Had a similar problem, got fixed by using UUID in grub & fstab, no extra options like "mount=device=/dev/sda2,device=/dev/sdb2" required.
Used btrfs as / for Ubuntu server 11.04. Example: #btrfs device add /dev/sdb1 / #btrfs filesystem balance #btrfs filesystem show Check if UUID is the same as in /etc/fstab & grub2. #reboot works! -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/774502 Title: Ubuntu 11.04 initrd fails to boot mult-volume BTRFS filesystem -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs