Router Configuration for FTP server
If your server is behind a router, redirect the ports : ftp 21 from the router to the local ip of the ftp server. Set port redirection on the router for ports 80 and 21 to the server's local IP Address.
Go to Router configuration setup(for our server it is http://192.168.1.1).Then go to NAT(Network Address Translation)->NAT options->NAT Rule Entry->Add.Type the rule id,local address from and to,Destination port from and to and Local port.Local address is the server's IP(192.168.0.8 ) , destination port and local port is the default port for FTP(21).
After setting these configuration click commit and then click reboot.
Now the router configuration is changed for FTP server.