When we face "ORA-12170: TNS Connect timeout occurred", then immediately check the following
- TNS_ADMIN environment variable is defined or not
- ORACLE_HOME environment variable is defined as "C:\oraclexe\app\oracle\product\11.2.0\server".
- "C:\oraclexe\app\oracle\product\11.2.0\server\Network\Admin\sqlnet.ora" was located NAMES.DIRECTORY_PATH specifies EZCONNECT in the sqlnet.ora file
- EZCONNECT is not the first naming method in NAMES.DIRECTORY_PATH which may conflict with other naming methods specified
Steps need to follow to fix the issue
- Try moving EZCONNECT to the first position in NAMES.DIRECTORY_PATH in the sqlnet.ora file
- Verify that the database server is running
- The following profile parameters may need to be set to larger values in the sqlnet.ora file on the database server: SQLNET.INBOUND_CONNECT_TIMEOUT, SQLNET.SEND_TIMEOUT, and SQLNET.RECV_TIMEOUT
- Try to TNSPing (DESCRIPTION=(ADDRESS=(PORT=<port number> e.g. 1521)(HOST=<IP address> e.g. 10.20.30.40)(PROTOCOL=TCP))) using the TNS Ping button on the toolbar