Turn on logging and tracing for Network Services

This lesson explores the steps required to turn on logging and tracing for Net8. To enable tracing you may change the listener.ora and sqlnet.ora files or you can use the Enterprise Manager component control utilities. You will begin by identifying the parameters and then show the different ways to control the levels of tracing and the locations of the trace files. The purpose of Oracle Net tracing and logging is to provide detailed information to track and diagnose Oracle Net problems such as connectivity issues, abnormal disconnection and connection delay. Tracing provides varying degrees of information that describe connection-specific internal operations during Oracle Net usage. Logging reports summary, status and error messages.

You can control the name of the trace file for each component. Any valid string can be used as a trace filename. You can control the destination directory of the trace file for sqlnet.ora and listener.ora through the Oracle Network Manager or you can edit the file directly to change the default trace file directory.

1. Server: The server-side trace files for Net8 are located by default in the $ORACLE_HOME/network/trace directory. You can change this default by changing the listener.ora parameter trace_directory_listener. For example, to direct all listener trace files to the /tmp/listener directory, enter trace_directory_listener=/tmp/listener
2. Client: Unfortunately, there is no default directory name specified for SQL*Net client logs, and many WINDOWS clients will have sqlnet.log files in many locations. To change the directory location, change the sqlnet.ora parameter called trace_directory_client. For example, to direct all client traces to c:\temp\oracle, enter trace_directory_client=c:\temp\oracle. To set tracing parameters using sqlnet.ora files, specify the following parameters in your sqlnet.ora file:

trace_level_client=user

trace_directory_client=/tmp/user

To activate tracing for the listener you can enter the

lsnrctl trace

command without changing the listener.ora file or re-loading your listener process. Otherwise, if you modified the sqlnet.ora or listener.ora files while the application was running, you must wait until you can start or restart the application to enable the changed parameters.
Normally, when a new trace file is created for a client, it overwrites any existing trace file for that component. If you want to save an existing trace file, you must change its name before running the trace facility again. However, if the trace_unique_client parameter is set to ON, the trace facility appends a process identifier to the name of each trace file generated so that several files can co-exist in the directory. Remember, there are alternatives to editing the parameter files. In Oracle Network Manager you can set the listener trace level, and non-default name and location for the trace file in the listener.ora file. To turn tracing on and off, use the TRACE command of the Listener Control Utility.
The next lesson discusses how to enable tracing for Oracle Network Services.