Adding a Read Replica to an Instance

API Description

This API is used to add read replicas to DDS replica set instances.

Restrictions

• Currently, this API only supports replica set instances and cluster instances 3.4.
• A maximum of five read replicas can be added to a replica set instance.
• In a cluster instance, up to five read replicas can be added to a shard.
• In a cluster instance, read replicas can be added to only one shard at a time.
• The synchronization delay cannot be set for cluster instances. The default value is 0.
• This API supports both yearly/monthly and pay-per-use DB instances.

URI

• URI format

  POST https://{Endpoint}/v3/{project_id}/instances/{instance_id}/readonly-node

• URI example
  https://dds.cn-north-1.myhuaweicloud.com/v3/0549b4a43100d4f32f51c01c2fe4acdb/instances/9136fd2a9fcd405ea4674276ce36dae8in02/readonly-node

  Table 1 Request parameters

  Name	Mandatory	Type	Description
  project_id	Yes	String	Project ID of a tenant in a region. To obtain the project ID, see Obtaining a Project ID.
  instance_id	Yes	String	Instance ID, which can be obtained by calling the API described in Querying Instances and Details. If you do not have an instance, call the API described in Creating a DB Instance to create one.

  Table 2 Request header parameters

  Name	Mandatory	Type	Description
  X-Auth-Token	Yes	String	User token obtained from IAM. For details, see Authentication.

Request Parameters

• Parameter description

  Table 3 Request body parameters

  Name	Mandatory	Type	Description
  spec_code	Yes	String	The resource specification code. For details about how to obtain the value, see the parameter value in Querying Database Specifications. Example: dds.mongodb.c6.large.4.rr
  num	Yes	Integer	Number of read replicas to be added. The value ranges from 1 to 5.
  delay	No	Integer	Synchronization delay. The value ranges from 0 to 1200, in milliseconds. The default value is 0.
  is_auto_pay	No	Boolean	Whether the order is automatically paid from your account when you add read replicas to a yearly/monthly DB instance. This parameter does not affect the payment mode of automatic renewal. true: indicates that the order is automatically paid from the account. false: indicates that the order is manually paid from the account. The default value is false.

Example Request

Adding one read replica who spec_code is set to dds.mongodb.c6.large.4.rr, and delay is set to 0

POST https://dds.cn-north-1.myhuaweicloud.com/v3/0549b4a43100d4f32f51c01c2fe4acdb/instances/9136fd2a9fcd405ea4674276ce36dae8in02/readonly-node 
 
{  
    "spec_code": "dds.mongodb.c6.large.4.rr",
    "num" : 1,  
    "delay" : 0 
}

Response Parameters

Response Example

{ 
  "job_id" : "4008c8914b624785a02ab7966d4d" 
}

Status Code

For details, see Status Code.

Error Code

For details, see Error Code.