dns-integration api extension shouldn't be enabled by ovn_l3 plugin if there is no corresponding ML2 extension driver enabled

[Slawek Kaplonski]

In case when ovn_l3 service plugin is used it loads L3 API extensions from the list defined in neutron.common.ovn.extensions.ML2_SUPPORTED_API_EXTENSIONS_OVN_L3 list.
One of the extensions defined there is "dns-integration" extension which adds to the Port resource "dns_name" attribute.
But in fact this shouldn't be enabled if there is no enabled one of the ML2 extensions which provides dns integration.
The issue now is that if user will pass dns_name attribute to the neutron, it will be accepted as it is defined by dns-integration extension but this field will not be visible later as it's not processed properly if there is no extension driver enabled.

[Slawek Kaplonski (slaweq)]

Patch https://review.opendev.org/c/openstack/neutron/+/764831

[OpenStack Infra (hudson-openstack)]

This issue was fixed in the openstack/neutron 16.3.0 release.

[OpenStack Infra (hudson-openstack)]

This issue was fixed in the openstack/neutron 17.1.0 release.

[OpenStack Infra (hudson-openstack)]

This issue was fixed in the openstack/neutron 18.0.0.0rc1 release candidate.

[OpenStack Infra (hudson-openstack)]

This issue was fixed in the openstack/networking-ovn 7.4.1 release.

[Danny Webb (dannyswebb)]

So these patches unfortunately break DNS functionality in neutron and cause the dns-integration plugin to fail loading because it's not recognized as a supported plugin for OVN.

2021-06-23 08:56:42.180 7 INFO neutron.plugins.ml2.managers [req-8c74d86a-1f98-4ddd-b2a6-89bd6fa53e1e - - - - -] Initializing extension driver 'dns'
2021-06-23 08:56:42.180 7 INFO neutron.plugins.ml2.extensions.dns_integration [req-8c74d86a-1f98-4ddd-b2a6-89bd6fa53e1e - - - - -] DNSExtensionDriverML2 initialization complete
2021-06-23 08:56:42.208 7 INFO neutron.plugins.ml2.managers [req-8c74d86a-1f98-4ddd-b2a6-89bd6fa53e1e - - - - -] Got dns-integration extension from driver 'dns'
2021-06-23 08:56:42.237 7 INFO neutron.api.extensions [req-8c74d86a-1f98-4ddd-b2a6-89bd6fa53e1e - - - - -] Extension dns-integration not supported by any of loaded plugins
2021-06-23 08:56:42.238 7 INFO neutron.api.extensions [req-8c74d86a-1f98-4ddd-b2a6-89bd6fa53e1e - - - - -] Extension dns-domain-ports not supported by any of loaded plugins

We've managed to get it working again with the attached patches, but we're not 100% sure these are entirely correct as we're not that familiar with the neutron codebase.

[Danny Webb (dannyswebb)]

second patch

[Slawek Kaplonski (slaweq)]

Can You check if it is maybe fixed by https://review.opendev.org/c/openstack/neutron/+/795979 ?

[Slawek Kaplonski (slaweq)]

Ahh, and BTW. if not, please open new bug for that. It will be easier to track :)