K8s – Add allowlist to existing Ingress

Once you have a working ingress in place, you may want to restrict access to it by IP.  Fortunately, K8s makes this pretty easy with a simple annotation.

1. Edit the ingress
2. Near the top should be the annotations metadata.annotations
3. Add the following annotation and update it with the desired IPs
   nginx.ingress.kubernetes.io/whitelist-source-range: ###.###.###.###/32,###.###.###.###/32
4. Save your changes
5. Test.