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Stuart · 03-08-2004, 14:49

Once you have ensured Port 21 is open at your firewall (I know you probably have, I just want to check), you may need to connect your FTP clients using passive connections (there should be an option in the program to do this).

Normally FTP uses active connections. What this means is that the FTP server will recieve a request to connect on port 21. Once it has found out the IP of the connection computer, it drops the connection and opens one on a random port. If it can't establish a connection on a random port, you won't be able to get in. It can be a bitch to configure firewalls to allow active connections.

If the FTP client requests a Passive connection, the ftp server will happily talk to it on port 21.

03-08-2004, 14:49	#2
Stuart - Join Date: Jun 2003 Location: Somewhere Services: Virgin for TV and Internet, BT for phone Posts: 26,546	Re: FileZilla (server) Once you have ensured Port 21 is open at your firewall (I know you probably have, I just want to check), you may need to connect your FTP clients using passive connections (there should be an option in the program to do this). Normally FTP uses active connections. What this means is that the FTP server will recieve a request to connect on port 21. Once it has found out the IP of the connection computer, it drops the connection and opens one on a random port. If it can't establish a connection on a random port, you won't be able to get in. It can be a bitch to configure firewalls to allow active connections. If the FTP client requests a Passive connection, the ftp server will happily talk to it on port 21.