Migrating to LILO from GRUB

If you replace GRUB with LILO in Debian (or derivatives), you're likely to encounter a situation where dpkg tries to run 'upgrade-grub' as part of installing a new kernel. Unfortunately, with grub missing, this will fail making kernel installation impossible. On the bright side, the answer is simple.

If you look at your /etc/kernel-img.conf file, it should look something like this:

# Kernel image management overrides
# See kernel-img.conf(5) for details
do_symlinks = yes
relative_links = yes
do_bootloader = no
do_bootfloppy = no
do_initrd = yes
link_in_boot = no
postinst_hook = update-grub
postrm_hook   = update-grub

Simply change it to remove the grub hooks and make it call your default bootloader instead (e.g. LILO):

# Kernel image management overrides
# See kernel-img.conf(5) for details
do_symlinks = yes
relative_links = yes
do_bootloader = yes
do_bootfloppy = no
do_initrd = yes
link_in_boot = no

After making the changes, dkpg should be able to install your kernel without any problems, calling LILO afterwards as prescribed.