In Datafari, the logs are not automatically purged. To do this, you need to edit the root crontab with the command 'sudo crontab -e', and add the following line:
0 1 * * * find /opt/datafari/logs/ -type f -mtime +7 | xargs --no-run-if-empty rm
This will remove the logs older than the last 7 days. You can adjust the value to fit your needs.