On 09/13/2010 09:40 AM, Austin Godber wrote:
> So, were my instructions for creating HVM based images inaccurate? I
> had thought that HVM and the cluster compute type posed two separate
> issues. HVM works, but cluster compute images don't do to lack of
> support (for something) in the kernel.
I could be wrong but I believe the instructions you have are for
PVM-based images where you assign the image's AKI/ARI to a pv_grub
kernel/ramdisk. That pvm-grub kernel will then load your kernel from the
EBS root device using your EBS root device's /boot/grub/menu.lst.
The Cluster Compute works similarly, however, if you look at the Cent OS
HVM Cluster Compute reference image you'll see that it doesn't have an
AKI/ARI at all. I believe the HVM image instead loads Grub from the EBS
volume (rather then using the pv_grub AKI/ARI) and then uses stock Grub
to launch the kernel.
Also HVM kernels need high-performance pv drivers in order to use
ephemeral stores and attached EBS vols. Unfortunately when I applied
the patches, compiled, and tested the pv modules against a 2.6.32 kernel
I still couldn't get the resulting kernel to load (no console output
even!). I couldn't just use the 2.6.18 kernel from the reference image
(although I tried) since Ubuntu *has* to have a recent kernel otherwise
there are issues. So, I gave up on this for now until I have more time
to figure out what's needed to get a 2.6.32 kernel to launch on Cluster
Compute HVM machines.
In short, I think your instructions are for PVM and are identical to the
HVM process except that there's no AKI/ARI to assign and the kernel you
use with Cluster Compute HVM needs to be configured with the proper pv
modules from the Xen post.
Also, the EC2 dev docs state that user-provided/PVM kernel AMIs will not
work with the new Cluster Compute instance type:
"Cluster compute instances require the use of HVM-based, Amazon
EBS-backed AMIs. Paravirtual (PV) AMIs employed by Linux instances or
other EC2 instance types that use paravirtual machine (PVM)-based
virtualization are not supported. Cluster compute instances do not
require the use of Amazon Kernel Images (AKIs) or Amazon RAMdisk Images
(ARIs) that are part of PVM-based AMIs used with other EC2 instance types."
Received on Mon Sep 13 2010 - 11:56:22 EDT