Oracle notes

Basic software architecture:

Oracle client -- Oracle net <--- network ---> Oracle net -- Oracle Server

• Client connection 'connect identifier' (resolves connect description from tnsnames.ora and connects);
• Server listener brokers the connect request and sends it to the database (listener is listening for connection defined in listener.ora only)
  

Listener command:

# lsnrctl [ start | stop | status ]

Server listner configuration file:

$ORACLE_HOME/network/admin/listener.ora

Client configuration file:

$ORACLE_HOME/network/admin/tnsnames.ora