INSTALL
sudo apt-get install pure-ftpd
sudo groupadd ftpgroup
sudo useradd -g ftpgroup -d /dev/null -s /etc ftpuser
sudo chown -R ftpuser:ftpgroup /var/ftpuser
Virtual Users
Administrator ftp
sudo pure-pw useradd $USERNAME -u ftpuser -d /home/ftpuser
sudo pure-pw mkdb
sudo pure-pw useradd $USERNAME -u ftpuser -d /home/ftpuser/someone -m
Setting Pure-FTPd to Start-up When the Server Restarts
cd /etc/pure-ftpd/conf
sudo echo 'no' > PAMAuthentication
sudo echo 'no' > UnixAuthentication
sudo echo '/etc/pure-ftpd/pureftpd.pdb' > PureDB
sudo ln -s ../conf/PureDB /etc/pure-ftpd/auth/50pure
Details
https://articlebin.michaelmilette.com/setting-up-pure-ftpd-in-ubuntu/