I'm having issues to get the real client IP on a Kubernetes cluster v1.10.11

On my previous version Kubernetes 1.6.1 I had configured a nginx pod with a NodePort service and for that service I was using this old fashion annotation:

annotations:
    service.beta.kubernetes.io/external-traffic: OnlyLocal

And everything worked fine. This was the whole yaml service configuration:

apiVersion: v1
kind: Service
metadata:
  name: nginx-svc
  labels:
    app: nginx
  annotations:
    service.beta.kubernetes.io/external-traffic: OnlyLocal
spec:
  type: NodePort
  ports:
  - port: 80
    nodePort: 30080
    protocol: TCP
    name: http
  - port: 443
    nodePort: 30443
    protocol: TCP
    name: https
  selector:
    app: nginx

Now I'm using Kubernetes 1.10.11 over Ubuntu 16.04.4 LTS with Kernel 4.4.0-165-generic and docker 18.6.2.

I'm trying to use the new service.spec.externalTrafficPolicy: Local as described in this documentation and in this documentation however I'm not getting the real client IP.

I'm using same service and same pods configuration as I had in the past when using Kubernetes v1.6.1, just removing the old annotation and using service.spec.externalTrafficPolicy.

This is the new whole Service yaml file:

apiVersion: v1
kind: Service
metadata:
  name: nginx-svc
  labels:
    app: nginx
spec:
  type: NodePort
  externalTrafficPolicy: Local
  ports:
  - port: 80
    nodePort: 30080
    protocol: TCP
    name: http
  - port: 443
    nodePort: 30443
    protocol: TCP
    name: https
  selector:
    app: nginx

I'm asking here the question because I've followed official documentation and I have read all the similar issues described here in StackOverflow without success:

• How to preserve source IP from traffic arriving on a ClusterIP service with an external IP?
• Kubernetes ingress-nginx preserve source IP
• Preserve client source IP for Kubernetes ingress?
• How to read client IP addresses from HTTP requests behind Kubernetes services?

It's good to mention that I'm hosting my own cluster not using AWS, GCE, etc.

Any ideas what's going on? any suggestions to get this fixed?

Thanks !