2 grub install on 2 partitions

chip66 · 12-10-2011, 08:46 AM

I have Ubuntu 10.4 64 loaded on /dev/sda1 (flagged bootable) and
Ubuntu 10.4 32 on /dev/sda2 installed later.

It appears the grub on sda2 is taking precedence.

Can I unistall the grub on sda2 and expect the grub on sda1 to
take over?

PTrenholme · 12-10-2011, 09:17 AM

What difference would you expect to see?

If you just want to set you default boot location, ust edit your /etc/defaut/grub file to include

Code:

GRUB_DEFAULT="saved"
GRUB_SAVEDEFAULT=true
GRUB_TIMEOUT=10

and you will boot to the the last Ubuntu to which you booted after ten seconds (or when you press the enter key).

Remember to do a sudo grub_mkconfig -o /boot/grub.cfg after you change to defaults to create a new grub/cfg file.

See the Wiki for details.

If you really want to want each drive to be independent of each other, you can set the drive from which your system boots in your BIOS.

chip66 · 12-10-2011, 09:41 AM

Assuming the BIOS is not directing the boot loader...

The PC BIOS should be trying to boot the partition marked bootable. (All the partitions are on one drive.)

Larry Webb · 12-10-2011, 12:57 PM

Quote:

Originally Posted by chip66

Assuming the BIOS is not directing the boot loader...

The PC BIOS should be trying to boot the partition marked bootable. (All the partitions are on one drive.)

Bios will boot to the selected /dev (hard drive or mem stick).

The mbr with a boot loader installed on that /dev will select the partition to boot.

I do not believe grub cares where the boot flag is.

Larry Webb · 12-10-2011, 01:09 PM

Quote:

Originally Posted by chip66

Can I unistall the grub on sda2 and expect the grub on sda1 to
take over?

Another way is to boot your distro on sda1 and run command

sudo grub-install /dev/sda

If it does not pickup your distro on device sda2 run command

sudo update-grub

Here is a great tutorial on grub2