参考原始：
How to Disable Logging to the Sqlnet.log and the Listener.log (Doc ID 162675.1)
适用于：
Oracle Net Services
Information in this document applies to any platform.
Checked for relevance on 15-Jan-2012
解决方式：
Disable Client / Server logging
To disable Oracle Net logging to the sqlnet.log file, add the following parameters
and values to the SQLNET.ORA file:
Unix: LOG_DIRECTORY_CLIENT = /dev/null OR LOG_FILE_CLIENT = /dev/null
Windows: LOG_DIRECTORY_CLIENT = NULL
Default location of the net admin files is ORACLE_HOME/network/admin
Any process already running will continue to log to the sqlnet.log file, untill it is restarted.
Disable Listener Logging
Method 1.
In order to disable logging without stopping the listener, using the LSNRCTL command as follows:
LSNRCTL>set current_listener <listener_name> (if not using default LISTENER)
LSNRCTL>set LOG_STATUS off
LSNRCTL>save_config
If you‘re trying to disable listener logging temporarily, do not issue SAVE_CONFIG.
Once listener logging is disabled, you can now safely delete or archive the existing listener log.
To restore logging again and/or to create a new listener log, simply enable logging as follows:
LSNRCTL>set current_listener <listener_name> (if not using default LISTENER)
LSNRCTL>set LOG_STATUS on
Method 2.
You can also edit the LISTENER.ORA file and set LOGGING_<listener_name> to OFF LOGGING_<listener_name>=OFF
This requires that a lsnrctl reload or restart take place in order to pick up the changes.
Listener.ora file location can be found with command lsnrctl status, showing the file is use by the listener.
Warning! Disabling Oracle Net logging is not recommended and should only be used under particular circumstances and/or under instruction by Oracle Support.
