Save my current grub...

Prevention is better than cure…

I have an ubuntu 11.10 and suse 12.1 on my dell vostro 1500 laptop. The system uses the Grub loader installed by suse. Recently I did a customized distro at suse studio. Its a live DVD but I want to put it on the HD and test. At the same time I don’t want to change the bootloader - I want to use the current bootloader only.

How can I install my OS without touching the grub… Will it give me an option to install grub or skip it when I install the new OS

If it’s legacy Grub - like in openSUSE - you should install the Grub boot loader in the root partition of the OS you’re installing and nowhere else. It also means preventing openSUSE setup to write a generic bootcode to MBR, which it does by default. So you have to explicitely uncheck it in the boot loader options: http://www.unixversal.com/linux/opensuse/images/opensuse_vm_install43.jpg. However if it’s on another HD, you can install Grub in its MBR … but make sure you pick the MBR of the right disk. If you’re unsure, don’t install to MBR.

Well… I had windows 7 which is still there (in case I run into trouble with current systems) So I’m not sure where the grub has gone. However I’m able to edit the background images of the grub menu from my root partition. And its not grub 2. So as you said the grub should be in the root partition of my suse 12.1. Now I’ll uncheck the ‘write generic bootcode to MBR’ and do you think I’ll be OK??

This “feature” is tailored to Windows dualbooters. If you install openSUSE next to Windows, writing a generic bootcode to MBR is harmless, because a generic boot code is what Windows expects to find in MBR. If you install openSUSE next to another distro such as Ubuntu, Mint or the latest Debian and Fedora, writing a generic boot code to MBR is a bad idea (and therefore an absurd default) because it will overwrite Grub2 bootloader and replace something which is able to boot on its own with something that relies on an active partition. You can use findgrub to see where the different Grubs are installed on your computer (if you have more than one).

See the findgrub thread: looking-grub-windows-bootloader-all-partitions

The easiest way to install findgrub is to install the package updategrub (which includes findgrub) from my repo. It is available for openSUSE 11.3,11.4 and 12.1, Fedora 14, 15, 16 and mandriva 2010.1. Install as describe here: updategrub-opensuse-legacy-grub-not-update-grub.

One more thing: If you’re going to install several OSes or releases, always use “Create partition setup” and then “Expert mode”. With this option, you can select only the partition(s) you need without touching the others.

On 2011-12-16 11:36, melvinjose wrote:
> How can I install my OS without touching the grub… Will it give me an
> option to install grub or skip it when I install the new OS

When I install an extra openSUSE I tell it to install grub to the root or
/boot partition, and not to write generic code or anything to the MBR. The
new system is independent, and will in fact not boot: I have to manually
add an entry for it in the other grub that is installed on the mbr:

title Lilliput x64 – (hd2,0 /dev/sdb1 - chainload)
rootnoverify (hd2,0)
chainloader +1

Main grub boots, choose the other system, I get a second grub booting.


Cheers / Saludos,

Carlos E. R.
(from 11.4 x86_64 “Celadon” at Telcontar)