Force Server IP for PASV mode

Can someone tell me in detail EXACTLY what this option does if the FTP server already is operating in passive mode? What effect does this have if the connection type is set to passive mode instead of default? What effect does it have if the server only responds to passive command?


I ask because I have 2 servers on my LAN and have them listening on different ports in order to separate the incoming requests for them (since a connection inbounds has the same WAN IP or host name). For one, it's allowing active right now, but using SmartFTP I can only get the data port NOT to time out if I select to connect in passive mode and check the option to force the server IP for passive mode.

I was just hoping someone could explain this effect in SmartFTP a bit.


thanks,


Chip