We need a generic mechanism to support exposing the ONAP applications in IPv4 and IPv6 networks.
Thanks to Kubernetes 1.20, there is a very simple mechanism, which allows to set-up the service in two different networks (IPv4/IPv6):

• Only if these two DS networks are available
• With a single K8S service property (ip.FamilyPolicy).

The apporach will involve using K8S 1.20 and the updated IPv4/IPv6 DS approach in there, where a Service will get a modifier, called "ip.FamilyPolicy==PreferDualStack".
This will be then a generic change for all the services in ONAP,which has been with OOM team.

Backwards compatibility to support K8S 1.19 is as well in place - the Common service Helm chart will be equipped with a condition, that only if the run-time K8S environment is 1.20 (or newer), then these additional properties will be used in a service chart. In case of K8S 1.19 (or older) the properties won`t be really used.