I should have specified, I did read the FAQ about the error, but just in case:
- if the firewall had actual rules to block Cloudflare, it wouldn’t be intermittent
- server is running, works without the proxy, and as specified the requests don’t reach it when we get the errors
- no network issues that I am aware of, I have monitoring tools and the website without the proxy wouldn’t work if it was purely network related
- not sure how the SSL certificate could be linked to intermittent 521 errors but you have the URL, if you think the certificate isn’t right, let me know
- already done
I need help with the packet captured from the router to better understand why the requests sometimes don’t reach the server.