NETGEAR UTM5EW-100NAS, STM150EW-100NAS manual 634

ProSecure Unified Threat Management (UTM) Appliance

Figure 371.

The IP addresses of the gateway WAN ports can be either fixed or dynamic, but you always need to 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).

After a rollover of a gateway WAN port, the previously inactive gateway WAN port becomes the active port (port WAN_A2 in the following figure), and one of the gateways needs to reestablish the VPN tunnel.

Figure 372.

The purpose of the FQDNs is to toggle the domain name of the rolled-over gateway between the IP addresses of the active WAN port (that is, WAN_A1 and WAN_A2 in the previous figure) so that the other end of the tunnel has a known gateway IP address to establish or reestablish a VPN tunnel.

VPN Gateway-to-Gateway: Dual-Gateway WAN Ports for Load Balancing

In a configuration with two dual WAN port VPN gateways that function in load balancing mode, either of the gateway WAN ports at one end can be programmed in advance to initiate the VPN tunnel with the appropriate gateway WAN port at the other end as necessary to manage the loads of the gateway WAN ports because the IP addresses of the WAN ports are known in advance.

Network Planning for Dual WAN Ports (Multiple WAN Port Models Only)

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