ClusterIP - Kubernetes

ClusterIP --> The default service type, accessible only within the cluster. It's used for internal communication between services.
For example, communication between the front-end and back-end components of your application.

Create a 3 file

1. nginx-pod.yml
2. nginx-deployment.yml
3. nginx-svc.yml

apiVersion: v1
kind: Pod
metadata:
  name: nginx-pod
spec:
  containers:
  - image: nginx
    name: nginx-ctr

Execute the pod

kubectl apply -f nginx-pod.yml
kubectl get pods 

Get the pod full details

kubectl get pods -o wide

Create a deployment file

apiVersion: apps/v1
kind: Deployment
metadata:
  name: nginx-deployment
spec:
  replicas: 2
  selector:
    matchLabels:
      app: nginx
  template:
    metadata:
      labels:
        app: nginx
    spec:
      containers:
      - image: nginx
        name: nginx-ctr

Execute the deployment file

kubectl apply -f nginx-deployment.yml
kubectl get pods

Create a service file

apiVersion: v1
kind: Service
metadata:
  name: nginx-svc
spec:
  selector:
    app: nginx
  ports:
    - name: nginx-port
      protocol: TCP
      port: 32767
      targetPort: 80

Get the full information on pods

kubectl get all

Get the pod IP address

kubectl get pods -o wide (or)
kubectl get endpoints

POD → 1

POD → 2

Login to the container and change the Nginx file

kubectl -it exec nginx-deployment-7bb9945d7c-75nc5 -- /bin/sh

Get the services IP

kubectl get svc

Automatically load balancing selected

• Accessible only within the cluster → ClusterIP → Internal load balancer.

• Cluster IP service identifies pods using the selector → How pods are identified.

• Target port helps in identifying pod port → how port is identified.