This topic describes how to put an Elastic Compute Service (ECS) instance that is not needed for the moment into the Standby state. After an ECS instance is put into the Standby state, the Server Load Balancer (SLB) weight value of the ECS instance changes to zero. If an ECS instance is in the Standby state, Auto Scaling does not check its health status or release it.

Background information

After an ECS instance is put into the Standby state:
  • If an SLB instance is associated with the scaling group to which the ECS instance belongs, the SLB weight value of the ECS instance changes to zero.
  • The ECS instance stays in the Standby state until you manually move it out of the Standby state.
  • Auto Scaling stops managing the lifecycle of the ECS instance. You must manually manage the lifecycle of the ECS instance.
  • If a scale-in event is triggered, Auto Scaling does not remove the ECS instance.
  • When the ECS instance is stopped or restarted, its health check status remains unchanged.
  • To release the ECS instance, you must first remove it from the scaling group.
  • If you delete the scaling group to which the ECS instance belongs, the instance is automatically moved out of the Standby state and removed from the scaling group.
    Note If the lifecycle of the ECS instance is managed by the scaling group, the instance is released. Otherwise, the instance is not released and can run normally. For more information about the lifecycle management of ECS instances, see ECS instance lifecycle in a scaling group.
  • You can stop the ECS instance or change its configurations. For example, you can perform the following operations:

Procedure

  1. Log on to the Auto Scaling console.
  2. In the left-side navigation pane, click Scaling Groups.
  3. In the top navigation bar, select a region.
  4. Find a scaling group and go to the details page of the scaling group. You can use one of the following methods to go to the details page:
    • Click the ID of the scaling group in the Scaling Group Name/ID column.
    • Click Details in the Actions column of the scaling group.
  5. In the upper part of the page, click the Instances tab.
  6. Select the source of an ECS instance.
    • To select an ECS instance that is automatically created, click the Auto Created tab.
    • To select an ECS instance that is manually added, click the Manually Added tab.
  7. Use one of the following methods to put one or more ECS instances into the Standby state:
    • Find the ECS instance that you want to put into the Standby state and click Switch to Standby in the Actions column.
    • Select multiple ECS instances that you want to put into the Standby state and click Switch to Standby in the lower part of the Instances page.
  8. In the message that appears, click OK.