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Adding Nodes for a Cluster Instance

Function

This API is used to add nodes for a specified cluster instance.

Constraints

  • This API supports only pay-per-use Community Edition DB instances.
  • Only the mongos and shard nodes can be added.
  • The specifications of the new node must be the same as those of the existing nodes in the instance.

    The specification series includes general-purpose (s6), enhanced (c3), and enhanced II (c6).

    Example:
    • dds.mongodb.s6.large.4.mongos and dds.mongodb.s6.medium.4.mongos have the same specifications.
    • dds.mongodb.s6.large.4.mongos and dds.mongodb.c3.large.4.mongos are not of the same specifications.

URI

  • URI format

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

  • Parameter description
    Table 1 Parameter description

    Name

    Mandatory

    Description

    project_id

    Yes

    Specifies the project ID of a tenant in a region.

    instance_id

    Yes

    Specifies the DB instance ID.

Requests

  • Parameter description
    Table 2 Parameter description

    Name

    Mandatory

    Type

    Description

    type

    Yes

    String

    Specifies the object to be scaled.

    • Set the value to mongos if mongos nodes are to be added.
    • Set the value to shard if shard nodes are to be added.

    spec_code

    Yes

    String

    Specifies the resource specification code. For details about how to obtain the resource specification code, see the flavors.spec_code parameter in Querying All DB Instance Specifications.

    num

    Yes

    Integer

    Specifies the number of mongos or shard nodes to be added. A cluster instance supports a maximum of 32 mongos nodes and 32 shard nodes.

    volume

    No

    Object

    Specifies the volume information. For more information, see Table 3.

    • This parameter is not transferred when the mongos nodes are to be added.
    • This parameter is mandatory when the shard nodes are to be added. The disk information of all shards to be added needs to be specified.
      NOTE:

      If multiple shards are added at a time, the shards must have the same specifications and disk capacity.
    Table 3 volume field data structure description

    Name

    Mandatory

    Type

    Description

    size

    Yes

    Integer

    Specifies the disk capacity of all new shards. The value range is from 10 GB to 2000 GB.
  • Request header 
    POST https://DDS endpoint/v3/{project_id}/instances/{instance_id}/enlarge
  • Example request
    Number of mongos nodes to be added: 
    { 
	"type": "mongos",
	"spec_code":"dds.c3.medium.4.mongos",
	"num": 1
}
    Number of shard nodes to be added: 
    {
	"type": "shard",
	"spec_code":"dds.c3.medium.4.shard",
	"num": 1,
        "volume": { 
             "size": 330 
    }
}

Responses

  • Parameter description
    Table 4 Parameter description

    Name

    Type

    Description

    job_id

    String

    Indicates the task ID.
  • Response example 
    { 
    "job_id": "4008c8914b624785a02ab7966d4d" 
}

Status Code

For more information, see Status Code.

Error Code

For more information, see Error Code.

Parent topic: DB Instance Management