Description of problem: When connecting to an IPv6-only Bittorrent tracker, Transmission reports that the "Tracker responded: No Response (0)". Looking at Wireshark sniffing logs, the truth of the matter is that Transmission requests only an A (IPv4) record from DNS and never asks for an AAAA (IPv6) record. Version-Release number of selected component (if applicable): transmission-1.72-1.fc11.i586 How reproducible: Use transmission to handle any .torrent files from http://www.sixxs.net/tools/tracker/catalog/ Actual results: Transmission issues A record lookup, receives no address and never tries an AAAA record and reports "Tracker responded: No Response (0)". Expected results: Transmission should ask for an AAAA record as well and then use the AAAA IPv6 record to connect to tracker to get peers list. Additional info: If I configure Transmission to use my IPv6-enable Squid proxy, Transmission will be able to send an IPv4 request to the proxy which will resolve the ipv6-only hostname to an AAAA record and relay the IPv6 request to the tracker and get the peers list. Once Transmission connects to the tracker via an IPv6-enabled proxy, it works just fine from this point on talking to ipv6-only peers. Transmission also works just fine with an IPv4 tracker with IPv6 peers (or a mix of IPv6 & IPv4 peers). Unknown if using an IPv6 address for the tracker URL will work. Editing the tracker to use http://[2001:838:1:1:210:dcff:fe20:7c7c]/announce produces no results, as the tracker must not be configured to answer to this to this IPv6 address instead of the hostname.
In talking with others at Freenode#ipv6, this is a known issue. The tracker lookup has been hard-coded to ipv4, as using ipv6 was causing issues and needs to be re-written to handle either situation properly.