Basic Operations on Applications

Deleting an Application

Delete an application that you do not need to use any longer. Applications cannot be restored after being deletion. Exercise caution when you perform this operation.

1. Log in to the CCE console. In the navigation pane, choose Application Management.
2. Click More > Delete for the application to be deleted, and follow the prompts to delete the cluster.
3. Click OK.

Upgrading an Application

CCE enables you to quickly upgrade applications by replacing images or image versions without interrupting services.

To replace an image or image version, you need to upload the image to the image repository in advance. For more information, see Uploading a Private Image from the Internet and Uploading a Private Image from an Intranet.

1. Log in to the CCE console. In the navigation pane, choose Application Management. On the page that is displayed, click the application to be upgraded. On the Application Details page, click the Upgrading tab.
2. Upgrade the application based on service requirements.
   • To replace the image, click Change Image and select a new image.
   • To replace the image version, select a version from the Image Version drop-down list.
   • To change the container name, click next to Container Name and enter a new name.
   • To let containers run in privileged mode, set Privileged Pod to true.

     Privileged containers have super permissions that are not available to regular containers. For example, privileged containers can use network devices on the host machine and modify the host's kernel parameters.

   • For details on how to configure advanced settings, see Table1 Advanced settings.

     Table 1 Advanced settings

     Parameter	Description
     Lifecycle	Commands that are executed in each lifecycle phase of an application. Startup Command: executed when the application is started. For details, see Setting Container Startup Command. Post-Start Processing: executed after the application is successfully run. For more information, see Setting Container Lifecycle. Pre-Stop Processing: executed to delete logs or temporary files before the application ends. For more information, see Setting Container Lifecycle.
     Health Check	Set the health check function that checks whether containers and services are running properly. Two types of probes are set: application liveness probe and application service probe. For more information, see Checking the Health of Containers. Application Liveness Probe: Restarts the application when detecting that the application instance is unhealthy. Application Service Probe: Sets the application to the unready state when detecting that the application instance is unhealthy. In this way, the service traffic will not be directed to the application instance.
     Environment Variables	Environment variables are set in the container running environment and can be modified after application deployment to ensure the flexibility of applications. You can set environment variables as follows: On the Environment Variables tab page, click Add. Set Variable Name and Variable/Variable Reference.
     Data Storage	Stateless applications support upgrading of both local disks and cloud storage. Currently, stateful applications do not support upgrading of local disks or cloud storage.
     Security Context	Set container permissions to protect CCE and other containers from being affected. Enter a user ID. The container will run with this user ID.
     Log Policies	This parameter cannot be updated.

3. After the upgrade is completed, click Submit.

Monitoring an Application

After an application is created, you can go to the Monitoring page to monitor the CPU usage and memory usage of the container in which the application resides.

1. Log in to the CCE console. In the navigation pane, choose Application Management.
2. Click the name of the application to be monitored. The Application Details page is displayed.
3. Click the Instances tab. Click  next to an instance to be monitored and click Monitoring.
4. Check the CPU usage and memory usage of the instance.
   NOTE:

   CCE needs time to compute CPU usage. Therefore, when CPU and memory usage are displayed for the first time, CPU usage is displayed about one minute later than memory usage

   CPU and memory usage are displayed only for instances in the running state.

Adding Labels to Applications

Labels are attached to applications using key-value pairs. Applications with labels attached can be easily selected for setting affinity and anti-affinity scheduling rules. You can add labels to multiple applications or a specified application.

In the following figure, three labels release, env, and role are defined for the applications APP1, APP2, and APP3. The values of these labels vary with applications.

• Label of APP 1: [release:alpha;env:development;role:frontend]
• Label of APP 2: [release:beta;env:testing;role:frontend]
• Label of APP 3: [release:alpha;env:production;role:backend]

If you set key to role and value to frontend when using application scheduling or another function, the function will apply to APP1 and APP2.

Figure 1 Label example

1. In the navigation pane, choose Application Management.
2. Click the application for which a label is to be added. The Application Details page is displayed.
3. Click Manage Labels and Add Label, specify the key and value of the label that you want to create, and click OK.
   NOTE:

   A key-value pair must start and end with a letter or digit and consist of a maximum of 63 characters, including letters, digits, hyphens (-), underscores (_), and periods (.).