This article explains how to redirect FTP traffic to a server on LAN. To redirect the FTP traffic to an internal server, it requires 1. Changing the router's FTP service port 2. Setting up NAT to forward traffic on port 21 to the internal server. Vigor Router supports FTP ALG (Application Layer Gateway), after open the FTP command port (TCP 21), the router will inspect the command packets to learn which port the FTP client will use for data transmitting, and then open the data port accordingly. However, the FTP ALG of Vigor Router only inspects the packets transferred on port 21, if the FTP server on LAN uses other command port, FTP ALG will not work, and transmitting data in passive mode may fail.
1. Go to System Maintenance >> Management >> Management Port Setup, change the FTP Port to any other not used port.
2, Go to NAT >> Open Ports, and edit a profile as follows:
1. Go to System Maintenance >> Access Control, at Management Port Setup, change the FTP Port to an used port.
2. Go to NAT >> Port Redirection to add a profile as follows: