high packet loss without exposed host

[fus2000]

I tried using a tunnel to a local Banana Pi running Lubuntu 14.04. The Banana Pi is connected to a DSL router (Vodafone EasyBox 802 with newest firmware 20.02.235) which gets dynamic IP addresses. Currently I have set the correct address manually, but this is only for testing purposes to reduce the number of possible failures.

When I run "traceroute6 -w 2 -q 10 ipv6.google.com" (results see bolow) or ping6 I see quite a high number of packet losses and the connection does not seem to work reliably. If I configure the Banana Pi as exposed host ("DMZ") in the router everything seems to work correctly, but I don't want to use that configuration.

Other settings in my router are only port forwarding for UDP or TCP ports and I could not find any information if it supports protocol 41.

Is there anything else I can do or do I need another tunnel broker which supports AYIA (e.g.) to use a UDP port which should work over NAT?




Her is the output of traceroute:

traceroute to ipv6.l.google.com (2a00:1450:400c:c00::8b) from 2001:470:1f0a:3a7::2, 30 hops max, 16 byte packets
1  * xxxxxx.tunnel.tserv6.fra1.ipv6.he.net (2001:xxxx:yyyy:zzz::1)  15.89 ms * * *  16.72 ms  16.841 ms  16.618 ms  15.581 ms  16.962 ms
2  v399.core1.fra1.he.net (2001:470:0:69::1)  12.192 ms * * * * * * * * *
3  de-cix10.net.google.com (2001:7f8::3b41:0:1)  99.107 ms *  89.301 ms  74.023 ms  73.418 ms * * * *  81.646 ms
4  2001:4860::1:0:4ca2 (2001:4860::1:0:4ca2)  15.582 ms *  64.564 ms  37.789 ms * *  12.58 ms  16.157 ms  15.948 ms  15.403 ms
5  2001:4860::8:0:5038 (2001:4860::8:0:5038)  11.749 ms *  13.647 ms  14.667 ms  22.378 ms  15.71 ms *  52.198 ms  31.08 ms  23.629 ms
6  2001:4860::8:0:8f8e (2001:4860::8:0:8f8e)  15.872 ms * *  16.028 ms  17.06 ms  15.42 ms *  15.348 ms  15.393 ms  16.925 ms
7  2001:4860::8:0:507b (2001:4860::8:0:507b)  26.749 ms *  26.215 ms  26.418 ms  26.438 ms  25.569 ms  26.021 ms  37.17 ms  27.359 ms  1461.04 ms
8  2001:4860::2:0:76e8 (2001:4860::2:0:76e8)  56.733 ms  33.021 ms  26.149 ms  25.701 ms  25.96 ms  26.714 ms  26.25 ms  25.993 ms  26.8 ms  26.259 ms
9  * * * * * * * * * *
10  wg-in-x8b.1e100.net (2a00:1450:400c:c00::8b)  24.32 ms * * * * * * *  24.56 ms  24.416 ms