Configure bootloaders
The bootloader permits you to boot on the OS you want and on the kernel you want. It makes the link between the BIOS and the kernel. I'll talk about the two most well known bootloaders on linux: LILO and GRUB.
5.1 LILO
First backup your working lilo.conf:
$ cp -p /etc/lilo.conf /root/lilo.txt
Now edit /etc/lilo.conf to make it bootable on the new kernel. Add this in the file:
image=/boot/vmlinuz-2.4.19 label=Linux-2.4.19 initrd=/boot/initrd-2.4.19.img read-only root=/dev/hda2
Do not change the "default=" line (above in lilo.conf) for the moment and do not delete lines corrosponding to current working kernel. The line "initrd=/boot/initrd-2.4.19.img" will be used only if you have made an initrd image (step 9). Now tell LILO to read lilo.conf:
$ lilo -v
Make sure the kernel have been loaded by looking at the output "Writing boot sector". Also tell LILO to treat "linux-2.4.19" as default boot kernel just for one time only with -R:
$ lilo -R linux-2.4.19
5.2 GRUB
backup the config file of GRUB:
$ cp /boot/grub/grub.conf /root/grub.txt
Edit grub.conf and make this changes:
title Linux 2.4.19 root (hd0,1) kernel /boot/vmlinuz-2.4.19 ro root=/dev/hda2 hdd=ide-scsi initrd /boot/initrd-2.4.19.img
(hd0,1) is the partition where GRUB is installed. root=/dev/hda2 is where the kernel image is located. Here again the line "initrd /boot/initrd-2.4.19.img" will be used only if you have made an initrd image (step 9). If your /boot has its own partition, remove /boot in the kernel path:
kernel /vmlinuz-2.4.19 ro root=/dev/hda2 hdd=ide-scsi
Higher in the configuration file, you can see a line "default=0". It means the first entry of grub.conf will be the default entry. If you want to set your new kernel as default, you have to put the above lines before your old kernel entry or if you wrote it at the end of the file, set "default=1". |