Oracle database listener is the TCP/IP communication protocol that end-connections from different sources (Applications, Services, Client Apps….etc) use to connect to the back-end Oracle database system.
The listener logs every authentication taking place in a listener log file (XML, and TEXT) formats. The listener log text format accumulates in size over time and with the growth of the size of this file this…..it might impact your database authentication performance. In addition, Listener log file is a good source for “forensic” investigation . So, it must be retained some time based on your internal policies and needs.
How to rotate your listener log file ?
Add the following 2 parameters in your listener.ora file ( located traditional in the following path $ORACLE_HOME/network/admin )
Reference Documentation for further insights:
Its worth stating that database listener will not rotate automatically….A listener restart is required (not reload).