Help Center/ Distributed Database Middleware/ API Reference/ APIs (Recommended)/ DDM Instances/ Creating an Instance Group
Updated on 2026-06-05 GMT+08:00
View PDF
Share

Creating an Instance Group

Function

This API is used to create a DDM instance group.

Constraints

None

URI

  • URL format

    POST /v3/{project_id}/instances/{instance_id}/groups

  • Parameter description
    Table 1 URI parameters

    Parameter

    Mandatory

    Type

    Description

    project_id

    Yes

    String

    Project ID of a tenant in a region

    To obtain this value, see Obtaining a Project ID.

    instance_id

    Yes

    String

    DDM instance ID

Request Parameters

Table 2 Request header parameters

Parameter

Mandatory

Type

Description

X-Auth-Token

Yes

String

User token

You can obtain the token by calling the IAM API used to obtain a user token.
Table 3 Request body parameters

Parameter

Mandatory

Type

Description

name

Yes

String

Name of a DDM instance group, which:

  • Can include 4 to 64 characters.
  • Must start with a letter.
  • Can contain only letters, digits, underscores (_), and hyphens (-).

Minimum characters: 4

Maximum characters: 64

type

Yes

String

Type of the instance group.

rw: read/write group

r: read-only group

flavor_id

No

String

Flavor ID. (Either the flavor ID or flavor code must be specified.)

It can be obtained by referring to Querying DDM Node Classes Available in an AZ.

flavor_ref

No

String

Flavor code. (Either the flavor ID or flavor code must be specified.)

It can be obtained by referring to Querying DDM Node Classes Available in an AZ.

nodes

Yes

Array of Table NodeInfo objects

Node information list.

Minimum value: 1

Maximum value: 32
Table 4 NodeInfo

Parameter

Mandatory

Type

Description

available_zone

Yes

String

AZ where the node is located. The value cannot be empty. For details, see Regions and Endpoints.

subnet_id

Yes

String

Subnet ID.

Example Request

Create a DDM instance group. The group type is read/write and the number of nodes is 1.

POST https://{endpoint}/v3/{project_id}/instances/{instance_id}/groups
{
    "name": "group-1",
    "type": "rw",
    "flavor_id": "a615922f-0ed8-3691-aad4-a595185febba",
     "nodes": [
        {
            "available_zone": "az1", 
            "subnet_id": "ead1e945-ca89-45dd-bcce-4a30b2054c22"
        }
    ]
}

Create a DDM instance group. The group type is read-only and the number of nodes is 1.

POST https://{endpoint}/v3/{project_id}/instances/{instance_id}/groups
{
    "name": "group-2",
    "type": "r",
    "flavor_id": "a615922f-0ed8-3691-aad4-a595185febba",
     "nodes": [
        {
            "available_zone": "az1", 
            "subnet_id": "ead1e945-ca89-45dd-bcce-4a30b2054c22"
        }
    ]
}
Create a DDM instance group. The group type is read/write and the number of nodes is 2. 
POST https://{endpoint}/v3/{project_id}/instances/{instance_id}/groups
{
    "name": "group-3",
    "type": "rw",
    "flavor_id": "a615922f-0ed8-3691-aad4-a595185febba",
     "nodes": [
        {
            "available_zone": "az1", 
            "subnet_id": "ead1e945-ca89-45dd-bcce-4a30b2054c22"
        },
        {
            "available_zone": "az2", 
            "subnet_id": "ead1e945-ca89-45dd-bcce-4a30b2054c22"
        }
    ]
}

Response Parameters

  • Normal response
    Table 5 Response body parameters

    Parameter

    Type

    Description

    instance_id

    String

    DDM instance ID.

    job_id

    String

    ID of the job for creating an instance group.

    This parameter is returned only when pay-per-use instances are created.

    order_id

    String

    Order ID. This parameter is returned only when yearly/monthly instances are created.

    group_id

    String

    Group ID

    This parameter is returned only when pay-per-use instances are created.

Example Response

  • Normal response example

    Buying a pay-per-use instance:

    {
  "job_id": "3ae783f3-844e-4051-abd5-b9cc65899785",
  "group_id": "b4153b807b1a4f83870bf868fcc4f4ea****" 
}

    Buying a yearly/monthly instance:

    {
  "order_id" : "CS1810251738L8VVD"
}

Status Codes

Error Codes

For details, see Error Codes.

Parent topic: DDM Instances