check dns server for ipv6

netstat -an | grep ':53'

ref: http://www.linuxforums.org/forum/networking/30561-ipv6-bind-dns-server-problem.html

uneble to query whois on centos

[root@local ~]# whois apis17.info

[Querying whois.afilias.info]

[Unable to connect to remote host]

it is firewall blocking your query.

open outgoing port 43 and all done.. :)

update: whois query for IPV6 failed . then you should use debian or disable firewall temporarily (for centos)

Configserver Firewall

Click to enlarge

So far so good.

debug ipv6 connection

tcpdump -n -i eth0 proto 41

source: https://www.centos.org/modules/newbb/viewtopic.php?viewmode=thread&order=ASC&topic_id=22211&forum=40

ipv6 day

http://www.webstershome.co.uk/content/world-ipv6-day

What is World IPv6 day? - It is a trial period where a number of major web sites will provide their content on both IPv4 and IPv6. This is being sponsored by the Internet Society (ISOC) more information is posted on their World IPv6 Day page