Network DBA
This link contains common network issues for Oracle Connectivity along with brief description of network files.
1. LISTENER.ORA file
It is a server side file and contains information regarding network configuration parameters. It can be found in the ORACLE_HOME/network/admin directory on the server.
Sample File
SID_LIST_LISTENER = LISTENER = |
If listener is modified then the listener should be restarted or reloaded to allow the new configuration to take place. Basic commands of Listener control utility are as follows:
LSNRCTL>start LSNRCTL>stop LSNRCTL>reload LSNRCTL>status LSNRCTL>show
2.TNSNAMES.ORA file
It is a Client side file which is created on both sites SERVER/CLIENT. It contains client side network configuration parameters.It can be found in the ORACLE_HOME/network/admin. It can be found on the server if client style connections are used on the server side.
ORCL = |
3. SQLNET.ORA file
It is a Client side file which is created on both sites SERVER/CLIENT. It is use for user AUTHENTICATION purpose.
SQLNET.AUTHENTICATION_SERVICES= (NTS) |
Another good link for commonly known TNS errors from