IPv6 tracker "Not Working" on qBT 4.0.2

[changrui0608]

qBittorrent version and Operating System

qBT v4.0.2 (64-bit)
Windows 10 Pro x64

What is the problem

Everything works fine if tracker is IPv4, and in this case I can connect to both v4 and v6 peers.
When the tracker server is IPv6 only, the tracker status is always "not working", and cannot connect to any peer.

I have checked "Listen on IPv6 address" in options in settings, and restart a lot of times.

Extra info(if any)

I think in an old qBT 3.0.x or 3.1.x version (I think in that version there isn't "Listen on IPv6 address" option in settings), eveything works fine. In that version qBT can download from any tracker and peer.

Since there are many BT sites that is IPv6 only in China education network, this is a bit important for our Chinese students...

uTorrent works fine with the same PC, same network, just tested. I just prefer qBT than uT if possible...

Another advice ---
It will be good if change "Listen on IPv6 address" settings to options with "IPv4 only", "IPv6 only" and "Both". This will be helpful for us since many universities in China provides free IPv6 network and chargable IPv4 network.

[changrui0608]

I just tried 3.3.16 on this Windows PC and a MacBook (macOS), everything works fine.
It can download from IPv6 tracker and IPv6 peer, no matter "Listen on IPv6 address" is checked or not.

[HenryHu]

This bug also appears on OpenSUSE, using qBittorrent 4.0.3.
The error on both windows and linux are the same:

Address family not supported by protocol

On the other hand, it seems to work on FreeBSD, so there is some implementation differences.

[HenryHu]

I have discovered that my FreeBSD system was using libtorrent-rasterbar 1.1.4. After manually updating to 1.1.6, I found that it also fails to work on FreeBSD. After reversing to 1.1.4, it works again.
I think that it's related to some changes in libtorrent-rasterbar.

[HenryHu]

I created an upstream issue:
arvidn/libtorrent#2689

[Weegley]

The same in version 4.2.0 on Windows.
I have 1 win7 pc, and 3 win10 pc's. Same version of Qbittorrent 4.2.0. Same issue on all of them whe uTorrent works with ipv6 trackers on same pc's.
MacOS version 4.2.1 work partly (http://[2001.....] works, but http://ipv6... not.) Ipv6 sites work fine on all a/m pc's
Screenshot from win pc:
https://b.radikal.ru/b13/2001/36/f0d7e2d21b04.png

[gky99]

IPv6 tracker not working on 4.2.1 Windows.
Rolling back to 4.1.9.1 works fine. It might be an issue of libtorrent again.

[thalieht]

Fixed in libtorrent.

[thalieht]

IPv6 tracker not working on 4.2.1 Windows.
Rolling back to 4.1.9.1 works fine. It might be an issue of libtorrent again.

Well... the original problem was fixed. If there is a regression again make another issue.

[FranciscoPombal]

Cannot reproduce with recent qBittorrent/libtorrent versions.