3.5.2 Connection

The most common cause of connection problems are:

• The database user id or password is wrong. This can usually be diagnosed by looking in the x_err.log where the X_RUN parameters are listed.
• The ORACLE listener or database is not started. To check whether the listener is started use the following command on the database server

    lsnrctl status

To see whether the database is started use the following command on the database server

    ps -ef | grep $ORACLE_SID

• The ORACLE listener is not configured correctly. Refer to Oracle support and manuals for possible causes.