Tech Blog Using technology to help your business

GRUB Error 21 Dual Boot Raid

I was installing Ubuntu to dual boot onto a newly added drive on my workstation that already has Windows XP. After the installation, GRUB gives me error 21. I looked through all the forums and help and tried everything from reinstalling GRUB to modifying menu.lst. Nothing worked. Then I figured out what the problem was. My system before adding the new drive had three drives; one with XP OS and two in a Raid 1 array for data. The issue was the Raid 1 array. With the new drive I added for Ubuntu, the computer had four drives. During installation, Ubuntu saw four drives and when installing GRUB, it pointed Ubuntu to boot on hd3,0. However, when GRUB tried to load, the BIOS was showing only three drives and hd3 was non-existent resulting in error 21.

Then I decided to move my SATA cables around so the location of the Ubuntu install does not change no matter if we saw the Raid 1 as one drive or two. So I kept XP on hd0, moved Ubuntu to hd1, and then having the Raid 1 drives to follow with hd2 and hd3. At this point, I reinstalled GRUB and tried to boot up again with the Raid 1 configured in the BIOS. Now I get GRUB error 17! What the heck is that? I found that if I got rid of Raid on the BIOS, error 17 goes away and GRUB comes up without a problem.

I got tired of trying to debug this and decided to just go all Ubuntu and just VM XP for the few things I still need to do on Windows.