Enterprise Distributed Application Service:Manage an instance group in an ECS cluster in the EDAS console

Usage notes

• When an application is created in Enterprise Distributed Application Service (EDAS), EDAS creates a default group for the application. The default group cannot be deleted.

• If you do not need to deploy multiple versions of your application for traffic management and canary release purposes, the default group is sufficient for day-to-day use. In this case, you do not need to create any new instance groups.

• When you deploy an application, we recommend that you use the Java Virtual Machine (JVM), Tomcat, launch template, and Server Load Balancer (SLB) configurations of the instance group to which the application belongs.

Create an instance group

If you want to verify a new version of your application and you do not want to affect the traffic to your production environment, you can create an instance group for canary release of your application.

1. Log on to the EDAS console.

2. In the left-side navigation pane, choose Application Management > Applications. In the top navigation bar, select a region. In the upper part of the Applications page, select a microservices namespace from the Microservices Namespace drop-down list. Then, click the name of the application that you want to manage.

3. On the Basic Information page that appears, click the Instance Information tab, and then click Create Group in the upper-right corner.

4. In the Create Group dialog box, configure Group Name and Deployment Package Version, and click Create. A message that indicates The group is created. appears in the upper part of the page.

Add an instance to an instance group

After an instance group is created, you can add an instance to the group by using one of the following methods:

• Method 1: Scale out an application instance. For more information, see Scale out application instances in an ECS cluster.

• Method 2: Replace an instance group for an application instance. Procedure:

  1. On the Instance Information tab, click Change Group in the Actions column of the desired application instance.

  2. In the Change Group dialog box, configure Target Group and click OK.

     The following items describe the relationships among instance groups, applications, and application versions:

     • If no application version is deployed in the new group, the application version of the current instance, such as V1.0, is used as the default deployment version of the new group.

     • If an application version is deployed in the new group, such as V2.0, but the version is inconsistent with the application version V1.0 of the current instance, the two versions are displayed in the Change Group dialog box. In this case, select one of the following deployment policies based on your business requirements:

       • If you want to deploy the application version V2.0 of the new group to the current instance, set the Re-deployment parameter to Use Target Group Version for Re-deployment .

       • If you want to continue to use the application version V1.0 of the current instance, set the Re-deployment parameter to Change Group Without Re-deployment.

       Note

       If the deployment package version of the instance is different from the deployment package version of the group, a message appears.

View an instance group

1. Log on to the EDAS console.

2. In the left-side navigation pane, choose Application Management > Applications. In the top navigation bar, select a region. In the upper part of the Applications page, select a microservices namespace from the Microservices Namespace drop-down list. Then, click the name of the application that you want to manage.

3. On the application details page, click the Instance Information tab to view the group information and deployment package version of each group.

   • If an application is deployed in the group, the version of the latest deployed package is displayed next to the group name.

   • Instances are displayed based on the groups to which the instances belong.

Configure JVM and Tomcat parameters for an instance group

You can configure JVM and Tomcat parameters for an instance group. You can also configure JVM and Tomcat parameters for an application. For more information, see Configure applications deployed in ECS clusters.

1. On the application details page, click the Instance Information tab, and click Group Settings next to the desired group.

2. From the drop-down list, select JVM or Tomcat.

3. In the Group Settings dialog box, configure JVM or Tomcat parameters based on your business requirements and click Configure JVM Parameters or Configure Tomcat.

   For more information about the JVM and Tomcat parameters, see Configure applications deployed in ECS clusters.

Associate a launch template with an instance group

A launch template is used to create an ECS instance within a few steps. You can associate a launch template with an instance group to scale out ECS instances in the group in an efficient manner.

1. On the application details page, click the Instance Information tab, and click Group Settings next to the desired group.

2. From the drop-down list, select Instance Launch Template.

3. In the Group Settings dialog box, select Bind Launch Template, select a launch template and a version, and then click Modify.

Bind an SLB instance to an instance group

For more information about the scenarios and procedure of binding an SLB instance to an instance group, see Overview.

Delete an instance group

You can delete an instance group if the group does not contain instances and is no longer needed. Deleted groups cannot be recovered. Exercise caution when you delete an instance group.

1. On the application details page, click the Instance Information tab. On the tab that appears, find the group that you want to delete and click Delete Group on the right side.

2. In the Delete Group message, click Delete.

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