Open Stack

Hi all,

So I've been investigating bug #1383709, which has caused me to run into a
bad update pattern involving OS::Neutron::Port

http://docs.openstack.org/developer/heat/template_guide/openstack.html#OS::Neutron::Port

I'm not quite clear on the history, but for some reason, we have a
"replacement_policy" property, unlike all other resources, and it defaults
to replacing the resource every time you update, unless you pass "AUTO" to
the property.

I'm sure there's a good reason for this, but on the face of it, it seems to
be a very unsafe and inconvenient default when considering updates?

The problem (which may actually be the cause the bug #1383709) is the UUID
changes, so you don't only replace the port, you replace it and everything
that references it, which makes the Port resource a landmine of
HARestarter-esque proportions ;)

Can anyone (and in particular stevebaker who initally wrote the code) shed
any light on this?  Can we just flip the default to AUTO, as it seems to be
a more desirable default for nearly all users?

Thanks!

Steve