You have just turned on your FTP server. If you looked at the ftp entry in your /etc/inetd.conf file, you noticed that the server runs by default with the -l option, which is the option that forces the logging of successful and unsuccessful FTP sessions.
Many other options are available in the FTP server, and they are detailed in the command documentation table, Table 25.1. To implement any of the options, edit the ftp entry in the /etc/inetd.conf file. Remember to back up /etc/inetd.conf before making any changes.