TNS-12502: TNS: listener received no CONNECT_DATA from client, ftpclient. connect

TNS-12502: TNS: listener received no CONNECT_DATA from client, ftpclient. connect

Check the listening logs of one of our ORACLE databases and find many TNS-12502 error messages. As shown below

TNS-12502: TNS:listener received no CONNECT_DATA from client

09-DEC-2014 15:47:06 * (CONNECT_DATA=(SERVICE_NAME=epps)(CID=(PROGRAM=D:\Tasks\FGIS2MES\CEG\gmt_auto.exe)(HOST=CEGWEB1)(USER=cegadmin))) * (ADDRESS=(PROTOCOL=tcp)(HOST=192.163.21.14)(PORT=2312)) * establish * epps * 0

$ Oerr tns 12502

12502,000 00, "TNS: listener received no CONNECT_DATA from client"

// * Cause: No CONNECT_DATA was passed to the listener.

// * Action: Check that the service name resolved from TNSNAMES. ORA has

// The CONNECT_DATA component of the connect descriptor.

Generally, this error occurs because the client tnsnames. ora does not contain CONNECT_DATA, but as shown above, the client tnsnames. ora already contains CONNECT_DATA data, which is normal in most cases, but occasionally in listener. the error message is found in the log, and there is no law at all, and finally in the Oracle TNS-12502 error cause and solution this article learned that the client through telnet database server port 1521 test connectivity, the following error occurs. As follows:

Telnet 192.168.20.11 1521

View/u01/app/oracle/product/10.2.0/db_1/network/log/listener. log as shown below, you will see the TNS-12525 error message.

12-DEC-2014 20:40:33 * <unknown connect data> * (ADDRESS = (PROTOCOL = tcp) (HOST = 192.168.125.113) (PORT = 52651) * establish * <unknown sid> * 12525

TNS-12525: TNS: listener has not supplied ed client's request in time allowed

TNS-12535: TNS: operation timed out

TNS-12606: TNS: Application timeout occurred

12-DEC-2014 20:40:37 * service_update * epps * 0

But this is different from the error message found in the listening log: TNS-12502: TNS: listener received ed no CONNECT_DATA from client, I 've counted the timing of TNS-12502 errors and it's hard to find out what's going on. It is strange that this error does not affect your use. So far, I have not figured out why this error occurs. Keep a record for future research and solutions!

References:

Http://www.eygle.com/archives/2006/08/oracle_tns_12502.html