With Kubernetes, we can set the spec.LoadBalancerSourceRanges definition for the (Network) Load Balancer of the cluster.

This allows us to limit which client IP addresses can access the Load Balancer.

It would be useful if there is a way for CircleCI Server admins to be able to specify this too.

See https://kubernetes.io/docs/concepts/services-networking/service/

For Server 4.x in particular, it would help if this is configurable under the Helm values.yaml.

See https://circleci.com/docs/server/installation/installation-reference/#all-values-yaml-options