I have a working tunnel but trying to use the sixxs recursive dns servers is failing. Is it possible they don't recognize me as coming from within sixxs address space? # ip addr show sixxs 78: sixxs: <POINTOPOINT,NOARP,UP,LOWER_UP> mtu 1280 qdisc noqueue state UNKNOWN link/sit 87.198.231.90 peer 212.126.37.76 inet6 2a00:15b8:100:7::2/64 scope global valid_lft forever preferred_lft forever inet6 fe80::57c6:e75a/64 scope link valid_lft forever preferred_lft forever # ping6 nscache.eu.sixxs.net PING nscache.eu.sixxs.net(chzrh01.sixxs.net) 56 data bytes 64 bytes from chzrh01.sixxs.net: icmp_seq=1 ttl=55 time=52.2 ms 64 bytes from chzrh01.sixxs.net: icmp_seq=2 ttl=55 time=52.5 ms ^C --- nscache.eu.sixxs.net ping statistics --- 2 packets transmitted, 2 received, 0% packet loss, time 1001ms rtt min/avg/max/mdev = 52.207/52.371/52.536/0.281 ms # ping6 -n nscache.eu.sixxs.net PING nscache.eu.sixxs.net(2001:41e0:ff00::5) 56 data bytes 64 bytes from 2001:41e0:ff00::5: icmp_seq=1 ttl=55 time=52.1 ms ^C --- nscache.eu.sixxs.net ping statistics --- 1 packets transmitted, 1 received, 0% packet loss, time 0ms rtt min/avg/max/mdev = 52.116/52.116/52.116/0.000 ms # dig @2001:41e0:ff00::5 www.google.com ; <<>> DiG 9.7.0-P1 <<>> @2001:41e0:ff00::5 www.google.com ; (1 server found) ;; global options: +cmd ;; connection timed out; no servers could be reached