Red Lion Flexedge with FTP server/PLC

[logic-man]

We are using Red Lion DA70s with Crimson 3.2. They are setup as cellular and a router. We have port forwarding rules and whitelisting. All of our rules work properly except forwarding ports to our PLC controllers for FTP. We used Cradlepoint routers previously and we could get to our 8 PLC's FTP behind the Cradlepoint when the application layer was checked for FTP. Does anyone have any experience with this or any insight as to why we cant get it working with Red Lion?

 

[drbitboy]

The FTP protocol sometimes uses Port 20, if I remember correctly; also that might be UDP, although if the connect is initiated from the server, then it should not need to be forward, but it would need to be whitelisted.

Also, some FTP clients can tell the server to use passive mode i.e. to not use Port 20.

Yeah, here it is: see this link; and Port 20 is not UDP.

I don't know if that is your current problem, but it is a possibility.