This topic describes how to use Enterprise Distributed Application Service (EDAS) to manage applications. For example, you can create, deploy, update, scale in, scale out, start, stop, reset, restart, and delete applications, and upgrade and downgrade runtime environments.

Create an application

You can develop an application based on the Apache Dubbo, Spring Cloud, or High-Speed Service Framework (HSF) framework and build the application into a WAR or JAR package. Then, you can deploy the application to an Elastic Compute Service (ECS) cluster in EDAS.

Deploy an application

After you create an application in EDAS, you can deploy the application. On the Basic Information page, click Deploy Application in the upper-right corner.

After you deploy the application, you can update the application. On the Basic Information page, click Deploy Application in the upper-right corner.
Notice When you update the application, you must select the same type of deployment package as that used when you deploy the application for the first time.

Roll back an application

If an exception is detected after the update of an application, you can roll back the application to the earlier version. On the Basic Information page, click Roll back Application in the upper-right corner.

If exceptions occur during the update of application instances, the deployment package is unavailable, or the health check fails, you can also roll back the application. On the Change Details page, click Stop Change in the upper-right corner.

Scale out an application

You can scale out an application by adding application instances to increase the computing capacity of the application. When existing application instances are overloaded, you can add application instances. On the Basic Information page, click Scale Out in the upper-right corner. For more information, see Add ECS instances to an application that is deployed in an ECS cluster.
Note If the total capacity of the instances to be added and the existing instances exceeds the upper limit that application resources can support, the scale-out request fails.

Scale in an application

You can scale in an application by removing application instances to decrease the computing capacity of the application. When the application is idle, go to the Instance Information tab and click Process Instances in Batch. In the Process Instances in Batch dialog box, select the instances that you want to remove, click Batch Stop, and then remove them.

Start or stop an application

You can stop an application as needed when it is running. After you stop this application, the billing and metering of related application instances are suspended. You can start or stop an application only when at least one application instance is available for this application. When you start or stop an application, all the instances available for this application are accordingly started or stopped. When more than one application instance is available, the startup or stop of an application instance affects only the status of this application instance. When only one application instance is available, the application starts or stops upon the startup or stop of this application instance.
Notice After an application that runs based on other services such as Server Load Balancer (SLB) or Virtual Private Cloud (VPC) is stopped, the services on which this application depends are still billed.
  • Start or stop an application

    On the Basic Information page, click Stop Application or Start Application in the upper-right corner to stop or start an application.

  • Start or stop an application instance

    On the Instance Information tab, click Enable or Stop in the Actions column to start or stop an application instance.

    On the Instance Information tab, click Process Instances in Batch. In the Process Instances in Batch dialog box, select multiple application instances and start or stop them.

Delete an application

On the Basic Information page, click Delete Application in the upper-right corner to delete an application.

Reset an application

On the Instance Information tab, click Reset in the Actions column to reset the runtime environment of an application instance. After the reset, the version of the runtime environment is not changed.

Restart an application

For a running application instance, click Restart in the Actions column on the Instance Information tab to stop and restart the instance.

Upgrade or downgrade the application runtime environment

After you deploy an application in an ECS cluster, you can upgrade or downgrade the runtime environment of this application during O&M to meet different functional requirements. For more information, see Upgrade or downgrade the runtime environment.