I have SUSE 10 and XP installed on a dual boot system. This has had various distros installed in recent months, my favourite is SUSE but I still have some affection for Ubuntu. Mandriva is still 'installed' on one partition (SDA5) but that didnt work (couldnt detect my SATA HD) so it is just taking up space and is NOT in the grub menu.lst.

I would like to overwrite the Mandriva instal with Ubuntu but KEEP SUSE and KEEP the SUSE Grub menu. If I install Ubuntu (5.04) will it give me the option writing to SDA5 and will it automatically add itself to the existing Grub menu or is the latter best done manually?

I do not want to just 'try it and see what happens' as I dare not take any risks with this as certain other members of the family have totally lost patience with my constant tinkering. So it is essential that SUSE, XP and the existing Grub menu remain untouched.

As long as you don't mess with the existing SuSE and XP partitions, you should be able to easily install another distro into any free partitions. If you do not have any unused partitions (or unallocated space) on your drive into which you could install another distro, then you will need to resize or repartition.

As for GRUB, if you have any concerns, the best thing to do is a.) make a backup copy (or two if you really want to play it safe) and b.) manually edit the GBUB yourself to add the new distro as a boot option. As a general rule, anytime you give an automatic process control, it's possible that its idea of the right action might not be the same as yours. If you have any concerns about what the outcome might be, do it manually. Good luck with it

As J.W. said,

but aren't there distros that do not allow to skip the automatic bootloader installation?

I remember having some headache with Suse and the above issue, though it was some time ago.

It is very good advice to backup the Grub menu.lst, I have learned the hard way that even 'minor' errors in this file can cause big problems.

Following advice from another SUSE/Ubuntu user this is what I did.

Installed Ubuntu on spare partition and let it automatically detect my existing SUSE and XP inmstallations.

Let Ubuntu write a new Grub file to the MBR, reboot and finish the install.

Then reboot and log into SUSE and go into YAST > System > Boot Loader, and select "Other", and let SUSE Propose New Configuration. Confirmed the proposed scheme and SUSE reinstalled it's own grub, with all distros included in menu.lst.

It worked so well that I could hardly believe it.

Excellent - congrats on solving the problem Vulpus and thanks for posting back with the update

Thank you for the solution I had a similar problem configing GRUB to load CentOS after install. I'll try your method of allowing Cent to install GRUB then reconfiging GRUB with Suse. I have Suse and Xp running on my main drives and Cent installed but unaccessable on a rack drive. When I installed Cent I told it to not load a bootloader and since then have been unable to access it. My hopes are to use my rack drive to swap out harddrives loaded with diffrent OS while keeping the dualboot OS on my main non-removable harddrives.
Thanks again for the solution you have no idea what I've been through these last couple days rying to figure this out