How to setup external remote cluster?

I followed the guide:

Its works correctly when the elasticsearch cluster is inside the same cluster k8s.

But I have issues to connect to an external cluster.

  • Can we expose the transport service 9300 behind a proxy http (nginx-ingress controller in this case) ? (I tried without success)

  • I saw that this transport service seems only used for discovery, after the "master" elasticsearch seems to establish direct connection to each node of the cluster (on port 9200 I suppose ?) . But if the cluster is external, we cannot expose directly the IP of each node, we need to expose these behind a service/load balancer. Is it correct, what is your suggestion ?

Thanks again