NETGEAR FVX538 - ProSafe VPN Firewall 200 Router Reference Manual page 205

ProSafe VPN Firewall 200 FVX538 Reference Manual
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, the previously inactive gateway WAN port becomes the
active port (port WAN2 in this example) and the remote PC must re-establish the VPN tunnel. The
gateway WAN port must act as the responder.
Figure B-19
The purpose of the fully-qualified domain name is this case is to toggle the domain name of the
gateway router 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.
Network Planning for Dual WAN Ports B-19
v1.0, March 2009