Chapter 11 IPsec VPN for FortiOS 5.0 : IPv6 IPsec VPNs : Site-to-site IPv4 over IPv6 VPN example : Configure FortiGate A routing
  
Configure FortiGate A routing
This simple example requires just two static routes. Traffic to the protected network behind FortiGate B is routed via the virtual IPsec interface toB using an IPv4 static route. A default route sends all IPv6 traffic, including the IPv6 IPsec packets, out on port2.
config router static6
edit 1
set device port2
set dst 0::/0
next
edit 2
set device toB
set dst 192.168.3.0/24
end