1. Proposed title of this feature request

Allow CoreDNS configuration to enable the loadbalance plugin

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

Our partner wants to configure the loadbalance plugin[1] in CoreDNS ConfigMap options[2]. [1] https://coredns.io/plugins/loadbalance/ [2] https://kubernetes.io/docs/tasks/administer-cluster/dns-custom-nameservers/#coredns-configmap-options However CoreDNS Configmap is under the control of the DNS operator in Openshift environment. Therefore the user cannot customize the CoreDNS configmap directly.

[1] https://coredns.io/plugins/loadbalance/ 

[2] https://kubernetes.io/docs/tasks/administer-cluster/dns-custom-nameservers/#coredns-configmap-options

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

Some partner workloads associated with a headless service.

Our customer expects IP addresses to be returned in the random order, so that the workload can be balanced to different pods. 

The k8s document[3] says,

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"Unlike normal Services, this resolves to the set of IPs of the pods selected by the Service. Clients are expected to consume the set or else use standard round-robin selection from the set."

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However, our customer cannot configure CoreDNS to make round-robin DNS loadbalancer available. The headless service always returns IP addresses of pods in a fixed order. So their workload is always focused to specific pod, even they have multiple pods. Our customer expects IP addresses to be returned in the random order, so that the workload can be balanced to different pods. [3]

[3] https://kubernetes.io/docs/concepts/services-networking/dns-pod-service/#a-aaaa-records

4. List any affected packages or components.

• CoreDNS
• DNS Operator