Auto Scaling:Use Alibaba Cloud CLI to execute rolling update tasks

Procedure

Step 1: Create a RAM user and grant permissions to the RAM user

1. Log on to the Resource Access Management (RAM) console.

2. Create a RAM user.

   In this example, a RAM user named clitest is created. For more information, see Create a RAM user.

   1. In the left-side navigation pane, choose Identities > Users.

   2. On the Users page, click Create User.

   3. On the Create User page, configure parameters as prompted and click OK.

      The following table describes the parameter settings used in this example.

      Parameter	Description
      Logon Name	example@sample.com
      Display Name	example
      Access Mode	Select Open API Access. An AccessKey pair is automatically created for the RAM user. The RAM user can call API operations or use SDKs to access Alibaba Cloud resources.

   4. On the User Information page, click Download CSV File.

      Note

      The AccessKey secret is displayed only when you create an AccessKey pair, and cannot be queried. We recommend that you save the AccessKey secret for subsequent use. If an AccessKey pair is leaked or lost, you must create a new AccessKey pair.

3. Grant the RAM user permissions to manage resources.

   1. In the left-side navigation pane, choose Identities > Users.

   2. Find the clitest user that you created and click Add Permissions in the Actions column.

   3. In the Grant Permission panel, select the permissions required to execute the rolling update task and click Grant permissions.

      The following table describes the parameter settings used in this example.

      Parameter	Description
      Resource Scope	Set the value to Account.
      Principal	Set the value to example@sample.com.
      Policy	Select the following system policies: AliyunECSFullAccess: grants permissions to manage ECS resources, such as ECS instances. AliyunESSFullAccess: grants permissions to manage Auto Scaling resources, such as scaling groups. AliyunOOSFullAccess: grants permissions to manage OOS resources, such as executions.CloudOps Orchestration Service AliyunOSSFullAccess: grants permissions to manage Object Storage Service (OSS) resources, such as buckets.

Step 2: Configure and verify Alibaba Cloud CLI

For information about the configuration parameters, see Configure Alibaba Cloud CLI.

1. Open Alibaba Cloud CLI on your on-premises computer.

2. Configure Alibaba Cloud CLI.

   1. Run the following command to open the configuration file:

      aliyun configure

   2. Enter the AccessKey ID and AccessKey secret as prompted.

      

3. Run the following command to check whether Alibaba Cloud CLI is available:

   aliyun ecs DescribeRegions

   This command is used to query the regions in which Alibaba Cloud CLI is supported. If region information is returned, the command is successfully run. The following figure shows a sample command output.

Step 3: Use Alibaba Cloud CLI to execute a rolling update task

In this step, sample commands are used to show how to update images, run scripts, and install OOS packages on ECS instances in a scaling group.

1. Run an Alibaba Cloud CLI command to execute a rolling update task.

   For information about the OOS template parameters in the code, see Template parameters.

   • The following sample code provides an example on how to update the images of ECS instances in the scaling group to Alibaba Cloud Linux 2.1903 LTS 64-bit:

     aliyun oos StartExecution --TemplateName ACS-ESS-RollingUpdateByReplaceSystemDiskInScalingGroup --Parameters "{
             \"invokeType\": \"invoke\",
             \"scalingGroupId\": \"asg-bp18p2yfxow2dloq****\",
             \"scalingConfigurationId\": \"asc-bp1bx8mzur534edp****\",
             \"imageId\": \"aliyun_2_1903_x64_20G_alibase_20200529.vhd\",
             \"sourceImageId\": \"centos_7_8_x64_20G_alibase_20200717.vhd\",
             \"OOSAssumeRole\": \"\",
             \"enterProcess\": [
               \"ScaleIn\",
               \"ScaleOut\",
               \"HealthCheck\",
               \"AlarmNotification\",
               \"ScheduledAction\"
             ],
             \"exitProcess\":  [
               \"ScaleIn\",
               \"ScaleOut\",
               \"HealthCheck\",
               \"AlarmNotification\",
               \"ScheduledAction\"
             ],
             \"batchNumber\": 2,
             \"batchPauseOption\": \"Automatic\"
           }"

   • The following sample code provides an example on how to run the df -h and ifconfig shell commands on the ECS instances in the scaling group to view the disks and network configurations of the ECS instances:

     aliyun oos StartExecution --TemplateName ACS-ESS-RollingUpdateByRunCommandInScalingGroup --Parameters "{
             \"invokeType\": \"invoke\",
             \"scalingGroupId\": \"asg-bp18p2yfxow2dloq****\",
             \"commandType\": \"RunShellScript\",
             \"invokeScript\": \"df -h\nifconfig\",
             \"rollbackScript\": \"df -h\nifconfig\",
             \"OOSAssumeRole\": \"\",
             \"exitProcess\": [
               \"ScaleIn\",
               \"ScaleOut\",
               \"HealthCheck\",
               \"AlarmNotification\",
               \"ScheduledAction\"
             ],
             \"enterProcess\": [
               \"ScaleIn\",
               \"ScaleOut\",
               \"HealthCheck\",
               \"AlarmNotification\",
               \"ScheduledAction\"
             ],
             \"batchNumber\": 2,
             \"batchPauseOption\": \"Automatic\"
           }"

