This topic describes how to modify a scaling group. If your scaling group no longer meets your business requirements, you can simply modify one or more parameter settings of the scaling group. You do not need to create a new scaling group.

Background information

Before you modify a scaling group, take note of the following items:

  • You cannot change the network type of a scaling group.
  • If the network type of a scaling group is VPC, you can change the vSwitch, but you cannot change the instance reclaim mode.

Procedure

  1. Log on to the Auto Scaling console.
  2. In the top navigation bar, select a region.
  3. In the left-side navigation pane, click Scaling Groups.
  4. Find the scaling group that you want to modify and click Edit in the Actions column.
  5. Modify the parameter settings of the scaling group.

    For more information about the parameters of a scaling group, see Create a scaling group.

    When you modify the parameter settings, take note of the following items:

    • If the number of existing Elastic Compute Service (ECS) instances in the scaling group falls outside the specified range after you modify the Maximum Number of Instances and Minimum Number of Instances settings, Auto Scaling automatically adds or removes ECS instances to ensure that the number of ECS instances in the scaling group is within the specified range.
    • If the number of instances is less than the minimum number of instances in the scaling group with the Expected Number of Instances feature disabled after you manually modify the Minimum Number of Instances settings, Auto Scaling automatically adds instances to the scaling group to ensure that the actual number of instances is equal to or greater than the minimum number of instances.
    • If the number of instances is inconsistent with the expected number of instances in the scaling group after you manually modify the Expected Number of Instances settings, Auto Scaling automatically adds instances to the scaling group to reach the expected number of instances.
    • When you change the ApsaraDB RDS instance that is associated with a scaling group that contains ECS instances, select When you associate ApsaraDB RDS instances with or disassociate ApsaraDB RDS instances from the scaling group, existing ECS instances in the scaling group are added to or removed from the whitelists of the ApsaraDB RDS instances based on your business requirements.
      • If you select this option, Auto Scaling automatically adds the IP addresses of the existing ECS instances to the whitelist that manages access to the ApsaraDB RDS instance that you associate with the scaling group, or Auto Scaling automatically removes the IP addresses of the existing ECS instances from the whitelist that manages access to the ApsaraDB RDS instance that you disassociate from the scaling group.
      • If you do not select this option, the whitelist that manages access to the ApsaraDB RDS instance remains unchanged when you associate the ApsaraDB RDS instance with the scaling group or disassociate the ApsaraDB RDS instance from the scaling group.
    • When you change the Server Load Balancer (SLB) instances that are associated with a scaling group that contains ECS instances, select When you associate SLB instances with or disassociate SLB instances from the scaling group, existing ECS instances in the scaling group are added to or removed from the server groups of the SLB instances based on your business requirements. SLB instances include the Application Load Balancer (ALB) server group and the Classic Load Balancer (CLB) instance.
      • If you select this option, Auto Scaling automatically adds the existing ECS instances to the backend server groups of the SLB instances that you associate with the scaling group, or Auto Scaling automatically removes the existing ECS instances from the backend server groups of the SLB instances that you disassociate from the scaling group.
      • If you do not select this option, the backend server groups of the SLB instances remain unchanged when you associate the SLB instances with the scaling group or disassociate the SLB instances from the scaling group.
  6. Click OK.