--- description: Learn how to deploy containerized applications on a cluster, with Docker Universal Control Plane. keywords: ucp, deploy, application title: Deploy an app from the UI --- With Docker Universal Control Plane you can deploy applications from the UI using `docker-compose.yml` files. In this example, we're going to deploy an application that allows users to vote on whether they prefer cats or dogs. 😺 🐶 ## Deploy voting application In your browser, **log in** to UCP, and navigate to the **Stacks & Applications** page. There, click the **Deploy** button, to deploy a new application. ![](../../images/deploy-app-ui-1.png){: .with-border} The application we're going to deploy is composed of several services: * `vote`: The web application that presents the voting interface via port 5000 * `result`: A web application that displays the voting results via port 5001 * `visualizer`: A web application that shows a map of the deployment of the various services across the available nodes via port 8080 * `redis`: Collects raw voting data and stores it in a key/value queue * `db`: A PostgreSQL service which provides permanent storage on a host volume * `worker`: A background service that transfers votes from the queue to permanent storage Click **Deploy** and paste the following YAML into the **APPLICATION DEFINITION** field. ```none version: "3" services: redis: image: redis:alpine ports: - "6379" networks: - frontend deploy: replicas: 2 update_config: parallelism: 2 delay: 10s restart_policy: condition: on-failure db: image: postgres:9.4 volumes: - db-data:/var/lib/postgresql/data networks: - backend deploy: placement: constraints: [node.role == manager] vote: image: manomarks/examplevotingapp_vote ports: - 5000:80 networks: - frontend depends_on: - redis deploy: replicas: 6 update_config: parallelism: 2 restart_policy: condition: on-failure result: image: manomarks/examplevotingapp_result ports: - 5001:80 networks: - backend deploy: replicas: 2 update_config: parallelism: 2 delay: 10s restart_policy: condition: on-failure worker: image: manomarks/examplevotingapp_worker networks: - frontend - backend deploy: mode: replicated replicas: 2 labels: [APP=VOTING] restart_policy: condition: on-failure delay: 10s max_attempts: 3 window: 120s placement: constraints: [node.role == worker] visualizer: image: manomarks/visualizer ports: - "8080:8080" stop_grace_period: 1m30s volumes: - "/var/run/docker.sock:/var/run/docker.sock" networks: frontend: backend: volumes: db-data: ``` > When "Services" is selected, you can define services in this YAML file that have a `deploy:` key, which schedules the containers on certain nodes, defines their restart behavior, configures the number of replicas, and so on. These features are provided by the Compose V3 file format, which is currently in beta. You can [read the pre-release documentation for Compose V3 on Docker's preview URL for the upcoming Compose documentation](http://docker-docs-vnext-compose.netlify.com/compose/compose-file/#/deploy). Give the application a name (such as "VotingApp," used here), and click **Create**. Once UCP deploys the application, click on **VotingApp** or go to **Services** on the left navigation, to see the details of the services you have deployed across your nodes. Try clicking on the `visualizer` service, and scroll to the bottom of the detail page. You'll see a link to your UCP instance's URL that includes the published port of that service, which is 8080 in this case. ![Screenshot of deployed service](../../images/deployed_visualizer.png){: .with-border} Visiting that URL accesses the running instance of the `visualizer` service in your browser, which shows a map of how this application was deployed: ![Screenshot of visualizer](../../images/deployed_visualizer_detail.png){: .with-border} Here you can see some of the characteristics of the deployment specification from the Compose file in play. For example, the manager node is running the PostgreSQL container, as configured by setting `[node.role == manager]` as a constraint in the `deploy` key for the `db` service. ## Limitations There are some limitations when deploying docker-compose.yml applications from the UI. You can't reference any external files, so the following Docker Compose keywords are not supported: * build * dockerfile * env_file To overcome these limitations, you can [deploy your apps from the CLI](deploy-app-cli.md). Also, UCP doesn't store the compose file used to deploy the application. You can use your version control system to persist that file. ## Where to go next * [Deploy an app from the CLI](deploy-app-cli.md)