Our static tunnel haven't been working for 2 days. The configuration hasn't changed for over a month, in particular firewall/routing settings of both IPv4 and IPv6. NIC handle: MH8732-RIPE Tunnel: T63217 OS is Debian Squeeze. root:~# uname -a Linux fw1 2.6.32-5-686 #1 SMP Wed Jan 12 04:01:41 UTC 2011 i686 GNU/Linux root:~# ping6 2001:808:100:27::1 PING 2001:808:100:27::1(2001:808:100:27::1) 56 data bytes From 2001:808:100:27::2 icmp_seq=1 Destination unreachable: Address unreachable From 2001:808:100:27::2 icmp_seq=2 Destination unreachable: Address unreachable ^C --- 2001:808:100:27::1 ping statistics --- 2 packets transmitted, 0 received, +2 errors, 100% packet loss, time 1007ms root:~# tcpdump -n -i eth0 -s 1500 host 150.254.166.147 tcpdump: verbose output suppressed, use -v or -vv for full protocol decode listening on eth0, link-type EN10MB (Ethernet), capture size 1500 bytes 08:40:07.623382 IP 150.254.115.58 > 150.254.166.147: IP6 2001:808:100:27::2 > 2001:808:100:27::1: ICMP6, echo request, seq 1, length 64 08:40:07.624008 IP 150.254.166.147 > 150.254.115.58: ICMP 150.254.166.147 protocol 41 unreachable, length 132 08:40:08.630480 IP 150.254.115.58 > 150.254.166.147: IP6 2001:808:100:27::2 > 2001:808:100:27::1: ICMP6, echo request, seq 2, length 64 08:40:08.631146 IP 150.254.166.147 > 150.254.115.58: ICMP 150.254.166.147 protocol 41 unreachable, length 132 IPv4 connectivity works fine. root:~# traceroute -n 150.254.166.147 traceroute to 150.254.166.147 (150.254.166.147), 30 hops max, 60 byte packets 1 150.254.115.57 0.370 ms 0.272 ms 0.322 ms 2 150.254.116.6 0.240 ms 0.228 ms 0.353 ms 3 150.254.115.5 1.416 ms 1.191 ms 0.902 ms 4 150.254.166.147 0.702 ms 1.364 ms 1.272 ms PoP is unreachable over IPv6 from outside: root@outside:~# traceroute6 -n 2001:808:100:27::1 traceroute to 2001:808:100:27::1 (2001:808:100:27::1), 30 hops max, 40 byte packets 1 2001:470:1f0a:dfd::1 35.973 ms 35.932 ms 50.739 ms 2 2001:470:0:69::1 54.875 ms 54.910 ms 54.896 ms 3 2001:470:0:168::2 52.978 ms 52.964 ms 35.817 ms 4 2001:2000:3018:1a::1 36.608 ms 36.589 ms 36.566 ms 5 2001:2000:3081:15::2 52.725 ms 52.698 ms 53.068 ms 6 2001:798:cc:1201:1e01::1 52.816 ms 39.583 ms 39.567 ms 7 2001:798:cc:1401:2201::9 39.546 ms 39.927 ms 39.893 ms 8 2001:798:cc:1401:2301::2 54.925 ms 52.122 ms 51.870 ms 9 2001:798:23:10aa::6 52.095 ms 51.971 ms 51.958 ms 10 2001:b10:c000:20e::2 51.935 ms 51.740 ms 52.459 ms 11 * * *