Geekido

After spending a week in IPv6 training, I decided to give it a whirl at home. My stuff is supposed to support it, so why not?  After a bit of futzing, I successfully configured my Airport Extreme Base Station (AEBS) to act as an IPv6 6to4 tunnel via a tunnel broker, and got my laptop taking IPv6 to the Internet.  Here’s what I did, and the gotchas I found.

What the heck is IPv6?

If you have to ask, you probably have no interest in this post. Really. But if you’ve just got to know, go see http://en.wikipedia.org/wiki/IPv6.

Equipment

Actiontek network supplied for Verizon for FIOS

Airport Extreme Base Station running 7.4.2 firmware

Time Capsule running 7.5.1 firmware.

Assorted Macs running OS X 10.6.3 (Snow Leopard)

Starting Network Configuration

The Actiontek router connects to the FIOS and has a public IPv4 address from Verizon. It NATS IPv4, and supplies addresses via DHCP to the rest of the home network. Wireless is off.

The AEBS bridges the network from the Actiontek, and started with a dynamic address on the WAN port. It serves up the wireless network to the house.

The Time Capsule extends the wireless network from the AEBS.

Most of the clients in the house connect via WiFi, but one host is directly connected to the AEBS.

Getting Started

After some Internet searching, I found a good tutorial that got me 90% of the way there. Niall’s AEBS was a little bit older than mine, and he has a Windows client, so I couldn’t mindlessly follow his instructions, though.

Step 1: Get a tunnel via a tunnel broker

First I went to Hurricane Electric and signed up for a free tunnel. This tunnel lets my IPv6 clients (actually dual-stacked clients talking IPv6) to tunnel to other IPv6 hosts using the IPv4 Internet. Once applied for the tunnel, I needed to configure the tunnel on the AEBS.

Step 2: Get your Routed /48 prefix

I found I did not actually need to have the tunnel working to get my Routed /48 prefix. It’s better to do this before setting up the AEBS, since it provides one of the parameters for the setup. Niall was a bit vague on how to get this allocation. Log into Hurricane Electric at http://www.tunnelbroker.net. On the main page when you log in, you should see your tunnel listed near the bottom of the page, with the tunnel name as a link to Tunnel Details. Click the link to get to the details. Near the bottom you’ll see “Routed 48:”, and then words to the effect of “Not Allocated”. These words are actually a link, and if you click on them, you’ll get your allocation.

Step 3: Configure Your AEBS

Niall’s directions were pretty good here, but the labels for the Advanced->IPv6 tab were different than his.  Here are the configuration options I had on the AEBS, and what I filled in.

IPv6 Mode: Tunnel

Block Incoming IPv6 Connections: Checked

Configure IPv6: Manually

Remote IPv4 Address: Server IPv4 address from Tunnel Details

WAN IPv6 Address: Client IPv6 address from Tunnel Details

IPv6 Default Route: Server IPv6 address from Tunnel Details

Lan IPv6 Address: Take the Routed /48 from the Tunnel Details, strip the /48 off the end and replace it with 1.

Step 4: Get a client set up, and test

On the laptop, I went to System Preferences->Network, then selected my interface (in my case Airport). I then clicked the “Advanced” button and picked the “TCP/IP” tab. I changed “Configure IPv6″ from “Off” to “Automatically”. It picked up an IPv6 router, address, and prefix length from the AEBS.

Then, as suggested by Niall, I went to http://www.whatismyipv6.net to test. It showed up with an IPv4 address, so my tunnel wasn’t up.

Step 5: Static addressing on the AEBS

In searches earlier in the day, I recalled reported problems with AEBS 7.4.2 establishing a tunnel when it’s WAN IPv4 IP was dynamic. I changed the pool on the Actiontek router, then set the AEBS address statically to the same address it had previously held dynamically. The AEBS did not start properly after this, though it had a green LED, so I had to power cycle it. It came up after the power cycle, but whatismyipv6 still showed my IPv4 address.

Step 6: Configure the Actiontek router to pass the tunnel traffic to the AEBS instead of filtering it

Rather than muck with custom firewall rules on the Actiontek, I opted to set the AEBS as a DMZ host.

I restarted the AEBS to make it establish the tunnel, and this time it worked! I was on the IPv6 Internet.

So, now I’m there, and I can’t find anything interesting. If I do, though, I’ll post it.