+++ This bug was initially created as a clone of Bug #1093879 +++

As identified in https://bugzilla.redhat.com/show_bug.cgi?id=1087529 and probably elsewhere, Neutron in Icehouse notifies Nova about port status changes, and to do so it requires keystone credentials in neutron.conf.

After an upgrade for Havana to Icehouse, instances will fail to spawn because the required configuration is missing.

Our packages should do something to make this process more transparent.  Maybe modify the neutron-server startup to abort with an error if the appropriate configuration cannot be found?

--- Additional comment from Lars Kellogg-Stedman on 2014-05-05 16:56:19 EDT ---

We could handle this as we handled the database versioning check in the RHEL Havana packages, by running a check script prior to starting the service and exiting with an explanatory message if the appropriate configuration is not in place.

--- Additional comment from Alan Pevec on 2014-05-29 05:37:06 EDT ---

> Our packages should do something to make this process more transparent. 
> Maybe modify the neutron-server startup to abort with an error if the
> appropriate configuration cannot be found?

Default notify_nova_on_port_status_changes = True is wrong IMHO, and we should change it to False in dist.conf.
That way upgrades would work and be functionally no worse than the previous release while still allowing installers to change it to True along with all required parameters.
Startup script could issue a warning that configuration is sub-optional, but should not abort.