Upgrading from Fedora 8 to Fedora 9 using Preupgrade

In the past, I've upgraded to the latest Fedora version by using the unsupported "yum upgrade". This is potentially dangerous, but it always worked for me. When I read in Red Hat Magazine that Fedora had a new tool to do in-place upgrades, I was excited to try it out.

I tried out Preupgrade on a few Fedora 8 virtual machines and everything went smoothly. Preupgrade had earned my confidence, so I proceeded to "yum -y update && yum -y install preupgrade && preupgrade" on my main Fedora 8 desktop. It downloaded all the RPMs and rebooted into the installer. It upgraded the system and said it was ready for the final reboot. So I rebooted the machine and was greeted by a blinking GRUB prompt. Somehow, GRUB had lost its configuration and could no longer boot my Fedora installation. Doh!

I've never really played around in the GRUB shell, so I never realized how powerful and versatile it is. All I had to do was the following (the {tab} indicates to use the Tab key for filename completion):

kernel (hd0,2)/vmlinuz{tab} root=/dev/sda5
initrd (hd0,2)/initrd{tab}
boot

The system came up and I then did the following to re-write GRUB into the MBR:

grub-install /dev/sda

And we have a working Fedora 9 installation!