<p>Once the application instances are created, a Kubernetes Deployment Controller continuously monitors those instances. If the Node hosting an instance goes down or is deleted, the Deployment controller replaces it. <b>This provides a self-healing mechanism to address machine failure or maintenance.</b></p>
<p>In a pre-orchestration world, installation scripts would often be used to start applications, but they did not allow recovery from machine failure. By both creating your application instances and keeping them running across Nodes, Kubernetes Deployments provide a fundamentally different approach to application management. </p>
</div>
<divclass="col-md-4">
<divclass="content__box content__box_lined">
<h3>Summary:</h3>
<ul>
<li>Deployments</li>
<li>Kubectl</li>
</ul>
</div>
<divclass="content__box content__box_fill">
<p><i>
A Deployment is responsible for creating and updating instances of your application
</i></p>
</div>
</div>
</div>
<br>
<divclass="row">
<divclass="col-md-8">
<h2style="color: #3771e3;">Deploying your first app on Kubernetes</h2>
<p>You can create and manage a Deployment by using the Kubernetes command line interface, <b>Kubectl</b>. Kubectl uses the Kubernetes API to interact with the cluster. In this module, you'll learn the most common Kubectl commands needed to create Deployments that run your applications on a Kubernetes cluster.</p>
<p>When you create a Deployment, you'll need to specify the container image for your application and the number of replicas that you want to run. You can change that information later by updating your Deployment; Modules <ahref="/docs/tutorials/kubernetes-basics/scale-intro/">5</a> and <ahref="/docs/tutorials/kubernetes-basics/update-intro/">6</a> of the bootcamp discuss how you can scale and update your Deployments.</p>
