Updated on 2026-03-16 GMT+08:00

Creating a Read Replica

Function

This API is used to create a read replica. Before calling this API:

Learn how to authenticate it.
Obtain the required region and endpoint.

URI

URI format
POST https://{endpoint}/mysql/v3/{project_id}/instances/{instance_id}/nodes/enlarge
Example
POST https://{endpoint}/mysql/v3/0483b6b16e954cb88930a360d2c4e663/instances/dsfae23fsfdsae3435in01/nodes/enlarge

Parameter description

**Table 1** Parameter description
Name	Mandatory	Description
project_id	Yes	Project ID of a tenant in a region. To obtain this value, see Obtaining a Project ID.
instance_id	Yes	Instance ID, which is compliant with the UUID format.

Request

**Table 2** Parameter description
Name	Mandatory	Type	Description
priorities	Yes	List<Integer>	Failover priority of a read replica. Failover priority ranges from 1 for the first priority to 16 for the last priority. This priority determines the order in which read replicas are promoted when recovering from a primary node failure. Read replicas with the same priority have the same probability of being promoted to the new primary node.
is_auto_pay	No	String	Whether the order will be automatically paid after yearly/monthly instances are created. true: indicates the order will be automatically paid from your account. The default value is true. false: indicates the order will be manually paid.

Request example
```
{
"priorities":[1],

}
```

Response

Normal response

**Table 3** Parameter description
Name	Type	Description
instance_id	String	DB instance ID.
node_names	List<String>	Node name.
job_id	String	ID of the task for creating a read replica.
order_id	String	Order ID. This parameter is only returned for yearly/monthly instances.

Example normal response

{
    "instance_id":"f381d0b539e644df8f5b0d3a62129515in07",
    "node_names":["gauss-ccf5_node03"],
    "job_id":"0f6b6a9e-bd39-4e95-9374-e4d134e5a3d1"
}

Status Code

For details, see Status Codes.

Error Code

For details, see Error Codes.

Parent topic: Instance Management