Wrong IPv6 in cache
Sometimes Firefox is having a wrong IPv6 in cache. Using the extension SixOrNot, I can see for rss.forumanalogue.fr the following IPv6 2001:41d0:fecf:8900:216:3eff:fe65:97bc, with the note "Cache". However, this IP corresponds to toot.forumanalogue.fr and the actual IPv6 for rss.forumanalogue.fr is 2001:41d0:fecf:8900:216:3eff:fef1:20a2. In order to temporary fix the issue, I perform a dig and it solves the issue for a while.
It is a rather new issue (few weeks).
What is going on?
Alle svar (4)
A check with the DSN Lookup tool (about:networking#dnslookuptool) confirms the IPs you posted although only the IPv6 differs (they have the same IPv4), so that might have caused it.
- rss.forumanalogue.fr: 18.104.22.168 2001:41d0:fecf:8900:216:3eff:fef1:20a2
- toot.forumanalogue.fr : 22.214.171.124 2001:41d0:fecf:8900:216:3eff:fe65:97bc
It is possible that the SixOrNot extension is broken or otherwise is malfunctioning and display wrong info.
Ændret af cor-el den
Sorry for the late answer, I had some health issues.
It is not linked to the extension SixOrNot. Indeed, I have the same issue with other computers on my network which don't have this extension installed. They are also using different DNS resolvers, which makes me wonder if Firefox is ignoring the system DNS resolvers. For all tested computers, other web browsers are working properly, tested with w3m and Chromium.
I checked the link Firefox can't load websites but other browsers can It appears unlikely that this issue fit in any enumerated cases. I thought that it can come from DNS Prefetching, however, there is no X-DNS-Prefetch-Control in any of the HTTP headers for any of the involved website. I guess that if it was about cache and cookies, the issue would not be random.
The fact that these websites have the same IPv4 and different IPv6 should not be a problem. As far as I know, there is no such constrain in RFCs. If Firefox cannot handle this properly, then, it is a bug.