Configure BGP

BGP enables learning dynamic routes from the datacenter. The BGP configuration is normal, with the definition of the datacenter FortiGate tunnel IP addresses set as BGP peers.

Routes that have the same network mask, administrative distance, priority, and AS length are automatically considered for SD-WAN when the interfaces that those routes are on are added to the SD-WAN interface group.

In order to facilitate the fastest route failovers, configure the following timers to their lowest levels: scan-time, advertisement-interval, keep-alive-timer, and holdtime-timer.

The distance-external option might need to be configured if you need routes that are learned from BGP to take precedence over static routes.

To configure BGP on the branch FortiGate:

config router bgp
    set as 65501
    set router-id 10.254.0.2
    set ebgp-multipath enable
    config neighbor
        edit "10.254.0.1"
            set soft-reconfiguration enable
            set remote-as 65500
        next
        edit "10.254.1.1"
            set soft-reconfiguration enable
            set remote-as 65500
        next
    end
end