Comment 2 for bug 607355

On Mon, Jul 19, 2010 at 05:35:37PM -0000, justinsb wrote:
> qemu: linux kernel too old to load a ram disk

This usually means that one or both of kernel and ramdisk has been
transferred incorrectly. You can go and see in
/var/lib/instances/<instance-id>/ and inspect the kernel and ramdisk

> * If I remove the -kernel, -initrd, and -append arguments I can get
> KVM to stop complaining about "kernel too old to load a ram disk"
>
> * If I leave the disk image as-is, it won't boot - it just hangs at the
> BIOS "Booting from Hard Disk" message (maybe nova is creating a
> corrupted disk image, c.f. "Input partition size not evenly divisible by
> sector size: 169 / 512" message?)

Make sure you've got parted installed. Nova does not currently check
properly if parted is installed, and does not handle the error if it
isn't.

> * If I swap the disk image to the original disk image created by
> vmbuilder, it hangs at "GRUB loading stage2"

> There's a whole bunch of questions here:
>
> Why are we using a kernel and ramdisk anyway - why not just rely on hardware virtualization?

Heritage from EC2/Eucalyptus. You provide a filesystem image, a kernel
and a ramdisk, and it gets stitched together to make up a virtual
machine.

> We presumably also wouldn't need to mess with the disk image...

Again, heritage from EC2/Eucalyptus. The idea was to look as much like
EC2 as possible. On EC2, the filesystem you provide is reachable on
/dev/sda2, and to make that happen with KVM, you need to fiddle with
disk images.

This definitely needs to be revisisted.

> How is that -no-kvm argument sneaking in there?

Can you attach the libvirt.xml from /var/lib/instances/<instance id>/ ?

> I'm guessing it's something I've misconfigured in the libvirt
> template?

That's my hypothesis, too. Did you run the sed command from the
NovaInstallFestInstructions page per chance?

> What is the correct way to build disk images, and where should the
> ramdisk & kernel come from?

That's a good question. Ḯ'll post info on how I built the one I used
tomorrow.

> Is there a way to boot a raw image without ramdisk/kernel?

Not at the moment. Patches to fix this are very welcome. You seem to
have identified that things that need to change. If not, don't hesitate
to ask.

--
Soren Hansen
Ubuntu Developer
http://www.ubuntu.com/