For FreeBSD 6.x/7.x, here are the relevant rc.conf variables; gifX is the gif interface to use for the tunnel, e.g. gif0, and $ipv4a, $ipv4b, $ipv6b have the same meaning as in broquea's post:
Also, make sure that the variables $gif_interfaces and $ipv6_network_interfaces contain gifX (see below).
- gif1 is the tunnel interface to use (you can pick any unused number instead of 1 though).
- Our IPv4 address is 126.96.36.199.
- The tunnel broker is at 188.8.131.52.
- We have been allocated 2001:470:1f04:143::2 as the IPv6 endpoint address.