Open Stack

On Mon, Jul 07, 2014 at 03:29:31PM EDT, Scott Moser wrote:
> > I think it's also important to realize that the metadata service isn't
> > OpenStack invented, it's an AWS API. Which means I don't think we really
> 
> Thats incorrect.  The metadata service that lives at
>   http://169.254.169.254/
>    and
>   http://169.254.169.254/ec2
> is a mostly-aws-compatible metadata service.
> 
> The metadata service that lives at
>    http://169.254.169.254/openstack
> is 100% "Openstack Invented".

The URL structure and schema of data within may be 100% openstack invented,
but the idea of having a link local address that takes HTTP requests and
returns metadata was (to my knowledge) an Amazon EC2 idea from the
beginning.

There have been some good arguments and workarounds for the fact that
Amazon EC2 is not dual-stacked. My concern is that when Amazon finally
brings IPv6 to EC2, if we are trying to anticipate what they are going
to do on items like the metadata API, and we guess wrong, we're going to
have to make breaking changes. 

For now, I think we should document that only config drive for metadata
works in an IPv6 environment, and wait for Amazon to make changes to
their metadata API to enable IPv6 support, for those who wish for AWS
compatibility.

-- 
Sean M. Collins