[Starcluster] Custom Kernels in AMIs

[Austin Godber]

Hi Justin,
     If you follow the process I described, you will end up with an AMI 
that uses the pv_grub kernel, but it still shows up as paravirtualized.  
I thought I saw someone mention that the upcoming tools would actually 
set the virtualization platform, I think that was in the AWS forums, but 
I can't find it at the moment.

     I have not heard of anyone using the new instance type yet, nor 
have I tried.  If you would like, you can send me your AWS User ID and I 
will share my AMIs with you.  Oh, I have just realized that I made 32bit 
images so they wouldn't even launch as that instance type.  I should 
have thought of that earlier.  So, for HPC purposes, those instructions 
need modification, they need to switch the AMI launched to a 64 bit and 
then switch to the 64bit pv_grub kernel.  They paths to the kernel and 
initrd in the grub conf will need changing too.

     If I get a chance I will build a 64bit AMI but it will be a couple 
days before I can get to it.  Then we can actually try and launch and 
AMI of that instance type.

Austin


On 07/20/2010 01:21 AM, Justin Riley wrote:
> Hi Austin,
>
> > I have documented the process for converting an Ubuntu 10.04 AMI to
> > using the pv_grub kernel.
>
> This looks really good, thanks for writing this up.
>
> > I think, once they update the tools again it will be
> > possible to mark the AMI as 'hvm' rather than 'paravirtual' or I have
> > overlooked that setting.
>
> So for now it appears that Amazon detects whether you're using 
> paravirtual AMIs or not simply by the AKI/ARI you use (ie pv_grub 
> kernels). Whether or not they'll add a 'paravirtual'/'hvm' flag or not 
> is a good question.
>
> Given that the reference AMI that Amazon has released looks no 
> different than any other EBS/AMI only with no AKI/ARI specified I 
> would imagine there would be some sort of flag during image creation 
> to mark an AMI as HVM. Amazon certainly hasn't exposed anything like 
> that and only advertises extending their CentOS reference HVM/EBS AMI.
>
> Have you heard of anyone that has actually used something other than 
> Amazon's reference CentOS AMI with the new cluster instance type?
>
> ~Justin
>
> On 07/19/2010 02:15 PM, Austin Godber wrote:
>> Hello Guys,
>>       I have documented the process for converting an Ubuntu 10.04 
>> AMI to
>> using the pv_grub kernel.  It is relatively painless, all you have to do
>> is write the appropriate grub config file and then rebundle with the
>> pv_grub kernel.  I think, once they update the tools again it will be
>> possible to mark the AMI as 'hvm' rather than 'paravirtual' or I have
>> overlooked that setting.  Regardless, I think that would just be a flag
>> and the real indication as to whether or not you are running in hvm mode
>> is whether it boots off of the pv_grub kernel.
>>
>> Here it is:
>> http://blog.crunch.io/user-managed-kernel-amis-from-existing-ubuntu
>>
>> Austin Godber
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>