OCI-12516
Cannot connect to database. Listener at host_port does not have a protocol handler for protocol_stack ready or registered for service service_name. (CONNECTION_ID=connection_id)
- host_port: The host and port that the Oracle Database listener process is on.
- protocol_stack: The requested protocol stack.
- service_name: The name of the database service.
- connection_id: The connection ID.
Cause
The connection was refused by the Oracle Database listener process. None of the known and available service handlers for the specified service name support the client's requested protocol stack.
Action
Do the following:
- Check for mistakes in the specified connection string.
- If you are using a cloud service, review the connection string shown in the service console.
- Wait a moment and try to connect again. The service handler may be in a blocked state and not accepting new connections.
- Use the CONNECTION_ID value to track this connection attempt in trace files for further diagnosis.
To find which handlers are currently known by the listener and are accepting connections, do the following:
- Ask your Database Administrator.
- Review the connection string shown in the cloud service console.
- If you have access to the machine where the listener is running, you can run one of the following:
- lsnrctl services
- When a listener is named in the listener.ora file, run: lsnrctl services <listener_name>
- If an Oracle Connection Manager (Oracle CMAN) proxy listener is named in the cman.ora file, run: cmctl show services -c <cman_name>
- If an Oracle Global Service Manager (Oracle GSM) listener is named in the gsm.ora file, run: gdsctl services -raw -gsm <gsm_name>
- Ensure that the registered handlers are configured to support the desired protocol stack, for example, to match the protocol, session, and presentation used in the connection string.