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3rd chunk of `content/guides/ruby/deploy.md`
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   Your deployment should be listed as follows:

   ```shell
   NAME                       READY   UP-TO-DATE   AVAILABLE   AGE
   docker-ruby-on-rails-demo  1/1     1            1           15s
   ```

   This indicates all one of the pods you asked for in your YAML are up and running. Do the same check for your services.

   ```console
   $ kubectl get services
   ```

   You should get output like the following.

   ```shell
   NAME                        TYPE        CLUSTER-IP      EXTERNAL-IP   PORT(S)          AGE
   kubernetes                  ClusterIP   10.96.0.1       <none>        443/TCP          23h
   docker-ruby-on-rails-demo   NodePort    10.99.128.230   <none>        3000:30001/TCP   75s
   ```

   In addition to the default `kubernetes` service, you can see your `docker-ruby-on-rails-demo` service, accepting traffic on port 30001/TCP.

3. To create and migrate the database in a Ruby on Rails application running on Kubernetes, you need to follow these steps.

   **Get the Current Pods**:
   First, you need to identify the pods running in your Kubernetes cluster. Execute the following command to list the current pods in the `default` namespace:

   ```sh
   # Get the current pods in the cluster in the namespace default
   $ kubectl get pods
   ```

   This command will display a list of all pods in the `default` namespace. Look for the pod with the prefix `docker-ruby-on-rails-demo-`. Here is an example output:

   ```console
   NAME                                         READY   STATUS    RESTARTS      AGE
   docker-ruby-on-rails-demo-7cbddb5d6f-qh44l   1/1     Running   2 (22h ago)   9d
   ```

   **Execute the Migration Command**:
   Once you've identified the correct pod, use the `kubectl exec` command to run the database migration inside the pod.

   ```sh
   $ kubectl exec -it docker-ruby-on-rails-demo-7cbddb5d6f-qh44l -- rails db:migrate RAILS_ENV=development
   ```

   This command opens an interactive terminal session (`-it`) in the specified pod and runs the `rails db:migrate` command with the environment set to development (`RAILS_ENV=development`).

   By following these steps, you ensure that your database is properly migrated within the Ruby on Rails application running in your Kubernetes cluster. This process helps maintain the integrity and consistency of your application's data structure during deployment and updates.

4. Open the browser and go to [http://localhost:30001](http://localhost:30001), you should see the ruby on rails application working.

5. Run the following command to tear down your application.

   ```console
   $ kubectl delete -f docker-ruby-on-rails-kubernetes.yaml
   ```

## Summary

In this section, you learned how to use Docker Desktop to deploy your application to a fully-featured Kubernetes environment on your development machine.

Related information:

- [Kubernetes documentation](https://kubernetes.io/docs/home/)
- [Deploy on Kubernetes with Docker Desktop](/manuals/desktop/features/kubernetes.md)
- [Swarm mode overview](/manuals/engine/swarm/_index.md)
Title: Migrating the Database, Accessing the Application, and Tearing Down Deployment
Summary
This section explains how to migrate the database within the Ruby on Rails application running on Kubernetes using `kubectl exec`. It guides you through identifying the pod and executing the `rails db:migrate` command. It also explains how to access the application in your web browser, and how to remove the deployed application from the Kubernetes cluster using the `kubectl delete` command. Finally, it summarizes the deployment process using Docker Desktop and provides links to related documentation.