TNS-12502: TNS listener received no CONNECT_DATA from client

Hi,

Sometimes You can get “TNS-12502: TNS:listener received no CONNECT_DATA from client  ” error.

Details of error are as follows.

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

If you got this error,  it means your host definition in local_listener parameter is not correct, so fix it as follows.

Following description includes incorrect Host Definition as follows.

(DESCRIPTION = (ADDRESS_LIST = (ADDRESS = (PROTOCOL = TCP) (HOST = msdbadm01) (PORT = 1521))))

Fix and add the domain name and Correct Host Definition as follows.

(DESCRIPTION = (ADDRESS_LIST = (ADDRESS = (PROTOCOL = TCP) (HOST = msdbadm01.domain.local) (PORT = 1521))))

Run the following commands one by one on Node 1 and Node2 if you are using RAC, if not you can change it according to Single Instance.

SQL> alter system set local_listener='(DESCRIPTION=(ADDRESS_LIST=(ADDRESS=(PROTOCOL=TCP)(HOST=msdbadm01.domain.local)(PORT=1521))))' scope=both sid='MSDB1';

SQL> alter system set local_listener='(DESCRIPTION=(ADDRESS_LIST=(ADDRESS=(PROTOCOL=TCP)(HOST=msdbadm02.domain.local)(PORT=1521))))' scope=both sid='MSDB2';

Do you want to learn more details about RMAN, then read the following articles.

https://ittutorial.org/rman-backup-restore-and-recovery-tutorials-for-beginners-in-the-oracle-database/