Note: Advanced configuration for users running NAT or Firewall devices.
If you are using CuteFTP Server behind a firewall or NAT device, you may need to specify the Server's IP address or range of ports that it will pick from when issuing IP:PORT information to clients.
Start the Administrator Interface.
At the bottom of the left pane, click the Server tab.
In the left pane, select the Site.
In the right window, click the Site Options tab.
Select the Assign PASV mode IP Address check box.
In the IP box, enter the server's IP address as should be seen by those outside your network.
Note: Usually applies under SSL sessions (not supported by CuteFTP Server home) when the NAT or FW device can't see and therefore properly map the internal IP address of the server. Also applies if the NAT or FW device is misconfigured. It is recommend you first try connecting to the server with this field left as is.
In the Port Range boxes, enter the range of ports the server will use for PASV connections.
Note: User primarily to limit the amount of ports used for the data connection portion of the FTP session, especially when the FW or NAT device was configured to only allow traffic on certain ports.
Click the Apply button.
Note
If you specify a PASV mode port range you must be sure to open the same range of ports on your firewall.
3rd Party Links
An excellent primer on PASV vs. PORT mode.
Related Topics
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