Error 522 When using cloudflare with ipv4("A") record, but server is open for all ip's


#1

Hello,
I am using cloudeFlare as a DNS service to all my websites using sub domains please look at the image below,

I have a problem that I cannot solve, I have an machine with an IPv4 (who except connections from 0.0.0.0/0 and runs on port 80) that always return 522 when accessed from cloudFlare, using the IP in the url or using curl works without issues.
I do not understand why doesn’t the “A” records works ? I am sure that the server does not block cloudflare.
can someone please help?
Many thanks


#2

Have you tried using curl with that IP from a foreign (not yours) network? i.e. 4G connection?

The reason I am asking is that if this IP happens to be on your PC at home for example, maybe the PC allows the connections in, but the network in between does not (e.g. you’re behind CGNAT which means that your outside IP in front of the world is different from the IP you get assigned from your ISP, or alternatively you’re not behind CGNAT but your home router that is the actual holder of said IP address does not have the proper DNAT/firewall rules to allow that traffic to cross the WAN->LAN border)