IPv6 support was added to TeamSpeak 3 server version 3.0.13. It's also possible to use IPv6 addresses in the query_ip_whitelist.txt, query_ip_blacklist.txt and tsdns_settings.ini. Please note, that you need to set the IPv6 inside square brackets in the tsdns_settings.ini (and only there) like this: ipv6-ts3.example.com=[2606:2800:220:1:248:1893:25c8:1946]:9987
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