Question: vsftpd how to enable sftp?
Answer: Install and Configure VSFTPD / SFTP on CentOS 7. ... 
Now that the vsftpd application is installed; edit configuration file /etc/vsftpd/vsftpd.conf and set the following settings as follows. ... 
Now add the following to the same file mentioned above. ... 
Save and exit the file. ... 
Restart the vsftpd service.