Refresher: Kubernetes services

In the previous chapters, you have learned about Service objects, which can be used to expose Pods to load-balanced traffic, both internal as well as external. Internally, they are implemented as virtual IP addresses managed by kube-proxy at each of the Nodes. We are going to do a quick recap of different types of services:

• ClusterIP
• NodePort
• LoadBalancer

To make it easier to explain, we will assume that we have a Deployment running three replicas of Pods running the nginx container, which has the following YAML manifest:

apiVersion: apps/v1
kind: Deployment
metadata:
  name: nginx-deployment-example
spec:
  replicas: 3
  selector:
    matchLabels:
      environment: test
  template:
    metadata:
      labels:
        environment: test
  ...