Dual-booting DSL/Ubuntu

SnoringFrog · 02-04-2009, 06:31 AM

Quote:

Originally Posted by blackhole54

I've not taken the time to figure out what this is about, but take a look at this page and see if it relevant. I'm not sure why it would matter, but at first glance it sounds like maybe an old GRUB version from DSL can't boot a new kernel.

If that's the case, where do I go about getting an updated GRUB version to install?

blackhole54 · 02-05-2009, 02:25 AM

Can you boot the machine into DSL? If so, do that and run the command

Code:

grub --version

to see what version you currently have. I think I know the answer, but let's make sure. Also, let me know what version of DSL you are running.

Do you have a Ubuntu live CD you can boot from? If so, I am thinking that might be as good a place as any to get the updated GRUB. I should let you know that this is an area I am not real confident in. (Anybody else reading this thread, if you are familiar with this, take that as your cue to jump in.) So if we proceed, I will try to have you back up what I think is needed to restore to where you are now (should things go bad), but you will have to decide whether you want to move forward.

SnoringFrog · 02-24-2009, 06:28 AM

For my grub version I got 0.91.

And yes, I've got an Ubuntu Live CD I can use.

blackhole54 · 02-27-2009, 04:57 AM

Quote:

Originally Posted by blackhole54

I should let you know that this is an area I am not real confident in. (Anybody else reading this thread, if you are familiar with this, take that as your cue to jump in.) So if we proceed, I will try to have you back up what I think is needed to restore to where you are now (should things go bad), but you will have to decide whether you want to move forward.

I am quoting myself here just to emphasize I could have this wrong. Feel free to check other sources to verify what I say, or if you feel it too risky, not proceed at all.

The first thing is to boot from the Ubuntu live CD. You will be altering the MBR, so I would suggest you make a backup of your existing MBR. I would suggest writing it to a key drive or floppy, but you can write it to somewhere on the hard drive if you prefer. After you have mounted whatever you are going to write to:

Code:

sudo dd if=/dev/sda bs=512 count=1 > <path>/old_mbr.img

Mount your DSL partition:

Code:

sudo mkdir /mnt/sda2
mount /dev/sda2 /mnt/sda2

Make sure the layout is what I think.

Code:

ls /mnt/sda2/boot/grub

You should see DSL's menu.lst file along with several files the have "stage" in their name, such as stage1, e2fs_stage1_5, stage2, etc. I believe these "stage files" are what need to get updated with the files from a new version of GRUB. To copy the new files over but retain the old files as backups:

Code:

cp -p --backup=numbered /usr/lib/grub/i386-pc/*stage* /mnt/sda2/boot/grub

I am basing the source directory on Ubuntu 8.04, but it is probably the same on your version.

You then need to install the new MBR:

Code:

sudo grub
grub> root (hd0,1)
grub> setup (hd0)
grub> quit

Cross your fingers, reboot and see if it works.