Good news! June 8th is World IPv6 Day!
Starting in late 2010 major web sites began dipping their toes into the unknown waters of IPv6 dual-stacking. What this means is that they began to advertise their servers as having both IPv4 and IPv6 addresses.
The concern with doing this is that there are several devices and applications that handle IPv6 poorly. It seems bizarre, but giving users more than one address for reaching the site can create problems, including not getting the site to load.
Until the Opera 10.5 release there was an issue with that browser where it would ‘lock on’ to an IPv6 address and refuse to fall back to IPv4 on failure. We are now playing with version 11.11 of Opera but it is a browser that runs on almost any device and not everyone keeps current. Users with a bad version of the browser would have no idea the site was fine and perfectly accessible via IPv4 making the problem rather concrete.
Apple has seemingly the most difficulty with IPv6. From OS X and iOS issues to AirPort firmware, Apple has a full basket of IPv6 concerns they have been resolving.
Overall the maturity of patches and updates means that anyone currently having IPv6 problems should be in a tiny minority and will have some self-help methods to re-connect with IPv6 sites.
The Internet Society is encouraging site owners to join in the IPv6 day by advertising an accessible IPv6 AAAA record for your site. Leaving IPv4 accessible is expected and this is not an ‘IPv6 ONLY’ day at all. The event lasts a total of 24 hours from June the 8th 00:00 to 23:59 (UTC) and participating sites will be added to a dashboard over on the ISOC website for the day.
In fact, on a very SEO note, the ISOC website is a PR8 and they are listing, in order of sign-up, all the sites that are participating in the event and they are only at 229 so far.
Here’s a direct link to the sign-up form if you wish to try IPv6 on June 8th.