This is an error which does not normally appear at the high level. The action to take is application specific, and is detailed in the higher level error description.
A network session did not reach an application-defined stage within the allowed time interval.
Error Id: TNS-12502
Title: TNS:listener received no CONNECT_DATA from client
TNS:listener received no CONNECT_DATA from client
Check that the service name resolved from TNSNAMES.ORA has the CONNECT_DATA component of the connect descriptor.
No CONNECT_DATA was passed to the listener.
Error Id: TNS-12525
Title: TNS:listener has not received client’s request in time allowed
TNS:listener has not received client’s request in time allowed
If the error occurred because of a slow network or system, reconfigure INBOUND_CONNECT_TIMEOUT to a larger value. If a malicious client is suspected, use the address in listener.log to identify the source and restrict access. Turn on tracing for more information.
The listener disconnected the client because the client failed to provide the necessary connect information within the allowed time interval. This may be a result of network or system delays; or this may indicate that a malicious client is trying to cause a Denial of Service attack on the listener.
Error Id: TNS-12535
Title: TNS:operation timed out
TNS:operation timed out
Look at the documentation on the secondary errors for possible remedy. See SQLNET.LOG to find secondary error if not provided explicitly. Turn on tracing to gather more information.
The requested operation could not be completed within the time out period.
Error Id: TNS-12204
Title: TNS:received data refused from an application
TNS:received data refused from an application
Make sure that the application listener at the destination is functioning correctly. If it is and the problem persists, contact Worldwide Customer Support.
The application using Connection Manager refused the connection at the listener.