To Configure VSFTP log format, Open the configuration file
# vi /etc/vsftpd/vsftpd.conf
Disable the standard ftpd xferlog log format:
xferlog_std_format=NO
Enable the verbose vsftpd log format. The default vsftpd log file is /var/log/vsftpd.log:
log_ftp_protocol=YES
vsftpd_log_file=/var/log/vsftpd.log
Append the below line to enable dual log
dual_log_enable=YES
That’s it.