sftp_config

<Default>
        GlobalDownload          5m     #total speed download for all clients
        GlobalUpload            0       #total speed download for all clients (0 for unlimited)
        Download                0      #limit speed download for each connection
        Upload                  0       #unlimit speed upload for each connection
        StayAtHome              true    #limit client to his home
        VirtualChroot           true    #fake a chroot to the home account
        LimitConnection         50      #max connection for the server sftp
        LimitConnectionByUser   20       #max connection for the account
        LimitConnectionByIP     20       #max connection by ip for the account
        Home                    /home/$USER     #overrite home of the user but if you want you can use
        IdleTimeOut             5m      #(in second) deconnect client is idle too long time
        ResolveIP               true    #resolve ip to dns                         
        HideNoAccess            true    #Hide file/directory which user has no access
        DefaultRights           0640 0750       #Set default rights for new file and new directory
        ShowLinksAsLinks        false   #show links as their destinations
        ConnectionMaxLife       1d      #limits connection lifetime to 1 day
        ForceUser       www-data
        ForceGroup      www-data
        Home    /DATA/
</Default>

<User medieval>
        ForceUser       www-data
        ForceGroup      www-data
        Home    /
</User>