User Story:

In IPv6-primary dual-stack, the target groups of API and Ingress NLBs have the following settings:

• IP type: IPv6
• Target type: instance(ID)

To register instances by instance ID for a IPv6 target group, the targets must have an assigned primary IPv6 address (see docs and announcement). For IPv4-primary dual-stack, the primary IPv6 is not required as target group IP type is IPv4.

Acceptance Criteria:

Description of criteria:

• A configurable and immutable field (e.g. AssignPrimaryIPv6: enabled/disabled) on MAPI AWS provider spec to define whether to enable primary IPv6 on the address.
• The field is only applicable in dual-stack infrastructure scenarios and should only be set to enabled/true if the containing subnet has IPv6 CIDRs (i.e. dual-stack subnets in this case).
• Alternatively, MAPI can automatically assign primary IPv6 based on whether the containing subnet has IPv6 CIDRs.

(optional) Out of Scope:

Detail about what is specifically not being delivered in the story

Engineering Details:

• [openshift/api] Define a new machine provider spec to allow setting Primary IPv6
• [cluster-api-provider-aws] Upstream implementation (as of now) is defined in the commit: 3310c7ff