I have read and followed the "Reporting Problems" section on the Contact page and am providing the following details for this report based on the list of items stated there: my subnet is 2001:6f8:347::/48 I'm trying to reach my friend machine at tuluk.riquer.fr lion:~# tracepath6 tuluk.riquer.fr 1?: [LOCALHOST] pmtu 1280 1: 2001:6f8:347::1 0.810ms 2: gw-152.bru-01.be.sixxs.net 40.358ms 3: cl-334.bru-01.be.sixxs.net 109.569ms 4: tuluk.riquer.fr 108.350ms reached Resume: pmtu 1280 hops 4 back 4 however, I am seeing approximately 80% packet loss from my gateway: /tmp # ping6 -c 1000 tuluk.riquer.fr PING tuluk.riquer.fr (2001:6f8:39b:1:214:bfff:fe65:a5e9): 56 data bytes 64 bytes from 2001:6f8:39b:1:214:bfff:fe65:a5e9: icmp6_seq=19 ttl=62 time=2270.6 ms (...) --- tuluk.riquer.fr ping statistics --- 1000 packets transmitted, 233 packets received, 76% packet loss round-trip min/avg/max = 2195.5/2276.0/2544.9 ms when tracepath6 above fails, it can't seem to find cl-334.bru-01.be.sixxs.net lion:~# tracepath6 tuluk.riquer.fr 1?: [LOCALHOST] pmtu 1500 1: 2001:6f8:347::1 3.972ms 2: 2001:6f8:347::1 asymm 1 0.750ms pmtu 1280 2: gw-152.bru-01.be.sixxs.net 39.686ms 3: no reply (...) I can ping noc.sixxs.net without problems : /tmp # ping6 -c 10 noc.sixxs.net PING noc.sixxs.net (2001:838:1:1:210:dcff:fe20:7c7c): 56 data bytes 64 bytes from 2001:838:1:1:210:dcff:fe20:7c7c: icmp6_seq=0 ttl=51 time=1358.8 ms (...) --- noc.sixxs.net ping statistics --- 10 packets transmitted, 10 packets received, 0% packet loss round-trip min/avg/max = 1322.5/1375.8/1422.2 ms