Deprecate support for 32-bit and PV AMI's for AWS Images

[Ben Howard]

The latest AWS regions and instance types do not support either PV or 32-bit instances. AWS and AWS luminaries are strongly suggesting user not use 32-bit images. For Ubuntu 15.10, 32-bit images have been deprecated. It is anticipated that Ubuntu 16.04 will be HVM only on AWS. As AWS capacity for PV and 32-bit instance types dwindles, users will 1) not be able to use new regions/zones and 2) experience "insufficient capacity" warnings.

Canonical's Cloud Image team is requesting that Juju Deprecate 32-bit and PV image support on AWS as soon as possible, as this will become a user-experience issue very quickly.

[Curtis Hovey (sinzui)]

We have several options in the case of streams:
A. stop including new i386 agents in ec2 (and maybe all CPCs)
B. And maybe remove all i386 agents from CPCs

We would continue to publish i386 agents on streams.canonical.com, tough I would prefer to stop making i386 agents all together.

I think the phase out of PV means that older jujus will stop working. My recent experiences retesting 1.18.x and 1.20.x have been poor because there is a high probability of failure when resources are not available orold juju gets an unsupported type.

[Cheryl Jennings (cherylj)]

Since we no longer will be making 32 bit agents for 2.0, can we consider this bug fixed?

[Robert C Jennings (rcj)]

This can be closed. I was thinking of where provider/ec2/instancetype.go defines types that specify "both" architectures or virtualization types of paravirtual. The issue is not important as you might have new regions and instances types that lack PV and 32-bit support but they also lack the instance types listed as supporting those. The only area where you'll find a minor issue is that Xenial is 64-bit AMI only so the user will not find 32-bit AMIs for that release even if the instance type supports it.

[Curtis Hovey (sinzui)]

We will stop placing 32-but agents in streams. This will also prevent users from selecting non-existent 32-bit images.

[Anastasia (anastasia-macmood)]

I am unclear: it looks like there is nothing to do on juju-core side.. Is it right?