RFE NetworkMap functionality does not handle many port group to one NAD scenarios

The NetworkMap functionality is based around the idea that there is a 1:1 mapping between the source port group name and the target NetworkAttachmentDefinition which makes it unsuitable for migration scenarios where multiple source networks going to the same network in OpenShift.

The most common scenario for this many to one challenge is when multiple vSphere environments are being consolidated to fewer OpenShift clusters. When a naming standard such as SITE_DATACENTER_VLANID then it is likely to end up with a many to one mapping scenario.

Additionally vCenter on requires port groups to have unique names within the scope of a distributed switch.

One solution is to update the annotation lookup to support a list of source port group names such as infra.openshift-virtualization-migration/source-portgroup: '["pg1","pg2","pg3","pg4"]'.

For VLAN backed networks another option could be to lookup the NAD VLAN ID if the source port group annotation match finds no results.

Start with the NetworkMap functionality and its source-portgroup annotation lookup. Compare the many-to-one migration scenarios described, including list-based source port groups and VLAN ID fallback, and clarify which behavior is required. Done means an agreed approach supports multiple source port groups mapping to one NetworkAttachmentDefinition.