task_three.txt

Steps for deploying GKE app(scalable & highly available) with rolling update strategy.

1.Get the source code and Dockerfile from github...git clone

2.Then, build the container image with a tag that includes your GCP project ID
    docker build -t gcr.io${DEVSHELL_PROJECT_ID}hello-appv1 .
    
3.Authenticate to the registry ,and then push the image
    gcloud auth configure-docker

    docker push gcr.io${DEVSHELL_PROJECT_ID}hello-appv1
    
4.Create a Kubernetes Cluster in GKE with (autoscalling and regional cluster for high availability) enabled
	gcloud container clusters create lordson-cluster --zone us-central1-a --service-account 
  
5.Connect to the cluster .check the nods running.
	gcloud container clusters get credential lordson-cluster --zone us-central1-a

6.Create a deployment from image & scale no.of pods
	kubectl create deployment hello-world --image=gcr.io${DEVSHELL_PROJECT_ID}hello-appv1
    
7.Create a HorizontalPodAutoscaler resource for your Deployment
	kubectl autoscale deployment hello-app --cpu-percent=80 --min=1 --max=5

8.check the Kubernetes metrics in GKE with the kubectl top command
	kubectl top pods

	kubectl top nodes

9.Exposing the sample app to the internet
	kubectl expose deployment hello-world --type=LoadBalancer --port 80 --target-port 8080
  
10.get the Service details for your app .and check the EXTERNAL_IP address

	kubectl get service

11.Deploying a new version of the sample app & verify the same.
      Build and push a new hello-appv2 Docker image to registry.
		docker build -t gcr.io${DEVSHELL_PROJECT_ID}hello-appv2 .
      
        Apply a rolling update to the existing Deployment with an image update
		kubectl set image deployment hello-appv2 hello-app=hello-appv2