1. Proposed title of this feature request

CoreDNS Egress over multiple secondary networks

2. What is the nature and description of the request?

Forward DNS queries to upstream DNS servers not reachable from the MachineNetwork (the default infrastructure network) and reachable through secondary networks instead.

3. Why does the customer need this? (List the business requirements here)

Because of security reasons, some telco customers from our partners do not want to use MachineNetwork interface to reach external DNS servers assigned to secondary networks. This is for security reasons and they want to use secondary networks.
Partner is using in the meantime the following Support Exception based on using a custom DNS deploment and multus for a specific customer https://issues.redhat.com/browse/SUPPORTEX-27526 with a duration of 1 year.
Partner seeks for a general solution for multiple customers.

4. List any affected packages or components.
Openshift Core DNS