[Ubuntu] grub2

[RabbieBurns]

Been testing grub2 in chainloader mode the last week or so.. Just recently made it the default boot loader on my Vaio TZ.

https://wiki.ubuntu.com/KernelTeam/Grub2Testing

Took me a while to figure out how to get my grub splash and colours sorted, they moved things from the menu.lst into grub.cfg which is auto generated automatically, and you need to edit a couple of different files.

[dhicks]

Been testing grub2 in chainloader mode the last week or so.

What does it do that plain grub doesn't? Does it support ext2 file systems with more than 128 bytes per inode, by any chance? Took me a while to figure out that problem - formatted an ext2 partition with the latest version of System Rescue CD, then couldn't figure out why grub couldn't read menu.lst off it - turns out mke2fs defaults to 256 bytes per inode now, which the version of grub that ships with System Rescue CD can't handle. Easily fixed by formatting with e.g. "mke2fs -i128 /dev/hda2", but fiddly to remember.

--
David Hicks

[RabbieBurns]

Ive not really got a clue what the new grub does over the old one..

However, now that Im running grub2 I think Ive put myself into a bit of a dilemma with regards to upgrading to Win7 on my laptop.

I have like this

sda1: Sony Vista Recovery Partition
sda2: Win XP
sda3: Ubuntu

Now, if I replace the XP partition with 7, Im assuming I will lose my grub bootloader?

Normally I would just use the ubuntu cd and do something to copy it across.. but with me using grub2, its a different version to whats on the ubuntu cd, and uses different files etc, ie its no longer menu.lst etc.

Any suggestions what I might be able to do?

[powdarrmonkey]

Amongst other things it's modularised and much more portable.

From the GNU blurb:

GRUB 2 targets at the following goals:

• Scripting support, such as conditionals, loops, variables and functions.
• Graphical interface.
• Dynamic loading of modules in order to extend itself at the run time rather than at the build time.
• Portability for various architectures.
• Internationalization. This includes support for non-ASCII character code, message catalogs like gettext, fonts, graphics console, and so on.
• Real memory management, to make GNU GRUB more extensible.
• Modular, hierarchical, object-oriented framework for file systems, files, devices, drives, terminals, commands, partition tables and OS loaders.
• Cross-platform installation which allows for installing GRUB from a different architecture.
• Rescue mode saves unbootable cases. Stage 1.5 was eliminated.
• Fix design mistakes in GRUB Legacy, which could not be solved for backward-compatibility, such as the way of numbering partitions.

Good to know it's gone well for you, IIRC it's one of our release goals for squeeze so that's reassuring

[powdarrmonkey]

Now, if I replace the XP partition with 7, Im assuming I will lose my grub bootloader?

Normally I would just use the ubuntu cd and do something to copy it across.. but with me using grub2, its a different version to whats on the ubuntu cd, and uses different files etc, ie its no longer menu.lst etc.

Any suggestions what I might be able to do?

Yes, you will.

I've never done this with grub2, but on other occasions:
- do your windows stuff and lose the bootloader
- boot into a rescue cd
- mount your Ubuntu root partition and chroot to it
- assuming all other requirements are present, reinstall the grub2 package (you did it from the package, right?)

[RabbieBurns]

right, sounds fairly straight forward (famous last words)

Whats the command to chroot again, Ive not had to do that for a while..

Yeh, it was just installed through apt, so hopefully should just work.. Will give it a try tomorrow or monday.

Thanks

[powdarrmonkey]

Whats the command to chroot again, Ive not had to do that for a while..

That would be chroot(8)

[RabbieBurns]

Ive only got an ubuntu 8.10 cd, but running 9.40.. Do I need to get hold of a 9.40 CD to do the chroot and grub2 install, or will it work with the 8.10 cd?

[powdarrmonkey]

It should be fine, chroot just straps you into the target installation as if you'd booted it. It doesn't do any automatic mounting, init scripts etc though.

[RabbieBurns]

OK, got booted off the CD fine, mounted and chrooted to the existing ubuntu partition, did an

apt-get --reinstall install grub2

and rebooted but it didnt launch grub. I feel Ive forgotton a step, to install grub onto /dev/sda2 ?

[powdarrmonkey]

Try dpkg-reconfigure grub2

[RabbieBurns]

it was

grub-install /dev/sda2

that I was missing..

But its now broke the windows boot

Will need to read up now on what to put in the grub config to get it to boot win7 instead of xp

[RabbieBurns]

hmm cant get it booting to anything else now heh

It now goes back to the grub menu when im choosing the windows options....

[SYNACK]

Windows 7 upgrade and fixing Grub afterward. : You Will Get A Virus

[RabbieBurns]

cheers, but the problem is, ive got grub back workgin again after the windows install, but now I cant get to windows.