Take the 2-minute tour ×
Ask Ubuntu is a question and answer site for Ubuntu users and developers. It's 100% free, no registration required.

I just installed a new SSD in my system, and I'm having numerous problems trying to boot from it.

When I try to boot, the boot-loader-loader (Intel Matrix Storage Manager) skips right over it and tries to boot from the second drive. I installed Grub to the MBR on the second drive, pointing it to the boot files on the SSD. Unfortunately, the SSD is invisible to Grub. Running ls from the Grub rescue prompt shows only the second drive. However, if I boot from a LiveCD or flash drive, I can see and mount the SSD. I believe this is a BIOS problem, but I'm still curious.

How can my SSD show up in Ubuntu but not Grub? What is the difference between the way Grub finds filesystems and the way Ubuntu does?

share|improve this question
add comment

2 Answers 2

You are correct that this is a BIOS problem. GRUB (by default) uses BIOS interfaces to access drives, so GRUB will list all drives that the BIOS presents to it. Why your BIOS isn't able to access the drive I can't say, but you have a few options for working around your BIOS's limitation.

You can create a separate partition for /boot, putting it on a drive that the BIOS can read from. /boot contains all of the files that need to be read before the linux kernel is loaded and can use native drivers to access devices rather than relying on the BIOS. Or you can use GRUB's native drivers with grub-install --disk-module=foo /dev/sdX, where /dev/sdX is a drive the BIOS can boot from and foo is one of "ata", "ohci", "uhci",or "ahci" depending on how the drive is connected (PATA, different versions of USB 1.0 or SATA respectively). All but "ata" require grub 1.99.

share|improve this answer
    
I don't understand the second method for fixing the drive. Are you saying that I could boot from the SSD without creating a boot partition on the other drive? –  Evan Kroske Jan 25 '11 at 18:42
    
Yes, you would not need a /boot partition on the other drive. You would still need to have grub's boot sector and core.img installed to the mbr and post-mbr gap on the other drive though. I can't see much advantage in the second option but figured it was worth mentioning anyway. –  Jordan Uggla Jan 26 '11 at 19:33
    
Though unfortunately there isn't yet a good way to have --disk-module be preserved across upgrades of the grub-pc package. –  Colin Watson Apr 25 '11 at 20:35
add comment

I recently installed an SSD of my own and had my share of problems. The eventual solution was to use RAID as the SATA driver in the BIOS instead of AHCI or IDE. Setting up actual RAID disks wasn't necessary.

This way, my BIOS correctly recognized all my drives and I was able to boot to Ubuntu from the SSD. This worked on my Abit IP35 Pro motherboard. Might be worth a shot.

share|improve this answer
    
Unfortunately, my BIOS is already using the RAID driver. (It came that way.) –  Evan Kroske Jan 23 '11 at 20:00
add comment

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.