LinuxQuestions.org - Grub Chainloading /direct booting ( arising from Boot 100+ systems tutorial)

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Grub Chainloading /direct booting ( arising from Boot 100+ systems tutorial)

Hi.
Just read Saikee's highly impressive "How to boot 100+ systems via grub" tutorial. Two things arose on reading which have me asking questions.

1. Chainloading or direct booting. Why one and not the other ?

Several lines from that menu.lst file :

Code:

title          Asian Linux  @ hda33

root          (hd0,32)

chainloader    +1

                  

title          Ubuntu 6.04 Dapper (by direct boot) @ hda34

root          (hd0,33)

kernel        /boot/vmlinuz-2.6.15-8-386 root=/dev/hda34 ro quiet splash

initrd        /boot/initrd.img-2.6.15-8-386

Was there are reason why Ubuntu 6.04 was not chainloaded as well ? I assumed it could not be hence the "direct boot."

And number two question. During a new linux installation will you ask the boot loader ( that comes wiht that distro of linux) to be installed on the "root partition" as opposed to the MBR so it does not interfere with your "100+ grub menu.lst"
I take it you will have to edit your main menu.lst( which contains all the lisings to boot the 100+ os) manually. Adding separate lines for your new Linux.
Clarifying these two problems will definitely enhance my understanding of Grub and the way it operates.
I have a spare partition on a HD which already houses Ubuntu. I would like to install a new linux on this but do not want it to overwrite with my current grub startup menu /MBR which was installed by Ubuntu.
Essentially I would like to install the new linux and manually edit my original menu.lst adding the new linux details.

Cheers,
Uncle

Direct-booting v Chainloading:
The advantage of chainloading as Saikee suggests is that if a distro upgrades its kernel then you don't have to make any changes to the main menu.lst. All distros can be chainloaded, providing that they have their own grub installed in their root partition.

If you set everything up as Saikee suggests, then the only thing you need to edit the main menu.lst for is to change the name of this distro you are booting.

--Ian

Excellent. Everything now fits into place.
Getting into the nitty gritty of GRUB had been on my TODO list for a while. I've got a lot sorted over the last few days.
Much appreciated and thanks again,

Uncle.