It started with a WHM/Cpanel problem
On my WHM/Cpanel server, I had two websites. I am going to call them website A and B. There were no redirections between them. However, When I typed res.websitea.com, it redirected to website B. I rebuilt the HTTPD configuration file. I have deactivated features. I have checked all .conf files, and I could not find the root cause of the problem. One day, I decided to deactivate IPv6 and the redirection was gone in an IPv4 only environment. I have deleted my IPv6 settings and recreated my IPv6 settings. Then, I re-activated IPv6 and the redirection didn’t come back. However, I didn’t trust IPv6 anymore.
Ipv6 raises some concerns
This problem was a very serious problem because it created a redirection from one account to another. IPv6 does not bring any benefits for webmasters (speed, security, SEO). So, if it generates additional problems it is useless to activate IPv6 for your websites. After this issue with IPv6, I wondered if IPv6 could not trigger SEO problems and be responsible for a drop in traffic. At the beginning, I thought that all the big websites had an IPv6 support but I have discovered most of them don’t have IPv6 support. Then, we can start wondering if IPv6 is well accepted by Googlebot and bingbot because the number of websites with IPv6 support is very small.