OPC-UA Action

The OPC-UA action writes values to variable nodes on OPC-UA servers through opc.tcp:// connections.

Properties

Property Name	Optional	Description
endpoint	false	OPC-UA server URL (e.g. opc.tcp://192.168.1.100:4840).
nodeId	false	Target OPC-UA NodeId string (e.g. ns=2;s=Device1.TargetSpeed or ns=1;i=1001).
field	false	The field name in the output record whose value should be written.
username	true	Optional username credential for user token authentication.
password	true	Optional password credential for user token authentication.
timeout	true	Socket and write request timeout (e.g. 1000ms). Default: 1000ms.

Other common sink properties are supported. Refer to sink common properties for more information.

Example

{
  "id": "rule_opcua_control",
  "sql": "SELECT setpoint FROM temperature_alerts WHERE setpoint IS NOT NULL",
  "actions": [
    {
      "opcua": {
        "endpoint": "opc.tcp://192.168.1.100:4840",
        "nodeId": "ns=2;s=HeaterController.TargetTemp",
        "field": "setpoint",
        "timeout": "2000ms"
      }
    }
  ]
}

Dead-Letter Queue (DLQ) Integration

When an OPC-UA write fails with permanent status codes:

• BadNodeIdUnknown (0x80340000)
• BadTypeMismatch (0x803C0000)
• BadNotWritable (0x803B0000)

The connector classifies the error as permanent. It sends the output record to the dead-letter queue under DlqStage::SinkDelivery. For configuration options, refer to Dead-Letter Queues.