🚀Day 32: Launching your Kubernetes Cluster with Deployment😃

What is Deployment in k8s

A Deployment provides a configuration for updates for Pods and ReplicaSets.

You describe a desired state in a Deployment, and the Deployment Controller changes the actual state to the desired state at a controlled rate. You can define Deployments to create new replicas for scaling, or to remove existing Deployments and adopt all their resources with new Deployments.

Task-1:

Create one Deployment file to deploy a sample todo-app on K8s using “Auto-healing” feature

• Make sure you have a Kubernetes cluster set up, either locally or on a cloud provider.

• Create a file named “deployment.yml” with the following contents:

apiVersion: apps/v1
kind: Deployment
metadata:
  name: todo-app
  labels:
    app: todo
spec:
  replicas: 3
  selector:
    matchLabels:
      app: todo
  template:
    metadata:
      labels:
        app: todo
    spec:
      containers:
      - name: todo
        image: rishikeshops/todo-app
        ports:
        - containerPort: 3000

• Run the command “kubectl apply -f deployment.yml” to apply the YAML file to your Kubernetes cluster. This will create the Deployment.

• Verify that the Deployment was created successfully by running the command “kubectl get deployment todo-app” . This should show you the current number of replicas.

• Test the auto-healing feature by intentionally crashing one of the containers in the Deployment. You can do this by running the command “kubectl delete pod <podname>”, where <podname> is the name of one of the running pods. Kubernetes should automatically spin up a new pod to replace the one that was deleted.

• Now if you check the pods a one pod is getting terminated while a new pod is up and running to make sure there is always replicas=3.

Congratulations, you’ve now deployed a todo-app with auto-healing feature.

Thank you for reading. I hope you now have a better understanding of Kubernetes.

Happy Learning :)