Updated on 2026-09-22 GMT+08:00

Configuring an Automatic Scale-out Policy

Function

This API is used to configure an automatic scale-out policy.

Constraints

This API can be used for GeminiDB Cassandra instances.

This API supports both pay-per-use and yearly/monthly instances.

By default, fees are automatically deducted for yearly/monthly instances.

Autoscaling is available only when your account balance is sufficient.

If the instance status is not normal, the policy for automatically adding nodes cannot be configured.

Authorization Information

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

If you are using role/policy-based authorization, see the required permissions in Permissions and Supported Actions.

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
gaussdbfornosql:instance:setAutoNodeExpansionPolicy	write	instance *	g:ResourceTag/<tag-key> g:EnterpriseProjectId	nosql:instance:extendNode	-

URI

PUT /v3/{project_id}/instances/{instance_id}/node-auto-expansion-policy

**Table 1** URI parameters
Parameter	Mandatory	Type	Description
project_id	Yes	String	Definition Project ID of a tenant in a region. To obtain this value, see Obtaining a Project ID. Constraints N/A Range The value contains 32 characters. Only letters and digits are allowed. Default Value N/A
instance_id	Yes	String	Definition Instance ID. To obtain the value, call the Querying Instances and Details API. If no instance is available, call the Creating an Instance API to create one. Constraints N/A Range N/A Default Value N/A

Request Parameters

**Table 2** Request header parameters
Parameter	Mandatory	Type	Description
X-Auth-Token	Yes	String	Definition User token You can obtain the token by calling the IAM API by following Obtaining a User Token Through Password Authentication. Constraints N/A Range N/A Default Value N/A

**Table 3** Request body parameters
Parameter	Mandatory	Type	Description
switch_option	Yes	Boolean	Definition Whether the switch for automatically adding nodes is enabled Constraints N/A Range true: enabled false: disabled Default Value N/A
overload_node_threshold	No	Integer	Definition Percentage of overloaded nodes. For example, if there are three nodes in the current instance and the policy needs to be triggered when a threshold is reached for two of them, the value can be 67% (= 2/3; rounded up). Constraints N/A Range An integer ranging from 1 to 100 Default Value N/A
cpu_threshold	No	Integer	Definition CPU usage of nodes for which autoscaling is triggered Constraints N/A Range An integer ranging from 1 to 100 Default Value 80
mem_threshold	No	Integer	Definition Memory usage of nodes for which autoscaling is triggered Constraints N/A Range An integer ranging from 1 to 100 Default Value 80
step	No	Integer	Definition Number of nodes to be added each time Constraints N/A Range The value is a positive integer greater than or equal to 1. The maximum value cannot exceed the upper limit of nodes that can be added. Default Value 3
node_limit	No	Integer	Definition Maximum number of nodes that can be automatically added Constraints N/A Range The value is a positive integer greater than or equal to 1. The maximum value cannot exceed the upper limit of nodes that can be added to the current instance. Default Value The default value is the maximum number of nodes that can be added to the current instance.

Response Parameters

Status code: 200

Example Requests

Configuring a policy for automatically adding nodes

PUT https://{endpoint}/v3/054e292c9880d4992f02c0196d3ea468/instances/3d39c18788b54a919bab633874c159dfin02/node-auto-expansion-policy    
{    
  "switch_option" : true, 
  "overload_node_threshold" : 50,  
  "cpu_threshold" : 80,  
  "mem_threshold" : 80,  
  "step" : 3,  
  "node_limit" : 10 
 }

Example Responses

None

Status Codes

See Status Codes.

Error Codes

See Error Codes.

Parent topic: Instances