Help Center/ Cloud Search Service/ API Reference/ API V1/ Modify Configuration/ Adding Instances and Expanding Instance Storage Capacity
Updated on 2025-11-28 GMT+08:00
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Adding Instances and Expanding Instance Storage Capacity

Function

If a cluster struggles to maintain performance in the face of rapid data growth or sustained high memory usage, you can add more nodes to it or increase the storage capacity of its existing nodes.

Constraints

  • The node storage capacity of a cluster can only be increased—not decreased. Select an appropriate node storage capacity based on the data volume and projected data growth.

  • For a pay-per-use cluster, you cannot increase the number of nodes and node storage capacity at the same time. For a yearly/monthly cluster, however, you cannot do that.

  • The storage capacity of the master and client nodes in a cluster cannot be expanded.

  • The storage capacity of data nodes that use local disks cannot be expanded.

  • For a Logstash cluster, you can only add more nodes, but cannot increase the storage capacity of its nodes.

Calling Method

For details, see Calling APIs.

URI

POST /v1.0/{project_id}/clusters/{cluster_id}/role_extend

Table 1 Path Parameters

Parameter

Mandatory

Type

Description

project_id

Yes

String

Definition:

Project ID. For details about how to obtain the project ID and name, see Obtaining the Project ID and Name.

Constraints:

N/A

Value range:

Project ID of the account.

Default value:

N/A

cluster_id

Yes

String

Definition:

ID of the cluster you want to scale out. For details about how to obtain the cluster ID, see Obtaining the Cluster ID.

Constraints:

N/A

Value range:

Cluster ID.

Default value:

N/A

Request Parameters

Table 2 Request body parameters

Parameter

Mandatory

Type

Description

grow

Yes

Array of RoleExtendGrowReq objects

Definition:

A detailed description of the cluster scale-out request.

Constraints:

N/A
Table 3 RoleExtendGrowReq

Parameter

Mandatory

Type

Description

type

Yes

String

Definition:

Type of the node to be added.

Constraints:

You can only add instances, rather than increase storage capacity, on nodes of the ess-master, ess-client, and lgs types.

Value range:

  • ess: data node

  • ess-master: master node

  • ess-client: client node

  • ess-cold: cold data node

  • lgs: Logstash nodes in Logstash clusters

You can select multiple node types, but cannot select the same node for different roles.

NOTE:
lgs cannot be combined with other options.

Default value:

N/A

nodesize

Yes

Integer

Definition:

Number of instances to be added.

Constraints:

After scaling, the number of nodes of each type must meet the following requirements:

  • Data nodes: If the cluster does not have master nodes, the value ranges from 1 to 32. Otherwise, the value ranges from 1 to 200.

  • Master nodes: 3, 5, 7, or 9 (must be an odd number from 3 to 9)

  • Client nodes: 1 to 64.

  • Cold data nodes: 1 to 32.

  • Logstash nodes: 1 to 100.

Value range:

See Constraints.

Default value:

N/A

disksize

Yes

Integer

Definition:

Storage capacity to be added, in GB.

Constraints:

The sum of the original instance storage capacity plus the expanded instance storage capacity cannot exceed the default upper limit of storage capacity set during cluster creation. If there is no need to add more instances, set this parameter to 0. With a yearly/monthly cluster, you cannot change the number of nodes and disk capacity at the same time.

Value range:

  • The scale-out step of ESS and ESS-cold nodes is 20.

  • Storage capacity of ess-master and ess-client nodes cannot be expanded.

  • Logstash does not support storage capacity expansion.

  • Multiple constraints are put in different rows in random order.

Default value:

N/A

Response Parameters

Status code: 200

Table 4 Response body parameters

Parameter

Type

Description

id

String

Definition:

Cluster ID.

Value range:

N/A

Example Requests

Change the number of instances and storage capacity of the current cluster.

POST https://{Endpoint}/v1.0/{project_id}/clusters/4f3deec3-efa8-4598-bf91-560aad1377a3/role_extend

{
  "grow" : [ {
    "type" : "ess-master",
    "nodesize" : 2,
    "disksize" : 0
  }, {
    "type" : "ess",
    "nodesize" : 0,
    "disksize" : 40
  }, {
    "type" : "ess-client",
    "nodesize" : 1,
    "disksize" : 0
  }, {
    "type" : "ess-cold",
    "nodesize" : 1,
    "disksize" : 0
  } ],
  "is_auto_pay" : 1
}

Example Responses

Status code: 200

Request succeeded.

{
  "id" : "4f3deec3-efa8-4598-bf91-560aad1377a3"
}

Status Codes

Status Code

Description

200

Request succeeded.

400

Invalid request.

Modify the request before retry.

404

The requested resource could not be found.

Modify the request before retry.

Error Codes

See Error Codes.

Parent topic: Modify Configuration