Demonstrating k8s¶

Local Kubernetes (docker)¶

Enable Kubernetes in Docker desktop.

• Deploy Busybox:

  # under lab/local-play
  kubectl apply -f busybox.yaml
  

• Deploy a webapp

  # under lab/local-play
  kubectl apply -f python-web-server.yaml
  kubectl port-forward service/python-webserver-service  8080
  

• Deploy k8s dashboard:

  kubectl apply -f https://raw.githubusercontent.com/kubernetes/dashboard/v2.7.0/aio/deploy/recommended.yaml
  

• Deploy postgresql

  kubectl apply -f postgresql.yaml
  # Then use psql
  kubectl exec -it [pod-name] --  psql -h localhost -U admin --password -p 5432 postgresdb
  

• Expose via a service

  kubectl expose deployment guestbook --type="NodePort" --port=3000
  kubectl get svc guestbook
  

• Scale the application

  kubectl scale --replicas=10 deployment guestbook
  kubectl rollout status deployment guestbook
  kubectl get pods
  

• Update the application version

  kubectl set image deployment/guestbook guestbook=ibmcom/guestbook:v2
  

• Rollout last version

  kubectl rollout undo deployment guestbook
  

• Remove the app

  kubectl delete deployment guestbook
  kubectl delete svc guestbook