vi /etc/ssh/sshd_config
# Subsystem sftp /usr/libexec/openssh/sftp-server
Subsystem sftp /usr/libexec/openssh/sftp-server -l VERBOSE -f LOCAL3
vi /etc/rsyslog.conf
local3.* /var/log/sftpd.log
systemctl restart rsyslog.service
systemctl restart sshd.service