Dual internet connections

Dual internet connections, also referred to as dual WAN or redundant internet connections, refers to using two FortiGate interfaces to connect to the Internet. This is generally accomplished with SD-WAN, but this legacy solution provides the means to configure dual WAN without using SD-WAN. You can use dual internet connections in several ways:

  • Link redundancy: If one interface goes down, the second interface automatically becomes the main connection.
  • Load sharing: This ensures better throughput.
  • Use a combination of link redundancy and load sharing.

This section describes the following dual internet connection scenarios:

Scenario 1: Link redundancy and no load-sharing

Link redundancy ensures that if your Internet access is no longer available through a certain port, the FortiGate uses an alternate port to connect to the Internet.

In this scenario, two interfaces, WAN1 and WAN2, are connected to the Internet using two different ISPs. WAN1 is the primary connection. In the event of a failure of WAN1, WAN2 automatically becomes the connection to the Internet. For this configuration to function correctly, you must configure the following settings: