Q:

Ubuntu Desktop 14 on PowerEdge doesn't boot on RAID

I have a Dell 1U PowerEdge 1950, and for some reason, we cannot install Ubuntu 14.04 64bit Desktop edition on it. I know what you're thinking... why are you installing desktop? I have asked the same question myself over and over again! The individual that will be using this server wants to use the GUI version of Virtual Box and as a result wants nothing but the Desktop version of Ubuntu installed. That issue aside, here is the weird part. I create a RAID 1 array between the two drives like normal and do the install like normal. Everything works great and the system installs successfully. Then upon reboot it drops me to the BusyBox v1.21.1 shell. I get dropped to a (initramfs) prompt. If I pull one of the RAID 1 drives and boot again, it will boot just fine. If I replace the drive and pull the other drive, it also boots just fine. This tells me it is something to do with RAID. ie, when the RAID array is degraded, it is just booting off a single drive as if no RAID was present. When the RAID is active though, it seems it cant boot.
Also, before you ask, we have confirmed this is not a hardware issue. I thought we had a RAID hardware issue and so I shipped the original server back and had it replaced with a completely different but identical server. I just tried to do the install again this morning on the new server and ran into the exact same issue.
Seems like this is a driver issue, but I have never experienced this before with Ubuntu.
Any thoughts?
Thanks!
Here is the shell I get dropped to with output:
Gave up waiting for root device. Common problems:
 - Boot args (cat /proc/cdmline)
   - Check rootdelay= (did the system wait long enough?)
   - Check root= (did the system wait for the right device?)
 - Missing modules (cat /proc/modules; ls /dev)
ALERT!  /dev/mapper/ubuntu--vg-root does not exist.  Dropping to a shell!

BusyBox v1.21.1 (Ubuntu 1:1.21.0-1ubuntu1) built-in (ash)
Enter 'help' for a list of builtin commands.

(initramfs)

A:

SOLVED
Boot into the system on one disk (ie degraded RAID array), and in /etc/default/grub, set:
GRUB_CMDLINE_LINUX="" 

to
GRUB_CMDLINE_LINUX="rootdelay=90"

then run
update-grub

Once that's done, reinstall the disk you removed and re-sync the RAID array using the good disk (Should normally do this by default). Then boot like normal. This is apparently a bug in Ubuntu 14.04. They set the rootdelay to low. This appears to effect other platforms as well.
Here is the bug: https://bugs.launchpad.net/ubuntu/+source/initramfs-tools/+bug/1326199
Cheers

