Day 32 Task: 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:

Create one Deployment file to deploy a sample todo-app on K8s using "Auto-healing" and "Auto-Scaling" feature

To deploy the sample ToDo app on Kubernetes using Deployment, follow these steps:

1. Create a YAML file named deployment.yml with the following content:

    apiVersion: apps/v1
    kind: Deployment
    metadata:
      name: todo-app
      labels:
        app: todo
    spec:
      replicas: 2
      selector:
        matchLabels:
          app: todo
      template:
        metadata:
          labels:
            app: todo
        spec:
          containers:
          - name: todo
            image: rishikeshops/todo-app
            ports:
            - containerPort: 3000
   

2. Apply the deployment to your k8s cluster by running:

    kubectl apply -f deployment.yml
   

3. Verify that the Deployment is created by running:

    kubectl get deployments
   

   You should see something like this:

   

   This shows that you have one Deployment named todo-app that has two replicas ready and up-to-date.

4. Verify that the Pods are running by running:

    kubectl get pods
   

   You should see something like this:

   

   This shows that you have two Pods named todo-app-<string> that are running and ready.

   Conclusion

   In this blog post, we learned how to launch a Kubernetes cluster with Deployment, a configuration that allows us to manage updates to Pods and ReplicaSets. We also deployed a sample ToDo app on Kubernetes using Deployment and enabled auto-healing and auto-scaling for it.

   I hope you enjoyed this blog post and learned something new. If you have any questions or feedback, please feel free to comment below.