Ubuntu
linux package

  1. Bug #1584042
  2. Comment #9

Comment 9 for bug 1584042

Revision history for this message
Frédéric Druilhet (frederic-druilhet) wrote : Re: IPV6 resolving fails via udp (not tcp) from other server

========== TcpDump =========

---- from the client ----
root@14Ext-NS:~# tcpdump host 14Ext-Code.dr14.cnrs.fr -v
tcpdump: listening on eth0, link-type EN10MB (Ethernet), capture size 262144 bytes
18:27:46.837544 IP6 (flowlabel 0x9a4b5, hlim 64, next-header UDP (17) payload length: 50) 14Ext-Code.dr14.cnrs.fr.46138 > 14Ext-NS.dr14.cnrs.fr.domain: [bad udp cksum 0xe623 -> 0x2df7!] 50905+ [1au] A? www.google.fr. (42)
18:27:49.195988 IP6 (flowlabel 0x4b7e2, hlim 64, next-header UDP (17) payload length: 212) 14Ext-NS.dr14.cnrs.fr.domain > 14Ext-Code.dr14.cnrs.fr.46138: [bad udp cksum 0x203e -> 0xa01b!] 50905 1/4/5 www.google.fr. A 216.58.210.227 (204)
18:27:49.196277 IP6 (flowlabel 0x4b7e2, hlim 64, next-header UDP (17) payload length: 212) 14Ext-NS.dr14.cnrs.fr.domain > 14Ext-Code.dr14.cnrs.fr.46138: [bad udp cksum 0x203e -> 0x301c!] 50905 1/4/5 www.google.fr. A 216.58.210.227 (204)
18:27:51.837791 IP6 (flowlabel 0x9a4b5, hlim 64, next-header UDP (17) payload length: 50) 14Ext-Code.dr14.cnrs.fr.46138 > 14Ext-NS.dr14.cnrs.fr.domain: [bad udp cksum 0xe623 -> 0x2df7!] 50905+ [1au] A? www.google.fr. (42)
18:27:51.838131 IP6 (flowlabel 0x4b7e2, hlim 64, next-header UDP (17) payload length: 212) 14Ext-NS.dr14.cnrs.fr.domain > 14Ext-Code.dr14.cnrs.fr.46138: [bad udp cksum 0x203e -> 0x421c!] 50905 1/4/5 www.google.fr. A 216.58.210.227 (204)
18:27:54.208962 IP6 (hlim 255, next-header ICMPv6 (58) payload length: 32) fe80::215:fdff:fefd:fd10 > 14Ext-Code.dr14.cnrs.fr: [icmp6 sum ok] ICMP6, neighbor solicitation, length 32, who has 14Ext-Code.dr14.cnrs.fr
   source link-address option (1), length 8 (1): 00:15:fd:fd:fd:10
18:27:54.209228 IP6 (hlim 255, next-header ICMPv6 (58) payload length: 24) 14Ext-Code.dr14.cnrs.fr > fe80::215:fdff:fefd:fd10: [icmp6 sum ok] ICMP6, neighbor advertisement, length 24, tgt is 14Ext-Code.dr14.cnrs.fr, Flags [solicited]
^C
7 packets captured

------ from the nameserver --------
root@14Ext-Code:~# tcpdump host 14Ext-NS.dr14.cnrs.fr -v
tcpdump: listening on eth0, link-type EN10MB (Ethernet), capture size 262144 bytes
18:27:41.607983 IP6 (flowlabel 0x9a4b5, hlim 64, next-header UDP (17) payload length: 50) 14Ext-Code.dr14.cnrs.fr.46138 > 14Ext-NS.dr14.cnrs.fr.domain: [bad udp cksum 0x1f9c -> 0x2df7!] 50905+ [1au] A? www.google.fr. (42)
18:27:46.607895 IP6 (flowlabel 0x9a4b5, hlim 64, next-header UDP (17) payload length: 50) 14Ext-Code.dr14.cnrs.fr.46138 > 14Ext-NS.dr14.cnrs.fr.domain: [bad udp cksum 0x1f9c -> 0x2df7!] 50905+ [1au] A? www.google.fr. (42)
18:27:46.620713 IP6 (hlim 255, next-header ICMPv6 (58) payload length: 32) fe80::215:5dff:fe01:140e > 14Ext-NS.dr14.cnrs.fr: [icmp6 sum ok] ICMP6, neighbor solicitation, length 32, who has 14Ext-NS.dr14.cnrs.fr
   source link-address option (1), length 8 (1): 00:15:5d:01:14:0e
18:27:46.621042 IP6 (hlim 255, next-header ICMPv6 (58) payload length: 24) 14Ext-NS.dr14.cnrs.fr > fe80::215:5dff:fe01:140e: [icmp6 sum ok] ICMP6, neighbor advertisement, length 24, tgt is 14Ext-NS.dr14.cnrs.fr, Flags [solicited]
18:27:48.966683 IP6 (flowlabel 0x4b7e2, hlim 64, next-header UDP (17) payload length: 212) 14Ext-NS.dr14.cnrs.fr.domain > 14Ext-Code.dr14.cnrs.fr.46138: [bad udp cksum 0x5848 -> 0xa01b!] 50905 1/4/5 www.google.fr. A 216.58.210.227 (204)
18:27:48.966974 IP6 (flowlabel 0x4b7e2, hlim 64, next-header UDP (17) payload length: 212) 14Ext-NS.dr14.cnrs.fr.domain > 14Ext-Code.dr14.cnrs.fr.46138: [bad udp cksum 0xe848 -> 0x301c!] 50905 1/4/5 www.google.fr. A 216.58.210.227 (204)
18:27:51.608023 IP6 (flowlabel 0x9a4b5, hlim 64, next-header UDP (17) payload length: 50) 14Ext-Code.dr14.cnrs.fr.46138 > 14Ext-NS.dr14.cnrs.fr.domain: [bad udp cksum 0x1f9c -> 0x2df7!] 50905+ [1au] A? www.google.fr. (42)
18:27:51.608773 IP6 (flowlabel 0x4b7e2, hlim 64, next-header UDP (17) payload length: 212) 14Ext-NS.dr14.cnrs.fr.domain > 14Ext-Code.dr14.cnrs.fr.46138: [bad udp cksum 0xfa48 -> 0x421c!] 50905 1/4/5 www.google.fr. A 216.58.210.227 (204)
^C
8 packets captured

I'm noticing this bad udp cksum. I'll make some searches