k8s-home-lab/services-in-kubernetes/01/demos.md

1. Create a Deployment of nginx

kubectl create deployment my-nginx --image=nginx:latest --port=80

2. Expose the Deployment as a NodePort service

kubectl expose deployment my-nginx
--type=NodePort
--port=80
--target-port=80
--name=my-nginx-service

===============

backend-deployment.yaml

apiVersion: apps/v1 kind: Deployment metadata: name: backend spec: replicas: 1 selector: matchLabels: app: backend template: metadata: labels: app: backend spec: containers: - name: http-echo image: hashicorp/http-echo:0.2.3 args: - "-listen=:8080" - "-text=Hello from the Backend!" ports: - containerPort: 8080

backend-service.yaml

apiVersion: v1 kind: Service metadata: name: backend-service spec: type: ClusterIP # Default selector: app: backend ports: - port: 80 # Service port (used by internal clients) targetPort: 8080 # Container port in the backend Pod

frontend-deployment.yaml

---

- "-c"
while true; do
echo "=== Calling backend-service:80 ==="
curl -s backend-service:80
echo
sleep 5
done

apiVersion: apps/v1 kind: Deployment metadata: name: frontend spec: replicas: 1 selector: matchLabels: app: frontend template: metadata: labels: app: frontend spec: containers: - name: curl-loop image: curlimages/curl:7.86.0 command: ["/bin/sh"] args: