I updated the kernel image via aptitude on one of my Debian Sarge servers but after a reboot it didn’t come up again. My first thought was that maybe there was something wrong with the boot loader and since I already wanted to switch from Lilo to Grub I took the opportunity and did just that.

Luckily the changeover is very easy, just follow those steps:

  1. aptitude install grub
  2. grub-install /dev/hda (Replace /dev/hda with the disk you want to install your bootloader on)
  3. update-grub to create the file menu.lst which holds all the information for booting with Grub
  4. Now we have to remove Lilo: aptitude purge lilo

That’s all folks! :)

If you want to automatically update the menu.lst whenever you install a new kernel, add the following to /etc/kernel-img.conf:
do_bootloader = no
do_initrd = Yes
postinst_hook = /sbin/update-grub
postrm_hook = /sbin/update-grub

…and now, reboot!