This topic describes how to manually or automatically execute a scaling rule to scale ECS instances.

Prerequisites

  • You have no overdue payments within your account.
    Notice If you have overdue payments within your account, all scaling activities fail to be executed. Make sure that you have sufficient balance within your account to ensure the service availability of Auto Scaling.
  • The scaling group to which the scaling rule belongs is in the Enabled state.
  • Scaling activities of the scaling group to which the scaling rule belongs meet the following requirements:
    • If the expected number of instances feature is disabled, no scaling activities are in progress in the scaling group.
    • If the expected number of instances feature is enabled, no non-parallel scaling activities are in progress in the scaling group. For more information, see Expected number of instances.

Background information

For information about the limits on the number of ECS instances in a scaling group, see Limits.

Manually execute a scaling rule

If you want to temporarily scale ECS instances, 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 time to expire. Within the cooldown time, Auto Scaling rejects only scaling activity requests triggered by event-triggered tasks from Cloud Monitor.
  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 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.
    • In the Actions column corresponding to the scaling group, click Details.
  5. In the upper part of the page, click the Scaling Rules tab.
  6. Find the scaling rule and click Execute in the Actions column.
  7. In the message that appears, click OK.

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 point in time. For information about how to create a scheduled task, 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 information about how to create an event-triggered task, see Create event-triggered tasks. For more information about event-triggered tasks, see Event-triggered task overview.
Note A target tracking scaling rule can be triggered only by the associated event-triggered task. For more information, see Create a scaling rule.