sudo apt-get install vsftpd


vi /etc/vsftpd.conf
// Uncomment
write_enable=YES
local_umask=022
chroot_local_user=YES
// Add
allow_writeable_chroot=YES
pasv_enable=Yes
pasv_min_port=40000
pasv_max_port=40100
// End


sudo service vsftpd restart
sudo useradd -m ftpuser -d /var/www/html -s /usr/sbin/nologin
sudo passwd ftpuser

Continue for openssh encryption

sudo apt-get install openssh-server
sudo groupadd ftpaccess
vi /etc/ssh/sshd_config

// Comment
Subsystem sftp /usr/lib/openssh/sftp-server
// Add
Subsystem sftp internal-sftp
Match group ftpaccess
ChrootDirectory %h
X11Forwarding no
AllowTcpForwarding no
ForceCommand internal-sftp
// End

sudo service ssh restart
sudo useradd -m ftpuser -g ftpaccess -d /var/www/html -s /usr/sbin/nologin
sudo passwd ftpuser
sudo chown root /home/ftpuser
sudo chown -R ftpuser:ftpaccess /var/www/html