Last updated: 2021-06-16 16:45:32

1. API Description

Domain name for API request:

This API is used to reduce the specified number of instances from the scaling group, which returns the scaling activity ID ActivityId.

  • The scaling group is not active.
  • The scale-in instances will be selected according to the TerminationPolicies policy as described in Reducing Capacity.
  • Only the IN_SERVICE instances will be reduced. To reduce instances in other statues, use the DetachInstances or RemoveInstances API.
  • The desired capacity will be reduced accordingly. The new desired capacity should be no less than the minimum capacity.
  • If the scale-in activity failed or partially succeeded, the final desired capacity only deducts the instances that have been reduced successfully.

A maximum of 20 requests can be initiated per second for this API.

Note: This API supports Finance regions. If the common parameter Region is a Finance region, a domain name with the Finance region needs to be specified, for example:

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2. Input Parameters

The following request parameter list only provides API request parameters and some common parameters. For the complete common parameter list, see Common Request Parameters.

Parameter Name Required Type Description
Action Yes String Common parameter. The value used for this API: ScaleInInstances.
Version Yes String Common parameter. The value used for this API: 2018-04-19.
Region Yes String Common parameter. For more information, please see the list of regions supported by the product.
AutoScalingGroupId Yes String Scaling group ID
ScaleInNumber Yes Integer Number of instances to be reduced

3. Output Parameters

Parameter Name Type Description
ActivityId String Scaling activity ID
RequestId String The unique request ID, which is returned for each request. RequestId is required for locating a problem.

4. Example

Example1 This example shows you how to reduce one instance from the scaling group.

Input Example

Content-Type: application/json
X-TC-Action: ScaleInInstances
&<Common request parameters>

    "AutoScalingGroupId": "asg-12yqet78",
    "ScaleInNumber": 1

Output Example

  "Response": {
    "ActivityId": "asa-n6w01f6m",
    "RequestId": "c0bb46ea-2b47-471c-9099-e20bf7a23078"

5. Developer Resources


TencentCloud API 3.0 integrates SDKs that support various programming languages to make it easier for you to call APIs.

Command Line Interface

6. Error Code

The following only lists the error codes related to the API business logic. For other error codes, see Common Error Codes.

Error Code Description
InvalidParameterValue.InvalidAutoScalingGroupId Invalid scaling group ID.
InvalidParameterValue.Range The value is outside the specified range.
MissingParameter Parameter missing.
ResourceInsufficient.AutoScalingGroupBelowMinSize The number of instances in the auto scaling group is below the minimum value.
ResourceNotFound.AutoScalingGroupNotFound The scaling group does not exist.
ResourceUnavailable.AutoScalingGroupInActivity The auto scaling group is active.