Updated on 2025-12-15 GMT+08:00

Configuring an Autoscaling Policy

Function

This API is used to configure autoscaling for a DB instance. You will be billed for the new storage.

If available storage drops to a specified threshold or 10 GB, your storage will autoscale by 20% (in increments of 10 GB) of your allocated storage. If you have customized an autoscaling increment, the storage will autoscale by the specified increment.

Constraints

  • This API is in OBT. To use this API, contact customer service.
  • Your account balance must be greater than or equal to $0 USD. If your account balance is insufficient, autoscaling will fail.
  • This API is only available to instances whose storage type is cloud SSDs and storage space is at least 40 GB.
  • Storage autoscaling is unavailable when the instance is in any of the following statuses: upgrading to RDS, upgrading a minor version, and rebooting.
  • If a yearly/monthly instance has pending orders, it will not be autoscaled.
  • The storage space can be autoscaled up only when your instance status is Available or Storage full. The maximum allowed storage is 4,000 GB.

Authorization Information

Each account has all the permissions required to call all APIs, but IAM users must be assigned the required permissions.

  • If you are using identity policy-based authorization, the following identity policy-based permissions are required.

    Action

    Access Level

    Resource Type (*: required)

    Condition Key

    Alias

    Dependencies

    rds:instance:setAutoEnlargePolicy

    permission_management

    instance

    g:EnterpriseProjectId

    g:ResourceTag/<tag-key>

    rds:instance:modifyDns

    -

URI

  • URI format

    PUT /v3/{project_id}/instances/{instance_id}/disk-auto-expansion

  • Parameter description
    Table 1 Parameters

    Parameter

    Mandatory

    Type

    Description

    project_id

    Yes

    String

    Definition

    Project ID of a tenant in a region.

    For details about how to obtain the project ID, see Obtaining a Project ID.

    Constraints

    N/A

    Range

    N/A

    Default Value

    N/A

    instance_id

    Yes

    String

    Definition

    Instance ID.

    Constraints

    N/A

    Range

    N/A

    Default Value

    N/A

Request

Table 2 Parameters

Parameter

Mandatory

Type

Description

switch_option

Yes

Boolean

Definition

Whether to enable autoscaling.

Constraints

N/A

Range

  • true: indicates that autoscaling will be enabled.
  • false: indicates that autoscaling will be disabled.

Default Value

N/A

limit_size

No

Integer

Definition

Upper limit for autoscaling, in GB.

Constraints

This parameter is mandatory when switch_option is set to true.

Range

40 to 4000, in GB. The limit must be no less than the storage of the DB instance.

Default Value

N/A

trigger_threshold

No

Integer

Definition

Threshold to trigger autoscaling. If the available storage drops to this threshold or 10 GB, autoscaling is triggered.

Constraints

This parameter is mandatory when switch_option is set to true.

Range

Enumerated values:

  • 10
  • 15
  • 20

Default Value

N/A

step_percent

No

Integer

Definition

Autoscaling increment. It is the percentage of allocated storage that is automatically scaled up each time.

Constraints

This parameter is available when switch_option is set to true and autoscaling increment customization is enabled. If this parameter is not specified, the default value 20% is used.

Range

5%–50%

Default Value

20%

Example Request

Configure a storage autoscaling policy for a DB instance, with the trigger threshold set to 10% or 10 GB, upper limit to 4,000 GB, and autoscaling increment to 20%.
{
  "switch_option" : true,
  "limit_size" : 4000,
  "trigger_threshold" : 10,
  "step_percent" : 20
}

Response

Status Code