Service exposition with ListenerClasses

While the listeners described here provide access to individual role groups, the Discovery ConfigMap is the recommended approach for general access to the OpenSearch cluster.

The operator deploys a Listener for each OpenSearch role group. The listener defaults to only being accessible from within the Kubernetes cluster, but this can be changed by setting .spec.nodes.roleGroups.{role-group-name}.config.listenerClass:

spec:
  nodes:
    roleGroups:
      cluster-manager:
        config:
          listenerClass: external-stable  (1)

1	Specify a ListenerClass, such as `external-stable`, `external-unstable`, or `cluster-internal` (the default setting is `cluster-internal`) at role group level. This can be set for all role groups individually.