Dockers dunkle Seite - IPv6

Augenscheinlich macht Docker IPv6 (Host) => NAT => IPv4 (im Container)
curl ipv6.dckg.net -vL
* Rebuilt URL to: ipv6.dckg.net/
* Hostname was NOT found in DNS cache
* Trying 2a03:b0c0:3:d0::2209:5001...
* Connected to ipv6.dckg.net (2a03:b0c0:3:d0::2209:5001) port 80 (#0)
> GET / HTTP/1.1
> User-Agent: curl/7.38.0
> Host: ipv6.dckg.net
> Accept: */*
>
< HTTP/1.1 301 Moved Permanently
< Location: https://ipv6.dckg.net/
< Content-Length: 0
< Date: Thu, 24 Nov 2016 18:43:14 GMT
<
* Connection #0 to host ipv6.dckg.net left intact
* Issue another request to this URL: 'https://ipv6.dckg.net/'
* Found bundle for host ipv6.dckg.net: 0x7f30028bbb00
* Hostname was NOT found in DNS cache
* Trying 2a03:b0c0:3:d0::2209:5001...
* Connected to ipv6.dckg.net (2a03:b0c0:3:d0::2209:5001) port 443 (#1)
* successfully set certificate verify locations:
* CAfile: none
CApath: /etc/ssl/certs
* SSLv3, TLS handshake, Client hello (1):
* SSLv3, TLS handshake, Server hello (2):
* SSLv3, TLS handshake, CERT (11):
* SSLv3, TLS handshake, Server key exchange (12):
* SSLv3, TLS handshake, Server finished (14):
* SSLv3, TLS handshake, Client key exchange (16):
* SSLv3, TLS change cipher, Client hello (1):
* SSLv3, TLS handshake, Finished (20):
* SSLv3, TLS change cipher, Client hello (1):
* SSLv3, TLS handshake, Finished (20):
* SSL connection using TLSv1.2 / ECDHE-RSA-AES256-GCM-SHA384
* Server certificate:
* subject: CN=dckg.net
* start date: 2016-10-31 22:01:00 GMT
* expire date: 2017-01-29 22:01:00 GMT
* subjectAltName: ipv6.dckg.net matched
* issuer: C=US; O=Let's Encrypt; CN=Let's Encrypt Authority X3
* SSL certificate verify ok.
> GET / HTTP/1.1
> User-Agent: curl/7.38.0
> Host: ipv6.dckg.net
> Accept: */*
>
< HTTP/1.1 200 OK
< Strict-Transport-Security: max-age=63072000;
< Content-type: text/plain;charset=UTF-8
< Transfer-Encoding: chunked
< Date: Thu, 24 Nov 2016 18:43:15 GMT
<

172.17.0.1


* Connection #1 to host ipv6.dckg.net left intact


Unter
ipv4.dckg.net
ipv6.dckg.net

verbirgt sich dieses PHP-Script:
<?php
    $ipv = strpos($_SERVER['REMOTE_ADDR'], ':') ? 6 : 4;
    header("Content-Type: text/css");
    echo "/*<!-- ಠ_ಠ -->*/\n";
    echo "table.ipcheck #ipcheck-ipv$ipv:before {content: \"" . $_SERVER['REMOTE_ADDR'] . "\";}";
    echo "\n";
    echo "table.ipcheck #ipcheck-ipv$ipv {background-color: lightgreen;}";
?>

, was die IP auf der IP-Check Seite im Blog angibt.

Nur gibt er halt eben eine lokale IPv4 zurück, obwohl von Außen (Host) per IPv6 verbunden wird.
NAT ist dreckig!

Es gibt bei Docker AFAIK keine simple Option, einem Container direkt eine IPv6 zuzuweisen.
IPv6 with Docker - Docker
Klar, dem Docker Interface weist man optimalerweise ein /64-er Prefix zu, allerdings wählt er die Container-IPs nach Zufallsprinzip aus. AFAIK.
Eine --ipv6= Option für docker run wäre ideal.