ProSafe Dual WAN Gigabit Firewall with SSL & IPsec VPN FVS336G Reference Manual
Network Planning for Dual WAN Ports C-13
v1.2, June 2008
The IP addresses of the gateway WAN ports can be either fixed or dynamic, but a fully-qualified
domain name must always be used because the active WAN port could be either WAN1 or WAN2
(i.e., the IP address of the active WAN port is not known in advance).
After a rollover of the gateway WAN port (FigureC-11), the previously inactive gateway WAN
port becomes the active port (port WAN2 in this example) and the remote PC client must re-
establish the VPN tunnel. The gateway WAN port must act as the responder.
The purpose of the fully-qualified domain name in this case is to toggle the domain name of the
gateway firewall between the IP addresses of the active WAN port (i.e., WAN1 and WAN2) so that
the remote PC client can determine the gateway IP address to establish or re-establish a VPN
tunnel.
VPN Road Warrior: Dual Gateway WAN Ports for Load Balancing
In the case of the dual WAN ports on the gateway VPN firewall (FigureC-12), the remote PC
initiates the VPN tunnel with the appropriate gateway WAN port (i.e., port WAN1 or WAN2 as
necessary to balance the loads of the two gateway WAN ports) because the IP address of the
remote PC is not known in advance. The chosen gateway WAN port must act as the responder.
Figure C-11