Hi, you can do traceroutes with Port 123/UDP, so you can determine where the filtering begins:
traceroute6 -U -p 123 2001:4b98:dc0:41:216:3eff:fe69:46e3 First of all: I have no problems contacting your server, so maybe there's a filtering which was only temporarily enabled (due to ongoing DDoS attacks) or it only affects specific prefixes or uplinks. For 2001:4b98:dc0:41:216:3eff:fe69:46e3 I did a traceroute from my connection at home. I put it in a pastebin, because it's better readable there than in my e-mail: http://pastebin.com/raw.php?i=4QYp2Unz For comparison the same destination with ICMP6 Echo-Req: http://pastebin.com/raw.php?i=wtWT7d0J Either the last hop before your server is filtering those requests or the firewall on your server does. Since it is no other hop between 2001:4b98:1f::c3d3:250 and your server it's a bit difficult to find out. Or maybe your NTP service does not respond... Are there any known monitoring server IPv6 addresses? Maybe you could do a traceroute originating from Port 123 to one of those monitoring servers to be sure. Greetings Max Am 05.04.2014 14:40, schrieb Rainer May: > > > Am 05.04.2014 11:00, schrieb Anssi Johansson: > >> I can query my server successfully from other IPv6-enabled hosts, >> but not from my Linode virtual machine. The routing is fine, but >> apparently there's some filtering going on somewhere. > > apparently this filtering is somewhere near your client. Because > > parrot ~ # ip -6 a s dev eth0 > 2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qlen 1000 > inet6 2001:470:96b9:1:b4b8:dd06:a1c:223/64 scope global > > parrot ~ # ntpdate -q 2001:4b98:dc0:41:216:3eff:fe69:46e3 > server 2001:4b98:dc0:41:216:3eff:fe69:46e3, stratum 3, offset > -104.099471, delay 0.08322 > 5 Apr 13:47:45 ntpdate[25271]: step time server > 2001:4b98:dc0:41:216:3eff:fe69:46e3 offset -104.099471 sec > > Strange looking is the offset - it's rather 2 minutes off from my GPS > time source? > > > OTOH, Markkus's box does not respond to queries right now: > > parrot ~ # ntpdate -q 2001:4b98:dc0:41:216:3eff:fee9:a26 > server 2001:4b98:dc0:41:216:3eff:fee9:a26, stratum 0, offset 0.000000, > delay 0.00000 > 5 Apr 13:51:28 ntpdate[25286]: no server suitable for synchronization > found > > > However, the monitoring is anything but reliable. One of my servers > was removed from the pool recently due to being "unreachable" (by > IPv4!) - even as it still has approx. 400 clients connecting without > problems (and it receives it's own time from the German PTB next > door). *shrugs* > _______________________________________________ > pool mailing list > [email protected] > http://lists.ntp.org/listinfo/pool > _______________________________________________ pool mailing list [email protected] http://lists.ntp.org/listinfo/pool
