520 error on website being accessed by a long URL

We’re using the free service and we have a REST service we’re accessing through an nginx server using a querystring string that is really long, ~6800 characters. The request does not appear to make it through to our service, it returns a 520 error from Cloudflare.

This could be an nginx issue however I’m not seeing any errors in those logs. Am I correct in thinking that the URL limit for Cloudflare, including query string, is 16k?

Easy way to check, what happens if you bypass Cloudflare by grey-clouding the DNS entry or using the “pause Cloudflare” option?

(wait at least 5 minutes before testing)

Hmm, the website uses SSL using the certs from CF so I created another server section for port 80 and verified I could hit that directly using curl. I repeated the request again, this time using http rather than https and got the same error.

This topic was automatically closed 15 days after the last reply. New replies are no longer allowed.