My website has become widely inaccessible and I don't know why.
Up until recently I have been serving my website through cloudflare, so was using their nameservers. Recently I started using Route 53, so I changed to Amazon's name servers using my registrar's control panel, and found that my site quickly became unavailable (I am in the UK).
I used https://www.whatsmydns.net and found that some DNS servers around the world were not returning any namservers for my website. It was the same locations every time I tried, including London, Sao Paolo, Germany, New Zealand and parts of the US. Most locations (around 3/4) were fine though.
I was using hover.com as my registrar at the time, and I thought that the problem might have been to do with them, so I switched registrars to Amazon. Once transferred to Amazon, I changed the nameservers back to Cloudflare's nameservers, waited for it to propagate, and checked again on whatsmydns.net. It was showing up green for all locations. Then I changed back to Amazon's nameservers. The problem was exactly the same as before, the nameservers were not returned by DNS queries in the same locations.
I have changed the DNS servers on my Mac laptop, and can access my website when using the following DNS servers:
- Sky (my broadband provider) - 18.104.22.168 and 22.214.171.124
- OpenDNS Home - 126.96.36.199 188.8.131.52
But my website is inaccessible when using the following DNS servers
- Google - 184.108.40.206 and 220.127.116.11
- Cloudflare - 18.104.22.168 and 22.214.171.124
- Quad9 - 126.96.36.199 and 188.8.131.52
- CleanBrowsing - 184.108.40.206 and 220.127.116.11
- Adguard - 18.104.22.168 and 22.214.171.124
- Verisign - 126.96.36.199 and 188.8.131.52
The nameservers I am trying to use are:
I have read that some large ISPs have configured their DNS servers to violate rules, such as by indicating that a domain name does not exist just because one of its name servers does not respond. To try and diagnose if this was occurring, and there was a problem with one of the 4 nameservers, I changed yesterday to use just the first 2 nameservers in the list above, intending to then use just the second two if there was still a problem. However, even though this change has had ample time to propagate (EDIT: perhaps not, given the TTL, but it definitely seems slower than when I changed the nameservers between Amazon's and Cloudflare's and vice versa), whatsmydns.net is showing that the vast majority of DNS servers are still returning all 4 nameservers. I am not sure why that is happening.
What is going on! My website is https://www.markfisher.photo.