To add the FTP plugin module in a service object: The FTP plugin module indicates that no Port Address Translation (PAT) is performed for FTP data sessions, even if the firewall session is NAT'd. After an initiating request on port 21, the server answers with port 24500. The following diagram illustrates how data is transferred in an FTP session that is established through the Barracuda CloudGen Firewall with the FTP plugin module. With the FTP plugin module, the Barracuda CloudGen Firewall listens to the two FTP partners and opens the chosen port for the connection. Active FTP sessions use port 21 to establish connections, and then the client and the server use a port from 1024 through 65535 to send and receive data. Because an active FTP session transfers data over a randomly chosen port, apply the FTP plugin module to your service objects to ensure that only the chosen port is opened for these types of connections.
