Connectivity between IPv6 Teredo host and IPv6 6to4 Host

Question

I have two computers.

Host 1 is a Debian machine running Miredo (Terido client) inside of a VirtualBox VPN. The VM host is running under a private IP address space (192.168.0.0).

Host 2 is an Ubuntu machine.

Host 1 <-> Virtual Host <-> Corporate NAT Gateway <-> Internet <-> D-Link 6to4 <-> Host 2

From host 1 I can ping6 ipv6.google.com From host 2 I can ping6 ipv6.google.com From host 1 to host 2 95% packets are dropped. May

However I am not able to ping between host 1 and host 2. I am getting 95% of the packets are being dropped. Interestingly a few are actually making it through but not enough to establish a reliable connection.

My questions ...

Is it possible to communicate between an IPv6 6to4 host and a IPv6 Teredo host?

UPDATE: I have managed to get a traceroute to between the machines while it was working ...

 1  6to4.fmt2.he.net (2001:470:0:108::2)  102.245 ms  102.240 ms  102.244 ms
 2  gige-g5-20.core1.fmt2.he.net (2001:470:0:108::1)  102.487 ms  102.387 ms  102.267 ms
 3  10gigabitethernet1-2.core1.pao1.he.net (2001:470:0:30::2)  365.425 ms  365.299 ms  365.180 ms
 4  6to4.pao1.he.net (2001:470:0:13b::2)  369.045 ms  367.008 ms  366.802 ms
 5  2002:ae00:444a::ae00:444a (2002:ae00:444a::ae00:444a)  164.187 ms  167.457 ms  172.094 ms
 6  2002:ae00:444a:5:215:f2ff:fe5c:2a16 (2002:ae00:444a:5:215:f2ff:fe5c:2a16)  171.991 ms * *

It jumps between working, 75% packet failures and just plain old destination unreachable.

Answer 1

It should work, but is dependent on correctly functioning relay routers run by third parties.

To simplify debugging it makes sense to test Teredo and 6to4 seperately. I used Hurricane Electric's looking glass to ping your D-Link router from the routers listed 2 and 3 in your traceroute output, IPv4 worked, IPv6 lost lots of packets. I can ping myself from there OK.

I can ping your D-Link via a direct 6to4 tunnel without problems, but if I direct replies via Hurricane Electric, by using a source address delegated from them packets go missing. It would appear the path from your D-Link to Hurricane Electric id faulty, so using traceroute from to 6to4 end will help finding the problem. Also try traceroute to 192.88.99.1, the 6to4 relay anycast address.

You should consider signing up with a tunnelbroker, to avoid the problems broken with 6to4 relay routers.