Replacing a Read Replica with a Standby Node (RDS for SQL Server)

Function

This API is used to replace a read replica with a standby node.

• Before calling this API, learn how to authenticate it.
• Before calling this API, learn about request header parameters.

Authorization Information

Constraints

• If a read replica is faulty, the floating IP address of the read replica is temporarily assigned to the standby node to provide services. After the read replica recovers, you can choose to switch the IP address back to the read replica.
• Only the floating IP address of the read replica is assigned to the standby node. Due to the differences in the specifications, parameter settings, and replication latency between the standby node and the read replica, performance differences and data transition may occur. Operations such as switching between primary and standby nodes, changing specifications, and changing ports are not allowed. During the node replacement or switchback, workloads are briefly interrupted. This function is available only for RDS for SQL Server instances.
• To use this function, submit a service ticket to request required permissions.

URI

• URI format

  POST /v3/{project_id}/instances/{instance_id}/replace-node

• Parameter description

  Table 1 Parameters

  Parameter	Mandatory	Description
  project_id	Yes	Definition Project ID of a tenant in a region. To obtain the value, see Obtaining a Project ID. Constraints N/A Range N/A Default Value N/A
  instance_id	Yes	Definition Read replica ID. Constraints N/A Range N/A Default Value N/A

Request

Example Request

• Replace a read replica with a standby node.

  POST https://{Endpoint}/v3/5a7a69c429aa41b8a565c9a4995afea0/instances/02a202cf9fdd4561b80036337c9732f8in04/replace-node
  
  { 
     "instance_id" : "02a202cf9fdd4561b80036337c9732f8in04", 
     "node_id" : "bfafde30219f4ac5a820c7748e4dc106no04", 
     "replace_action" : "REPLACE" 
   }

• Switch back to the read replica.

  { 
     "instance_id" : "02a202cf9fdd4561b80036337c9732f8in04", 
     "node_id" : "bfafde30219f4ac5a820c7748e4dc106no04", 
     "replace_action" : "REPLACE_ROLLBACK" 
   }

Response

• Normal response

  Table 3 Parameters

  Parameter	Type	Description
  job_id	String	Definition Task flow ID. Range N/A

• Example normal response

  {
    "job_id": "5a7a69c429aa41b8a565c9a4995afea0"
  }

• Abnormal response

  For details, see Abnormal Request Results.

Status Code

• Normal

  200

• Abnormal

  For details, see Status Codes.

Error Code

For details, see Error Codes.