NETGEAR SRX5308 - ProSafe® Quad WAN Gigabit SSL VPN Firewall Reference Manual page 334

ProSafe Gigabit Quad WAN SSL VPN Firewall SRX5308 Reference Manual
Figure B-13
The IP address of the gateway WAN ports can be either fixed or dynamic. If an IP address is
dynamic, you must use an FQDN. If an IP address is fixed, an FQDN is optional.
VPN Gateway-to-Gateway: Dual Gateway WAN Ports for Improved Reliability
In a configuration with two dual WAN port VPN gateways that function in auto-rollover mode,
either of the gateway WAN ports at one end can initiate the VPN tunnel with the appropriate
gateway WAN port at the other end as necessary to balance the loads of the gateway WAN ports
because the IP addresses of the WAN ports are known in advance. In this example (see
Figure B-14), port WAN_A1 is active and port WAN_A2 is inactive at Gateway A; port WAN_B1
is active and port WAN_B2 is inactive at Gateway B.
Figure B-14
The IP addresses of the gateway WAN ports can be either fixed or dynamic, but you must always
use an FQDN because the active WAN ports could be either WAN_A1, WAN_A2, WAN_B1, or
WAN_B2 (that is, the IP address of the active WAN ports is not known in advance).
B-14 Network Planning for Multiple WAN Ports
v1.0, April 2010