Azure Elasticsearch and NEST can't add index - azure

Question

In Azure I've created an Elasticsearch and Kibana cluster based on the (VM)template. In my unit test I use the Elasticsearch NEST nuget package to access my azure Electricsearch. A Ping just works fine
var node = new Uri("http://x:5601");
var settings = new ConnectionSettings(node);
var client = new ElasticClient(settings);
var response = client.Ping(new PingRequest());
Assert.IsTrue(response.IsValid);
But when I try to add an index I always get the error "Request must contain an kbn-xsrf header"
I have tried many things and tried to read as many examples but with no succes. Things I would like to know
Which nuget version should be used with the created VM. I figured out the azure enviroment runs ES 1 so I should use the nuget package
1.82
How should I authenticate in my code? I've found SetBasicAuthentication, still this doesn't seem to work beter
How to set or work with kbn-xsrf
Btw my index creating unit test looks like
var node = new Uri("http://x:5601");
var settings = new ConnectionSettings(node);
settings.SetBasicAuthentication("x", "x");
var client = new ElasticClient(settings);
var response = client.CreateIndex("hotelindex");
Assert.IsTrue(response.IsValid);

Answer 1

The Elastic ARM template deploys with either an internal load balancer or an external load balancer (which also deploys an internal load balancer for the following reason).
Kibana communicates with the cluster through the internal load balancer and looking at your Uri, it looks like you're sending the request to the Kibana endpoint. If you need to access the cluster through the REST API (directly or through a client), you also need to deploy an external load balancer as well.
Please note that for Kibana or external load balancer public IP addresses, the template does not configure SSL/TLS for them, so all communication is unencrypted. This is something that you will need to configure yourself.