521 error on www.kolouch.net

What is the name of the domain?

www.kolouch.net

What is the error number?

521

What is the issue you’re encountering

host not reachable when cloudflare proxy on

What steps have you taken to resolve the issue?

521 error

  • My origin server is reachable (port 443 confirmed open)
  • Apache returns HTTP 200 OK via direct IP access
  • DNS is correct
  • Proxy is enabled
  • Verified Cloudflare edge IPs are not blocked or rate-limited on my side
  • curl --resolve shows success
  • curl through Cloudflare = 521

Can you confirm whether Cloudflare is misrouting or rate-limiting 188.122.201.4?

Screenshot and curl output below.

What feature, service or problem is this related to?

I don’t know

started to work, can be closed…

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