   • The following sample code provides an example on how to install the WordPress software package created in an OOS template on the ECS instances in the scaling group:

     aliyun oos StartExecution --TemplateName ACS-ESS-RollingUpdateByConfigureOOSPackage --Parameters "{
             \"invokeType\": \"invoke\",
             \"scalingGroupId\": \"asg-bp18p2yfxow2dloq****\",
             \"packageName\": \"wordpress\",
             \"packageVersion\": \"v4\",
             \"action\": \"install\",
             \"OOSAssumeRole\": \"\",
             \"enterProcess\": [
               \"ScaleIn\",
               \"ScaleOut\",
               \"HealthCheck\",
               \"AlarmNotification\",
               \"ScheduledAction\"
             ],
             \"exitProcess\": [
               \"ScaleIn\",
               \"ScaleOut\",
               \"HealthCheck\",
               \"AlarmNotification\",
               \"ScheduledAction\"
             ],
             \"batchNumber\": 2,
             \"batchPauseOption\": \"Automatic\"
           }"

2. View the execution details.

   When you run CLI commands to execute rolling update tasks, executions are automatically created in OOS. You can find the desired execution based on the returned execution ID and view the details of the execution, such as the execution result and output. The following example shows how to obtain the execution ID and view the execution details:

   1. Find the execution ID of the rolling update task in the command output.

      The following figure shows a sample execution ID.

   2. Run the following Alibaba Cloud CLI command to view the execution details:

      aliyun oos ListExecutions --ExecutionId exec-40e2e17ef7e04****

      The following figure shows the details of a sample execution.

Execute rollback tasks to handle exceptions in rolling update tasks

If exceptions occur when rolling update tasks are executed, or if you want to use previous configurations after rolling update tasks are executed, you can execute rollback tasks to restore the configurations of ECS instances. In this section, sample commands are used to show how to roll back rolling update tasks that are executed.

1. Find the execution ID of the rolling update task in the command output.

   The following figure shows a sample execution ID.

2. Run an Alibaba Cloud CLI command to execute a rollback task.

   For information about the OOS template parameters in the code, see Template parameters.

   Note

   When you execute a rollback task, OOS automatically finds the ECS instances that need to be rolled back based on the rolling update task, and suspends or resumes scaling processes in the scaling group. Therefore, you may not need to configure some parameters.

   • The following sample code provides an example on how to roll back the images of the ECS instances in the scaling group to CentOS 7.8 64-bit:

     aliyun oos StartExecution --TemplateName ACS-ESS-RollingUpdateByReplaceSystemDiskInScalingGroup --Parameters "{
             \"invokeType\": \"rollback\",
             \"scalingGroupId\": \"asg-bp18p2yfxow2dloq****\",
             \"scalingConfigurationId\": \"asc-bp1bx8mzur534edp****\",
             \"sourceImageId\": \"centos_7_8_x64_20G_alibase_20200717.vhd\",
             \"sourceExecutionId\": \"exec-83dba59be77d430****\",
             \"OOSAssumeRole\": \"\",
             \"batchNumber\": 2,
             \"batchPauseOption\": \"Automatic\"
           }"

   • The following sample code provides an example on how to run the rollback script on the ECS instances:

aliyun oos StartExecution --TemplateName ACS-ESS-RollingUpdateByRunCommandInScalingGroup --Parameters "{
        \"invokeType\": \"rollback\",
        \"commandType\": \"RunShellScript\",
        \"rollbackScript\": \"df -h\nifconfig\",
        \"scalingGroupId\": \"asg-bp18p2yfxow2dloq****\",
        \"sourceExecutionId\": \"exec-40e2e17ef7e046****\",
        \"OOSAssumeRole\": \"\",
        \"batchNumber\": 2,
        \"batchPauseOption\": \"Automatic\"
      }"

• The following sample code provides an example on how to roll back the WordPress software package created in the OOS template on the ECS instance to its previous version:

  aliyun oos StartExecution --TemplateName ACS-ESS-RollingUpdateByConfigureOOSPackage --Parameters "{
          \"invokeType\": \"rollback\",
          \"scalingGroupId\": \"asg-bp18p2yfxow2dloq****\",
          \"packageVersion\": \"v3\",
          \"packageName\": \"wordpress\",
          \"sourceExecutionId\": \"exec-f4e61f2f21fe490****\",
          \"OOSAssumeRole\": \"\",
          \"batchNumber\": 2,
          \"batchPauseOption\": \"Automatic\"
        }"

• View the execution details.

  When you run CLI commands to execute rollback tasks, executions are automatically created in OOS. You can also use the methods in Step 3 to view the details of an execution, such as the execution result and output.

Template parameters