To make sure your network is always connected to the Internet you can engage the services of two or more Internet service providers and set up redundant Internet connections. Then, if one of your ISPs service is interrupted, all of your Internet traffic can be switched to the other ISP, maintaining your Internet connection. Also, while both ISPs are operating you can load balance traffic between them, increasing your network’s available Internet bandwidth.

Previous versions of FortiOS required a few steps to set up two interfaces as redundant Internet connections. The setup also involved some special routing and load balancing setup and creating duplicate policy configurations for each Internet facing interface. In addition, previous versions of FortiOS supported basic link monitoring.

FortiOS 5.2 adds a new type of interface called a virtual WAN link. A virtual WAN link consists of two or more physical interfaces that are connected to two or more ISPs and to the Internet as well as the load balancing and routing configuration required to support redundant internet connections. In addition, the virtual WAN link configuration also includes new link health checking and settings to control traffic flow based on link health.

The FortiGate unit sees the virtual WAN link as a single interface so the FortiGate’s security policy configuration no longer has be redundant to support dual Internet links. Now one policy configuration to control traffic to the virtual WAN link is all that is required. You can also add or remove redundant Internet links just by adding or removing physical interfaces from the virtual WAN link. No addition changes to the routing, load balancing or firewall policy configuration are required.