In this recipe, we will add a multi-WAN setup to our pfSense firewall. This recipe will generate a gateway group with two WAN interfaces, although it could easily be altered to cover gateway groups with more than two WAN interfaces.
Adding multiple WAN interfaces makes the most sense when we have more than one internet connection. If you are completing this recipe in order to understand the process of configuring multiple WANs, and you have both a broadband and mobile internet connection, you can use these as your two connections. Otherwise, you will want to acquire two internet connections, preferably from two separate ISPs (otherwise, if you acquire two connections from the same ISP, then both connections to the internet will likely go down if your ISP experiences problems—hardly the redundancy and high availability we seek). If you have no choice but to use a single ISP, it might be helpful to obtain connections with different types of cabling...