View Full Version : [ubuntu] Where to put grub ...

Bucky Ball
April 29th, 2012, 05:01 PM
Hi all,

I have Windows XP and 8.04 LTS (don't ask) dual-booting on sda. I want to install 12.04 LTS on sdb BUT I want the existing grub (8.04 LTS) to be running the show after install of 12.04 LTS.

So, I'm figuring I will need to install the 12.04 grub somewhere for it to boot. My questions:

Do I install the 12.04 grub onto the / partition on sdb (for instance sdb6=/)?
Will this allow me to boot with the original 8.04 grub, run 'sudo update-grub' in 8.04 and it will pick up the new 12.04 install and add it to the 8.04 grub menu?

Once I know that 12.04 is working okay I'm wanting to wipe 8.04 and have the 12.04 grub run things.

I have three Ubuntu installs on my laptop plus Win7 and the original Ubuntu install grub is still in charge. I didn't notice how I did that and don't remember changing anything re grub when I installed the other Ubuntus. Didn't take any notice of where grub was going! Guess what I'm looking for is how to dual-boot Ubuntu with and installs on different hard drives with the first install's grub in charge at the end of it all.

All advice welcome and tnx in advance ...

April 29th, 2012, 05:06 PM
I would put grub2 from 12.04 on /dev/sdb (the MBR of sdb). If your grub1 from 8.04 is on /dev/sda, that wouldn't overwrite it. Grub2 is not designed to work on a partition.

Another option is not to install it at all. In 11.10 they removed the option not to install grub2 so you had to install it somewhere. I haven't checked with 12.04 whether you can avoid installing grub2 or you need to install it somewhere.

Note that your 8.04 is probably using grub1 and I am not sure it can detect other OSs with update-grub as grub2 can. Maybe you will need to make a manual entry in /boot/grub/menu.lst. There is no need to chainload grub1 to grub2. You can boot 12.04 from grub1 also.