A Practical Guide to Kubernetes/

...

/

Accessing the Cluster: Understanding the Protocol

Accessing the Cluster: Understanding the Protocol

Learn how the different components in our cluster communicate with each other.

We'll cover the following...

Exploring the AWS ELB

We need a way to access the cluster. So far, we have seen that we can interact with the Kubernetes API. Every time we executed kubectl, it communicated with the cluster through the API server. That communication is established through AWS Elastic Load Balancer (ELB). Let’s take a quick look at it.

Press + to interact
aws elb describe-load-balancers

The output (limited to the relevant parts) is as follows:

Press + to interact
{
  "LoadBalancerDescriptions": [
    {
      ...
      "ListenerDescriptions": [
        {
          "Listener": {
            "InstancePort": 443, 
            "LoadBalancerPort": 443, 
            "Protocol": "TCP", 
            "InstanceProtocol": "TCP"
          }, 
          ...
      "Instances": [
        {
          "InstanceId": "i-01f5c2ca47168b248"
        }, 
        {
          "InstanceId": "i-0305e3b2d3da6e1ce"
        }, 
        {
          "InstanceId": "i-04291ef2432b462f2"
        }
      ], 
      "DNSName": "api-devops23-k8s-local-ivnbim-1190013982.us-east-2.elb.amazonaws.com", 
      ...
      "LoadBalancerName": "api-devops23-k8s-local-ivnbim", 
      ...

Judging from the Listener section, we can see ...