Since OS X 10.9 DNS is broken.

Hello!

The problem with work ipv6-only sites in versions 10.9, 10.10 and 10.11. In 10.8 all good.

If Network Services not have ipv6 address then dns not resolving ipv6-only sites in browsers.

In Terminal (ping6, traceroute6, telnet) all work.

I have problem with resolving ipv6-only hosts in browsers when use vpn with tap-adapter [ipv4 and ipv6].

Wi-Fi (ipv4)

$ ifconfig en0
en0: flags=8863<UP,BROADCAST,SMART,RUNNING,SIMPLEX,MULTICAST> mtu 1500
  ether 5c:f9:38:8c:d4:96
  inet 172.20.10.2 netmask 0xfffffff0 broadcast 172.20.10.15
  media: autoselect
  status: active

VPN (ipv4 + ipv6)

$ ifconfig tap0
tap0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> mtu 1403
  ether 32:55:92:f2:d7:0e
  inet 130.193.34.11 netmask 0xffffff00 broadcast 130.193.34.255
  inet6 fe80::3055:92ff:fef2:d70e%tap0 prefixlen 64 scopeid 0xa
  inet6 2a02:6b8:0:4::b prefixlen 64
  nd6 options=1<PERFORMNUD>
  open (pid 1178)

In Terminal ipv6-only hosts work fine:

$ host ipv6.google.com
ipv6.google.com is an alias for ipv6.l.google.com.
ipv6.l.google.com has IPv6 address 2a00:1450:4010:c03::8b
$
$ ping6 -c 1 ipv6.google.com
PING6(56=40+8+8 bytes) 2a02:6b8:0:4::b --> 2a00:1450:4010:c0b::8b
16 bytes from 2a00:1450:4010:c0b::8b, icmp_seq=0 hlim=56 time=71.288 ms


--- ipv6.l.google.com ping6 statistics --
1 packets transmitted, 1 packets received, 0.0% packet loss
round-trip min/avg/max/std-dev = 71.288/71.288/71.288/0.000 ms
95: ~ $
95: ~ $ telnet ipv6.google.com 80
Trying 2a00:1450:4010:c0b::8b...
Connected to ipv6.l.google.com.
Escape character is '^]'.
Work!
HTTP/1.0 400 Bad Request
Content-Type: text/html; charset=UTF-8
Content-Length: 1555
Date: Mon, 18 Apr 2016 14:44:33 GMT

But in Safari i see "Safari can not find the server."

Create manually Network Service when I connect to VPN not good workaround.

Maybe someone found a solution to the problem?