With 11g Release 1 Oracle introduced the Automatic Diagnostic Repository – “ADR”. The ADR is designed as central repository for storing all oracle-related log files such as alert.log, listener.log and so on.
The log files are stored in XML format and in a subdirectory called “trace” in the pre-11g format.
By default the ADR-Home is located in $ORACLE_BASE. The path can be changed in the database by changing the parameter DIAGNOSTIC_DEST.
For the listener this change does not work. If you want to change the location the listener places its log files add the following parameter to the LISTENER.ORA file to change the path to the ADR:
ADR_BASE_listener = <path>
“listener” is the name of the listener to be changed. If your listener is named differently the parameter must be changed as well!