Also, I was able to traceroute6 the path to ipv6.google.com, and others without issue. However, when I attempt to send data packets, there is a 100% loss.

Given the amount of details you have given, I would say that it does not work. Or otherwise stated: please actually SHOW the output of the various interface, routing, tunnel etc etc tables and provide outputs of traceroutes and everything else as requested by that big yellow/orange box. I am really wondering if we should let people click on "yes I saw this and I really really really understand it and will provide proper details" or something as lots of people seem to miss out on it. Do realize, that without data nobody can help you.

Hi, I'm using Pfsense 2.0RC, and gitsynched to the IPv6 branch a pair of weeks ago. You should keep always in mind what's been said in pfsense ipv6 forum: ipv6 support is 100% alpha and experimental at least until 2.1 release (and we're still in a RC phase for 2.0 so go figure...). Anyway the ipv6 branch works quite well.. Said that: he.net tunnels come up exactly as they should just by using the GUI. But SixXS tunnels doesn't. Why? I don't know (and I won't loose time with it). Just setup the tunnel in the GUI as described, and, finally, follow the guidelines given in the FAQ in this website, to setup the tunnel (specially the 2 regarding the local IPv6 endpoint and the default gw), and: gif0: flags=8051<UP,POINTOPOINT,RUNNING,MULTICAST> metric 0 mtu 1280 tunnel inet x.x.229.105 --> x.x.0.131 inet6 fe80::218:8bff:fe73:c97b%gif0 prefixlen 64 scopeid 0x9 inet6 2001:b18:2000:x::2 --> 2001:b18:2000:x::1 prefixlen 128 nd6 options=3<PERFORMNUD,ACCEPT_RTADV> options=1<ACCEPT_REV_ETHIP_VER> # ping6 -c1 2001:b18:2000:x::1 PING6(56=40+8+8 bytes) 2001:b18:2000:x::2 --> 2001:b18:2000:x::1 16 bytes from 2001:b18:2000:x::1, icmp_seq=0 hlim=64 time=11.887 ms # ping6 -c1 ipv6.google.com PING6(56=40+8+8 bytes) 2001:b18:2000:x::2 --> 2a00:1450:8002::93 16 bytes from 2a00:1450:8002::93, icmp_seq=0 hlim=55 time=45.694 ms It works :) I haven't been able to get both tunnels working at the same time (yet, as some users have reported being able to do it). Regards, Ruben.

m0n0wall works great with sixxs which is what pfsense was originally based on.