Lame Virtualization messes up grub.

2008 Oct 28 at 23:12 » Tagged as :virtualization, python,

I tried to setup Xen virtualization on my media server and ended up with a messed up boot loader. There isn't a Fedora 9 xen installation guide, so I followed the instructions for Fedora 8. Part of those instructions include setting up the Xen kernel. So I did that and it updated my grub.conf file. Next I edited the config file to make the xen kernel is the new default kernel and after that I reluctantly rebooted.

After rebooting, I waited for the machine to come back up but it didn't, when I finaly walked over to it, the scree just had 'grub' on it and showed no inclination of changing. Yikes, I had forgotten to run grub-install. So it was time to boot up in rescue mode and try to update the boot sector. Unfortunately I kept running into the following error on grub-install

/dev/sdc2 does not have any corresponding BIOS drive.

I rebooted anyway and this time was rewarded with the grub console. That meant I could boot up the machine by manually entering the settings for kernerl, initrd etc. Once the machine is properly booted up, I reckoned I would be able to solve the problem easy.

What had once been /dev/sda had suddenly become /dev/sdc (I am so glad that UUIDs are now being used in the /etc/fstab instead of device names). This bit of information didn't get me very far either. Fortunately I came across a post from one Adrian 15 which explained what needs to be done; you need to edit devices.map on /boot/grub/

After making the change the file server does boot up normally but not with the xen kernel! So qemu is still the only choice available. It's not a bad choice actually.