What port numbers are used for data connections in passive mode in FileZilla Server? Can I limit them to a smaller range?

By default, when a client is asking for a data connection in passive mode, FileZilla Server will pickup an available port higher than 1024, and use it to listen to connection requests from the client.

If your FileZilla Server is protected by a firewall, you may want to limit the available port numbers to a smaller range. This helps to make the system more secure, because you only need to open port numbers in that smaller range on the firewall.

For example, if you limit available port numbers to 9001 to 9010 for data connection in passive mode in FileZilla Server, you only need to open 10 ports (from 9001 to 9010) on the firewall. Other ports can be closed.

Here are the steps to change the port number range for data connections in passive mode in File on FileZilla Server:

1. Start the FileZilla Server and Start the FileZilla Server Interface.

2. Click "Edit > Settings" menu on FileZilla Server Interface. You see FileZilla Server Options screen showing up.

3. Click "Passive mode settings" from the list on the left. You see Passive Mode Settings showing up.

4. Check the "Use custom port range" checkbox. And enter "9001 - 9010" as the port number range.

5. Click "OK" to save the change.

Now, the FileZilla Server will use a port number in the 9001 and 9010 range for data connection in passive mode, if a client asks for it.

⇒ "Failed to retrieve directory listing" on FileZilla Server

⇐ Find and Read Log File on FileZilla Server

⇑ Managing FileZilla Server

⇑⇑ FTP - Frequently Asked Questions