IPv6 Support on Comcast using OpenWrt

I’ve recently moved to an area covered by Comcast’s IPv6 Network, and I was surprised to learn how difficult it was to get my aging router working with Comcast’s IPv6 Implementation.

I had an old Buffalo WZR-HP-G300NH and a newer TP-Link TL-WDR3600 lying around, but I had trouble getting either to pull IPv6 addresses on Comcast with my trusty Mortotola SB6121, though my laptop connected directly worked just fine.

The Buffalo router has an official DD-WRT build for it which ostensibly supports IPv6, and the TP-Link Official documentation also claims IPv6 support although neither worked for me, even with firmware updates.

I’ve loved using DD-WRT in the past, but its countless versions, or “builds” are extremely confusing. This article tries to somewhat clarify their release system. For starters, you have to search their outdated database for which build to use on each router, but look around in the forums and most people agree that these recommendations are typically outdated or wrong. Unlike OpenWRT, there are no “stable releases” so which version to use can be very confusing.

After doing some digging I decided to give OpenWRT a try. OpenWRT is a Linux based firewall distribution, which supports a large quantity of commercial home routers. It’s a full baked Linux distro – offering Web Management Interface, A simple configuration system, and is extremely versatile due to the large amount of packages available via its package manager, opkg. Best of all, it supported IPv6 right out of the box!


I installed the current stable release, Chaos Calmer 15.05, on both routers. The install was easy – The TP-Link was updated directly from the official firmware and I updated my Buffalo from DD-WRT from the command line.

The default LuCi Web interface is simple but intuitive. All the typical configuration options exist, such as port forwarding, static DHCP reservations, and wifi configuration (Hint: wifi is off by default).


Many more settings can be configured via simple configuration files, just enable the ssh server and fire up your editor of choice to make changes to the configuration files under /etc/config.


The real beauty was how easy it was to add functionality in OpenWRT –  I wanted to set up a dynamic DNS agent and enable some statistics collection. No problem – just install a package via opkg and you’ll be set up in minutes.

How about setting up remote access via OpenVPN? Or installing a torrent client so you can download all of your favorite torrents? All this and more is possible via the huge package repository and great documentation.

I came to OpenWRT for the IPv6 support and I’ve really impressed with it so far. Hopefully it will work for you as well!