Comment 1 for bug 367782

I have been searching Ubuntu Forums and found

http://ubuntuforums.org/archive/index.php/t-1021719.html

It is the same issue. It is interesting that the problem only manifests itself if there is no CD-ROM drive installed. This is the case with the server machine I am using.

The last post in this forum page is as follows:

"
Okay, I think you might have a "race" condition. Edit this file:

/usr/share/initramfs-tools/init # to stop a race condition

187 maybe_break mount
188 sleep 10
189 log_begin_msg "Mounting root file system..."

sudo /usr/sbin/update-initramfs -uk all # run to rebuild the image

Make sure you get to the "mount" line. Lines numbers are likely different for your setup than mine.

If this works you might try lower number than 10 to get the least delay needed. If it doesn't some other delay could be added, here and there.

Good luck!
"

I have tried this fix but initially it did not work. I changed the the sleep value from 10 to 50 and this worked. I tried 20, it also worked. I tried 11, it failed. I tried 15, it works and I stopped here. Although booting up takes a little longer I can live with this as the machine is very rarely rebooted.

Hope this helps you iron out this bug.