red lion remote ftp trouble

Good day everyone. I'm having problems with using the FTP server on a Graphite HMI. I am using CoreFTP as my client. It works succesfully when connected over the LAN. When I try to use it remotely via port forwarding the session log shows the connection is established and accepts the USER and PASS but it cannot retrieve the data. I have tried disabling the tls but no change.



My webserver and program download work properly. Any suggestions?

which ports are forwarded? port 20 (IIRC) is sometimes used for data transfer, but I am not sure it needs to be forwarded. It has something to do with active vs. passive transfers.


You might try asking The Google about FTP servers behind NAT routers.