Comment 42 for bug 522197

Not really related to this bug , but to the boot hang problem people are experiencing; some of you might have a different issue, but here it goes:

When I installed Ubuntu I used a RAID 1 configuration (3 devices, md0 - boot, md1- / , md2 - swap).
At a later point I also created another RAID 1 (md3) on top of which I created a LVM.

Now the boot problem was due to the fact that I added a partition from the LVM to /etc/fstab but forgot to add the new raid (md3) to /etc/mdadm/mdadm.conf, so it wasn't up at boot.

I used a LiveCD to get into the system and add the missing entry to /etc/mdadm/mdadm.conf . Everything seems to be back to normal now. So it seems an invalid line in /etc/fstab (/dev/mapper/lvm-storage in my case) was the culprit. HTH