This topic describes how to execute a scaling rule manually or automatically to scale Elastic Compute Service (ECS) instances.

Prerequisites

  • You have no overdue payments in your account.
    Notice If you have overdue payments in your account, all scaling activities will fail to be executed. Make sure that you have sufficient balance in your account to ensure the service availability of Auto Scaling.
  • The scaling group to which the scaling rule belongs is in the Enabled state.
  • The scaling group to which the scaling rule belongs has no scaling activities in progress.

Background information

The maximum number of ECS instances that a scaling group can have is not limited. However, the limits on ECS instance usage apply to Auto Scaling. For more information, see Limits.

Manually execute a scaling rule

If you need to scale ECS instances temporarily, you can manually execute a scaling rule.
Note If the scaling group has no scaling activities in progress, you can immediately execute the scaling rule without the need to wait for the cooldown period to expire.
  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 the target scaling group and use one of the following methods to open the details page of the scaling group:
    • Click the ID of the scaling group in the Scaling Group Name/ID column.
    • Click Manage in the Actions column.
  5. In the left-side navigation pane, click Scaling Rules.
  6. Find the target scaling rule and click Execute in the Actions column.
  7. Click Confirm.
    • If the scaling rule is executed, a success message appears in the upper-right corner of the page.
    • If the scaling rule fails to be executed, an error message appears.

Execute a scaling rule by using a scheduled task

If your business uses ECS instances on a regular basis, you can create a scheduled task to execute a scaling rule. Auto Scaling automatically executes the scaling rule at the specified time of point. For more information, see Create a scheduled task.

Execute a scaling rule by using an event-triggered task

If your business does not use ECS instances on a regular basis, you can create an event-triggered task to execute a scaling rule. When the specified condition is met, Auto Scaling automatically executes the scaling rule. For more information, see Create event-triggered tasks.
Note A target tracking scaling rule can be triggered only by the associated event-triggered task. For more information, see Create a scaling rule.
Event-triggered tasks are classified into system monitoring tasks and custom monitoring tasks to meet monitoring requirements in different scenarios. For more information, see Event-triggered task overview.
  • Configure a system monitoring taskExecute a scaling rule - Configure a system monitoring task
  • Configure a custom monitoring taskExecute a scaling rule - Configure a custom monitoring task