In this chapter, we discussed pfSense's multi-WAN capabilities, a continuation of our discussion of redundancy and high availability from the previous chapter. A multi-WAN setup with multiple internet connections enables us to achieve a level of reliability and bandwidth that would not be possible with a single connection. Moreover, pfSense makes it easy for us to switch between link aggregation/load balancing and failover. Setting up a multi-WAN gateway group entails several steps. In addition to creating the gateway groups, we must also configure DNS settings, create firewall rules to direct traffic to the gateway, and, if necessary, create NAT rules. In addition, special use cases may require additional steps; we covered one such use case (a multi-WAN setup with a CARP failover group).

In the next chapter, we will cover two basic concepts that you might not encounter in the typical home or small office/home office deployment, but become important in corporate deployments: routing and bridging, including a discussion of both static routing and dynamic routing via such protocols as the Routing Information Protocol (RIP) and the Border Gateway Protocol (BGP).