Jaunty booting problems with Grub2

So, I have a separate /boot partition. I installed the Ubuntu Karmic Alpha3 today. Foolishly enough, the first time, I didn’t install Grub. So, I boot into Jaunty and try to do the old grub-legacy “find /boot/grub/stage1″ , and it gives me the error 15: File not found, despite pointing it to the new Karmic partition. Ok, I say, I open Nautilus, go check out the /boot/grub folder on my Karmic / . Nada, single file which makes no sense to me. No wonder grub-legacy gives me an error 15.

I was thinking that Karmic would put it’s Grub files on it’s /boot like openSUSE even if I selected not to install it’s Grub. Stupid of me.

So, I go back to LiveCD, go through the install process all over again just to install the bootloader because I can’t find any grub from “which grub”, so a half-hour later, Karmic has finished installing over itself, and I reboot.

I want to see my Jaunty safe and sound first, so I press Esc (Thank God, that’s not changed) and I a confront totally different Grub. I think, “Must be a few aesthetic changes, that’s all”, select Jaunty’s kernel, Grub tells me I need to load the kernel first. Huh? How am I supposed to do that manually?

So, I reset the processor, boot into Karmic and Google Karmic Grub to find what’s different. Well, it’s Grub2 folks, that’s what’s different. So, I say, let’s just adjust Grub2’s menu.lst to boot Jaunty, after all, I have had some experience in such matters.

ls /boot/grub on Karmic gives me a whole list of files I’ve never seen in any Grub before. Woohoo, no menu.lst either. So, I think,let’s chainload grub-legacy from grub2. Google gives me all the results for chainloading GRUB2 from grub-legacy!

So, I read through some Ubuntu documentation about the new menu.lst(grub.cfg) littered with warnings about “NO MANUAL EDITING”, hit some paydirt which turns out to be just dirt, then think, After all Grub2 is a better bootloader,has to have done SOMETHING right to boot legacy OS. I reboot on a whim, see everything referring to Jaunty /boot or Jaunty / is correct, except one line which seems to allot Jaunty’s / UUID to Jaunty’s /boot. Delete the line, press Ctrl+X to boot (new Emacs style, not the old Vim-style “b for boot”) and I’m into Jaunty. Yay!

Now, just need to find out how to make that line disappear in grub.cfg, permanently(oh, ok, at least until Karmic releases)

Update:

The changes are made permanent by commenting out line 147 in /usr/lib/grub/grub-mkconfig_lib till this bug is fixed. Source

And this is the Ubuntu documentation I referred above: https://wiki.ubuntu.com/Grub2

Update2:

And no, till date, the change has never been permanent. Due to GRUB2 being in devel and changing to 1.96….1.97 etc with every GRUB update from the repos, the script I linked above is reverted, thus making me remove the –no-floppy line every time I dist-upgrade Karmic.