Comment 6 for bug 1341312

See my Bug report + workaround there a few minutes ago:
( need to close it ... )

https://bugs.launchpad.net/ubuntu/+bug/1367666

I definitly can confirm this problem, in a VMware workstation and also with real Hardware.

For the degraded MD device you need to boot a second time !!

As described in my bug report problem can also be replicated easly by installing Ubuntu 14.04 on only 1 disk of a RAID1 device

Workaound:

echo "sleep 2" > /etc/initramfs/scripts/local-premount/delay.sh ; chmod +x delay.sh ; update-initramfs -u

( can also be done from the initramfs prompt by mounting the root device + chroot /root )