Port forwarding is a general case of a firewall rule, controlling inbound service requests from the Internet. In the FVS318v3, firewall rules are configured in the Rules menu.
To forward an inbound port to a local server, you must define an inbound services rule in the Rules menu:
1. Select Rules > Inbound Services and click Add. A submenu opens.
2. From the Services list, select the service whose port number (or port numbers) you wish to forward. If the service does not appear in the list, you must first define the service in the Services menu.
3. Select Action > Allow. You have the option to allow always or by the schedule defined in the Schedule menu.
4. For Send to LAN Server, type the IP address of your local server that will receive this traffic.
5. Under WAN Users, you have the option to restrict the Internet address range that is allowed to contact your local server.
6. Click Apply to save your rule and return to the Rules menu.
7. In the Rules menu, click Apply.
Considerations for using inbound rules:
- If your ISP assigns your external Internet IP address dynamically, the IP address may change periodically as the DHCP lease expires. Consider using the Dynamic DNS feature in the Advanced menus so that external users can always find your network.
- If the IP address of the local server PC is assigned by DHCP, it may change when the PC is rebooted. To avoid this, use the Reserved IP address feature in the LAN IP menu to keep the PC’s IP address constant.
- Each local PC must access the local server using the PC’s local LAN address. Attempts by local PCs to access the server using the external Internet IP address will fail.
- The order of the rules in the rules table is significant. For traffic trying to pass through the firewall, the packet information is subjected to the rules in the order shown in the Rules Table, beginning at the top and proceeding to the default rules at the bottom. In some cases the order of precedence of two or more rules may be important in determining the disposition of a packet. The Move button allows you to relocate a defined rule to a new position in the table.