The problem is that your mirror is not reachable from the primary IPv6 
checking node (in France). It does not respond to ping6 when pinged from 
that node, but it does work from some other networks in Finland and U.S.

Here's a traceroute6 from the primary IPv6 mirror checking node:
$ traceroute6 -q1 -A mirrors.opencas.cn
traceroute to mirrors.opencas.cn (2001:cc0:2004:1:225:90ff:fe00:fe8b), 
30 hops max, 80 byte packets
  1  2001:4b98:dc0:41::248 (2001:4b98:dc0:41::248) [AS29169]  1.125 ms
  2  p250-core1-d-ip6.paris.gandi.net (2001:4b98:1f::c1d1:237) [AS29169] 
  3.346 ms
  3  2001:4b98:1f::c1c3:3 (2001:4b98:1f::c1c3:3) [AS29169]  3.430 ms
  4  xe0-0-1-0-core1-lux-ip6.lux.gandi.net (2001:4b98:1f::c3b2:2) 
[AS29169]  10.767 ms
  5  xe0-0-2-0-core1-lux-ip6.lux.gandi.net (2001:4b98:dc2:1f::c12:1) 
[AS29169]  10.593 ms
  6  te0-0-2-3-core2-dc1-ip6.balt.gandi.net (2001:4b98:1f::cdba:2) 
[AS29169]  99.716 ms
  7  2604:3400:dc1:12::57 (2604:3400:dc1:12::57) [AS29169]  99.774 ms
  8  te-7-1.car2.Baltimore1.Level3.net (2001:1900:2100::2ae1) [AS3356] 
99.287 ms
  9  2001:1900:4:1::26d (2001:1900:4:1::26d) [AS3356]  99.675 ms
10  vl-4062.car2.Newark1.Level3.net (2001:1900:4:1::269) [AS3356] 
103.014 ms
11  vl-4081.car1.Newark1.Level3.net (2001:1900:4:1::c5) [AS3356]  376.192 ms
12  2001:1900:4:1::ce (2001:1900:4:1::ce) [AS3356]  103.719 ms
13  2001:1900:19:5::6 (2001:1900:19:5::6) [AS3356]  103.754 ms
14  10gigabitethernet6.switch3.nyc4.he.net (2001:470:0:202::1) [AS6939] 
  86.829 ms
15  10ge10-3.core1.lax1.he.net (2001:470:0:10e::1) [AS6939]  147.922 ms
16  100ge9-1.core1.lax2.he.net (2001:470:0:72::2) [AS6939]  148.623 ms
17  *
18  2001:252:0:302::1 (2001:252:0:302::1) [*]  293.053 ms
19  2001:252:0:100::1 (2001:252:0:100::1) [*]  298.219 ms
20  2001:252:0:1::4 (2001:252:0:1::4) [*]  293.945 ms
21  2001:e18:10cc:101:102::1 (2001:e18:10cc:101:102::1) [*]  294.965 ms
22  *
23  *
24  *

You can try a traceroute6 to the other direction, the hostname is 
villisika.miuku.net. If you need to contact someone regarding this 
problem on "my end", please discuss the issue directly with the network 
admins at Gandi.

9.3.2015, 15:54, opencas kirjoitti:
> Our server support ipv6.
>
> So please let ipv6 users see our server via http://mirrorlist.centos.org/
>
> Now I see only ipv4 users in China can see our server.
>
>
> Server ipv6 address is 2001:cc0:2004:1:225:90ff:fe00:fe8b
>
> Thanks very much
>
>
>>-----BEGIN PGP SIGNED MESSAGE-----
>>Hash: SHA1
>
>>On 05/03/15 09:42, opencas wrote:
>>> HTTP:http://mirrors.opencas.cn/centos/  Sync schedule: Every 8 hrs
>>>  Bandwidth: 100Mbps Location: China Sponsor: Open Source Software
>>> Association of Chinese Academy of Sciences Sponsor URL:
>>>http://www.opencas.org/  IP to authorize: 159.226.11.160 Email
>>> contact:admin@opencas.cn  <mailto:admin@opencas.cn>
>>>
>
>>Thanks :  it has been added to the mirrors DB and will normally be
>>listed as a public mirror (and onhttp://mirror-status.centos.org  <http://mirror-status.centos.org/>  /
>
>>http://centos.org/download/mirrors/  ) in the following minutes/hours.
>>Your IP has been whitelisted (check that it's working in the following
>>hour)
>
>>Kind Regards,
>
>>- --
>
>>Fabian Arrotin
>>The CentOS Project |http://www.centos.org  <http://www.centos.org/>
>>gpg key: 56BEC54E | twitter: @arrfab
>>-----BEGIN PGP SIGNATURE-----
>>Version: GnuPG v2.0.22 (GNU/Linux)
>
>>iEYEARECAAYFAlT9PGwACgkQnVkHo1a+xU4D4gCeNH54Y9hu/yhjtVv9FETzvn4+
>>BRUAn1aGNx1ZZ1X5oOx/WqfEpJhYBkNI
>>=ZzVE
>>-----END PGP SIGNATURE-----
>
>
>
> _______________________________________________
> CentOS-mirror mailing list
> CentOS-mirror@centos.org
> http://lists.centos.org/mailman/listinfo/centos-mirror
>

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