[ubuntu-cloud] deboostrapped lucid image from maverick fails on ec2 (with and without AKI/custom kernel)

[Scott Moser]

On Fri, 19 Nov 2010, Spike Spiegel wrote:

> Hi,
>
> > The maverick images (and natty and later) use pv-grub as their "kernel",
>
> just to clarify, you mean a pv_ops supported kernel, correct? the
> actual pv-grub kernel is on the host, not in the guests.

well... yes. the host loads pv-grub, and pv-grub loads the kernel, and
pv-grub reads the /boot/grub/menu.lst inside the image, and loads the
kernel that the menu.lst tells it to.

> > The 'lucid/server' url above contains information about 10.04 images.
> > 10.04 does not use pv-grub, as it was announced by amazon too late in the
> > 10.04 cycle.  That said, I've put some work into making that happen, and
> > have a ppa up at
> > https://launchpad.net/~smoser/+archive/lucid-kernel-upgrades
>
> feels like I'm confused and there's something that eludes me. Given
> that amazon has a pv-grub kernel in every zone and that lucid has a
> linux-ec2 kernel pkg recent enough that it supports pv_ops, why do I
> need that ppa? can't I just install that kernel and grub like I'd
> normally do for any other lucid box?

pv-grub and pv-ops are almost completely unrelated.  the linux-ec2 kernel
does not use pv-ops.  The linux-virtual kernels (used in maverick) do use
pv-ops.

> > You can do that manually as it appears you've done, or have
> > legacy-grub-ec2 manage the kernels for you (see that ppa)
>
> ok, thanks

The reason you'd want legacy-grub-ec2 rather than 'grub' is that
a.) grub will conflict with grub-pc (things, and if you're
running UEC host of 10.10 it can be used to load kernels).
b.) legacy-grub-ec2 has some ec2 specific things in it to that might make
things simpler (ie, it uses console=hvc0 by default and such).

> > In the second and third kernel logs there, it looks to me like the system
> > is booted fine.  I'm not sure what went wrong, but theres not a lot to go
> > on.
>
> that's the problem and frustration of working on EC2... if it boots
> and you can get in debugging is ok, but if you can't you're pretty
> much on your own :/
>
> > I promise that I'm not trying to be snooty.  I really do think that your
> > life would be easier if you just used the images that we've spent
> > resources creating.
>
> Believe me when I say I wish I could do that, I'd be happily punched
> in the stomach repeatedly than spending another day pulling my hair on
> this stuff, and yet here I am. I guess it'd be lovely if some of the
> resources spent creating those images were also spent in documenting
> how that was done.

Well, see https://wiki.ubuntu.com/UEC/Images/Publishing everything is
there, if not, ask.  We build these in fully revision controlled system
daily.