Comment 5 for bug 1788487

@Mark,

We did not intend to break your use case on 16.04.
Upstream has required strict identification of the platform for some time.
(bug 1669875 was filed ~ 18 months ago).

We do intend to support "explicit" datasource configuration via
setting datasource_list to have 1 entry (or 2 entries if the second is
'None'). I'll look to fix that for OpenStack here. bug 1787459 currently
blocks doing that correctly, but we'll get that fixed as well.

> As for identifying OpenStack platforms: I think this is an impossible
> task with the large variety of distros out there, many of them built on
> older OpenStack releases. If platform identification were to be made a
> requirement in the next OpenStack release, it will take years before
> every distro and deployment out there is updated to conform to this (if
> ever).

Older OpenStack platforms will simply need some image customization
to get Ubuntu releases until they are able to identify themselves. Lets
clarify that 'older' here means older than Grizzly which went end of
life 2014-03-29 / over 4 years ago (at least for libvirt platforms).
I realize that other platforms support differ, but the point is that
this is not by any means a new feature of OpenStack.

> The next best thing I can come up with is adding a non-strict
> mode like in the EC2 datasource (so that metadata is always probed), or
> always probing the metadata service and removing OpenStack from the
> default list of datasources.

Do you think it is sufficient to just allow explicit customization of
the datasource? Ie:
 echo "datasource_list: [OpenStack, None]" > /etc/cloud/cloud.cfg.d/99.cfg

?