For reproducing just try to use Kopete IM client and try to connect to some jabber server. Kopete must use IPv6 recursive DNS server for translating jabber SRV or A records. DNS server address is read from standard file /etc/resolv.conf.
So if you do not have IPv6 connectivity, you can you start some recursive (or forward) DNS server on IPv6 localhost and set nameserver ::1 in /etc/resolv.conf. This is quick hack, but should work. I see that NetworkManager on Ubuntu is already using dnsmasq (as forwarder), but does not have enabled IPv6 support on localhost. It automatically add "nameserver 127.0.0.1" line into /etc/resolv.conf. To tell dnsmasq to listen also on IPv6 localhost add configuration like: $ echo listen-address=::1 > /etc/NetworkManager/dnsmasq.d/ipv6 (and reboot) And set "nameserver ::1" in /etc/resolv.conf (note that NetworkManager is changing that file when reconnecting...) -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1527902 Title: 3.13.0-71: IPv6 UDP DNS packets are not received Status in linux package in Ubuntu: In Progress Status in linux-lts-trusty package in Ubuntu: In Progress Bug description: After upgrading linux kernel from version 3.13.0-68 to 3.13.0-71 then Kopete (IM messenger) stopped working, cannot connect to any jabber server. I started debugging this problem and found out that, problem resolve when I boot back 3.13.0-68 kernel version (without touching any system files or packages). When I boot 3.13.0-71 Kopete always does not connect. Next I debugged that problem on 3.13.0-71 is just when /etc/resolv.conf contains only IPv6 addresses of DNS servers. Problem is comes down to dns resolver (jabber in Kopete has its own for SRV records) and syscall recvfrom() (on IPv6 socket) always return error -EAGAIN without any data returned. But wireshark see that DNS response was recevied. So it looks like that after 3.13.0-68 kernel was included some change which broke receiving UDP packets via IPv6 socket. IPv4 is OK. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1527902/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp