Performs a failover between the primary node and a read-only node in a PolarDB cluster.

Debugging

OpenAPI Explorer automatically calculates the signature value. For your convenience, we recommend that you call this operation in OpenAPI Explorer. OpenAPI Explorer dynamically generates the sample code of the operation for different SDKs.

Request parameters

ParameterTypeRequiredExampleDescription
ActionStringNoFailoverDBCluster

The operation that you want to perform. Set the value to FailoverDBCluster.

DBClusterIdStringYespc-**************

The ID of the PolarDB cluster.

TargetDBNodeIdStringNopi-***********

The ID of the read-only node that serves as the new primary node. If you leave this parameter empty, the system automatically selects a read-only node. You can call the DescribeDBClusters operation to query node information, such as node IDs.

Note
  • If you leave this parameter empty, the system selects one or more nodes that have the highest priority from all the available read-only nodes. If the failover to the first read-only node fails due to network issues, abnormal replication status, or other reasons, the system tries to switch to another read-only node until the failover succeeds.
  • If the database engine of the PolarDB cluster is PolarDB for PostgreSQL(Compatible with Oracle) or the PolarDB for PostgreSQL, this parameter is required. If the database engine of the PolarDB cluster is the PolarDB for MySQL, this parameter is optional.
ClientTokenStringNo6000170000591aed949d0f54a343f1a4233c1e7d1c5******

The client token that is used to ensure the idempotence of the request. You can use the client to generate the value, but you must ensure that it is unique among different requests. The token can only contain ASCII characters and cannot exceed 64 characters in length. The token is case-sensitive.

Response parameters

ParameterTypeExampleDescription
RequestIdStringD0CEC6AC-7760-409A-A0D5-E6CD86******

The ID of the request.

Examples

Sample requests

http(s)://polardb.aliyuncs.com/?Action=FailoverDBCluster
&DBClusterId=pc-**************
&<Common request parameters>

Sample success responses

XML format

HTTP/1.1 200 OK
Content-Type:application/xml

<FailoverDBClusterResponse>
<RequestId>D0CEC6AC-7760-409A-A0D5-E6CD86******</RequestId>
</FailoverDBClusterResponse>

JSON format

HTTP/1.1 200 OK
Content-Type:application/json

{
  "RequestId" : "D0CEC6AC-7760-409A-A0D5-E6CD86******"
}

Error codes

For a list of error codes, visit the API Error Center.