This is one area that was a challenge for me on my attempts at passing the ROUTE exam. You can see on this site about my experience with setting up a Tunnel Broker connection to the folks at Hurricane Electric. I was caught off guard when I saw references to an “automatic” mode for the 6to4 tunnel. In all of my reading, I never saw a reference to this. I spent some time today and found several references that helped explain this mode. Although I don’t expect to get any questions on this specific configuration, it helps me understand how this works. This is something that I would have thought would have been covered in the Cisco CCNP Route/Switch student materials.
I have come across some of Keith Barker’s YouTube video’s. Not only does he do a great job on explaining how to setup the automatic 6to4 tunnel but came out with a secondary video on running dynamic routing protocols over the tunnel. Both of these are good to watch and keep on my reference list. I have watched these once already and plan on watching them several more times to get a firm handle on everything that Keith talks about.
Keith Barker – Automatic 6to4 Tunnel configuration
Keith Barker – Dynamic Routing with IPv6 6to4 Tunnels