I just ran into this and found a solution that actually makes some sense at least for full volumes:
In some kernel release ... presumably around when this cropped up, the default device id naming changed from /dev/sdXX to /dev/xvdXXX - it seems both are still supported but that mdadm is looking for the new convention. Changing my device line cured all of my problems instantly. in mdadm.conf Instead of (or sda1, sda2 etc) DEVICE /dev/sdh[1-8] try (xvda1, sdva2 etc): DEVICE /dev/xvdh[1-8] you can see my discovery process here: http://ubuntuforums.org/showthread.php?t=1468064&page=5 take a look in /dev and you will probably see an xdvxxx entry that correspoibds to every sdxx entry ... not sure if it will help in the partition scenarios -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to the bug report. https://bugs.launchpad.net/bugs/27037 Title: mdadm cannot assemble array as cannot open drive with O_EXCL To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/27037/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
