Updated on 2026-01-04 GMT+08:00

Scaling In a Cluster - ShrinkCluster

Function

This API is used to scale in an MRS cluster.

Constraints

None

Debugging

You can debug this API in API Explorer. Automatic authentication is supported. API Explorer can automatically generate sample SDK code and supports sample SDK code debugging.

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 role/policy-based authorization, see Permissions Policies and Supported Actions for details on 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

    Dependency

    mrs:cluster:resizeNodes

    Write

    cluster *

    • g:ResourceTag/<tag-key>

    • g:EnterpriseProjectId

    • mrs:cluster:resize

    -

URI

POST /v2/{project_id}/clusters/{cluster_id}/shrink

Table 1 URI parameters

Parameter

Mandatory

Type

Description

project_id

Yes

String

Explanation

Project ID.

Constraints

N/A

Value range

The value must consist of 1 to 64 characters. Only letters and digits are allowed.

Default value

N/A

cluster_id

Yes

String

Explanation

Cluster ID.

Constraints

N/A

Value range

The value can contain 1 to 64 characters, including only letters, digits, underscores (_), and hyphens (-).

Default value

N/A

Request Parameters

Table 2 Request body parameters

Parameter

Mandatory

Type

Description

node_group_name

Yes

String

Explanation

Node group name.

Constraints

N/A

Value range

The value can contain 1 to 64 characters, including only letters, digits, underscores (_), and hyphens (-).

Default value

N/A

count

No

Integer

Explanation

Number of nodes to be removed. If a specified node is to be removed, this parameter can be left blank.

Constraints

N/A

Value range

N/A

Default value

N/A

resource_ids

No

Array of strings

Explanation

Resource IDs of nodes to be removed during node scale-in. If this parameter is left blank, nodes are automatically removed based on system rules. Only abnormal ECS nodes can be removed. The specified nodes are forcibly removed. You can obtain the value of resource_id by calling the host API.

Constraints

N/A

Value range

N/A

Default value

N/A

Response Parameters

Status code: 200

Table 3 Response body parameter

Parameter

Type

Description

result

String

Explanation

Result of the request for updating a mapping.

Constraints

N/A

Value range

  • succeeded: The operation is successful.
  • failed: The operation failed.

Default value

N/A

Example Request

  • Remove a node from node group node_group_1.
    /v2/ff8080828997cb24018a1b2db3440b80/clusters/f7f45c04-4303-411c-9b71-d2cb730dd162/shrink 
      
     { 
       "node_group_name" : "node_group_1", 
       "count" : 1 
     }
  • Forcibly remove a node whose resource ID is 678050cd-ba1d-4550-942d-f2e396b1c6fb from node group node_group_1.
    /v2/ff8080828997cb24018a1b2db3440b80/clusters/f7f45c04-4303-411c-9b71-d2cb730dd162/shrink 
      
     { 
       "node_group_name" : "node_group_1", 
       "resource_ids" : [ "678050cd-ba1d-4550-942d-f2e396b1c6fb" ] 
     }

Example Response

Status code: 200

The scale-in is successful.

{
  "result" : "succeeded"
}

Status Codes

For details, see Status Codes.

Error Codes

For details, see Error Codes.