had what appeared to be my working array, but showing up under /dev/md127. I could stop and do a --scan to assemble it correctly as /dev/md1, but when I rebooted again I got the same results with 126 and 127. My mdadm.conf was correct. I did some searching on my archives of this list, and found a solution as follows: ----------- How to fix the '125/126/127' mdadm issue. The array has '125' stored as the 'preferred minor' in the metadata. You can change this by assembling with --update=super-minor. e.g. mdadm -S /dev/md125 mdadm -A /dev/md1 --update=super-minor it should get details of which devices to included from /etc/mdadm.conf. However it is possible that mdadm.conf in your initrd also the name as /dev/md125. So once you have performed the above, run mkinitrd again, reboot, and report what happens. ---------------- I had to run the above commands, and then make sure I ran update-initramfs -v -u for it to stick after reboot. My issue is solved, but I would like to understand what the root cause is, and why the above solution worked. Can someone elaborate on what super-minor is? This is a home system and I had backups so I was comfortable trying the above, but I don't typically like running commands on faith I don't understand fully, especially in Linux. Can anyone shed some light on this? I can provide further OS and array details if necessary, but it sounds like this issue has occurred for others in the past. Thanks. -- 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
