The kernel in Fedora Core 2 and higher is too big to fit on a floppy disk, so you’ll have to create a boot CD instead. Here are the steps.
1. Each installed kernel has a dedicated subdirectory for its modules in the /lib/modules directory. Get a listing of this directory. Here there are two installed kernels; versions 2.6.5-1.358custom and 2.6.8-1.521.
[root@bigboy tmp]# ls /lib/modules/ 2.6.5-1.358custom 2.6.8-1.521 [root@bigboy tmp]#
2. Select the desired kernel and use the mkbootdisk command to create a CD ISO image named /tmp/boot.iso of one of the kernels, in this case 2.6.8-1.521:
[root@bigboy tmp]# mkbootdisk --iso --device /tmp/boot.iso \ 2.6.8-1.521
3. Burn a CD using the image. This creates a boot CD with the specified kernel, named vmlinuz, and a scaled-down version of the grub.conf configuration file named isolinux.cfg, both located in the isolinux subdirectory of the CD. This example mounts the newly created CD-ROM and takes a look at the isolinux.cfg file to confirm that everything is okay.
[root@bigboy tmp]# mount /mnt/cdrom [root@bigboy tmp]# ls /mnt/cdrom/isolinux/ boot.cat boot.msg initrd.img isolinux.bin isolinux.cfg TRANS.TBL vmlinuz [root@bigboy tmp]# cat /mnt/cdrom/isolinux/isolinux.cfg default linux prompt 1 display boot.msg timeout 100 label linux kernel vmlinuz append initrd=initrd.img ro root=/dev/hda2 [root@bigboy tmp]#
When you reboot your system with the CD, the boot process automatically attempts to access your files in the /root partition and boot normally. The only difference being that the kernel used is on the CD.