Problem website with code error 520

I have a Wordpress site that has 520 errors every now and then. There for example, by emptying the wordpress cache, I get this page. I contacted my networks admin to see if there is anything he can do. But I find myself stuck. I followed the Cloudflare procedure but nothing helps.

Identifiant de rayon : 6854cd5ccc21edf7


Best Regards


Error 520: web server returns an unknown error

Error 520 occurs when the origin server returns an empty, unknown, or unexpected response to Cloudflare.


A quick workaround while further investigating 520 errors is to either grey cloud the DNS record in the Cloudflare DNS app or temporarily pause Cloudflare.

Contact your hosting provider or site administrator and request a review of your origin web server error logs for crashes and to check for these common causes:

  • Origin web server application crashes
  • Cloudflare IPs not allowed at your origin
  • Headers exceeding 16 KB (typically due to too many cookies)
  • An empty response from the origin web server that lacks an HTTP status code or response body
  • Missing response headers or origin web server not returning proper HTTP error responses

520 errors are prevalent with certain PHP applications that crash the origin web server.

If 520 errors continue after contacting your hosting provider or site administrator, provide the following information to Cloudflare Support:

@nico59821 , according to Cloudflare, you must be hallucinating. The issue with intermittent 520 errors was thoroughly investigated and “fixed” by Cloudflare. The thread discussing it was closed even though most posters (including yours humbly) continued to get those errors after the “fix”: Sometimes a CF 520 error Opening a ticket doesn’t help much: after you provide details, they don’t answer for a week and then switch back to their canned response of " Error 520 is essentially a catch-all response when something unexpected happens or when the origin server incorrectly interprets or does not tolerate a request bla bla bla". AFAIK, most sufferers simply stopped using Cloudflare - the only working solution available.

This topic was automatically closed 3 days after the last reply. New replies are no longer allowed.

Hi @nico59821,

Due to the number of 520s being reported in similar circumstances, we are escalating the issue to Cloudflare Support. The original incident should have been resolved and your issue may well be unrelated.

We recommend checking these troubleshooting tips, if you haven’t already.

If you have been through these thoroughly and are not seeing corresponding issues on your network/server and you have a ticket number with Cloudflare, please reply and post that #.

To enable efficient troubleshooting by support, please ensure you include the following on the ticket:

  • example URL(s) where you are seeing the error
  • Ray IDs from the 520 pages
  • output from a traceroute from any impacted user
  • output of - replace with the affected domain.
  • Also include two HAR file(s) : one detailing your request with Cloudflare enabled on your website and the other with Cloudflare temporarily disabled - see How do I temporarily deactivate Cloudflare ?
1 Like

So as part of we fixed an issue with origins silently ending a keepalive connection that was causing very rare 520 errors.

Thus we recommend testing again - if you still see 520s - make sure you follow the guidance in our community tip here:

I dont think its resolved as we continue to get the same erorr

Ray ID: 697bb8201823c460 • 2021-10-02 06:01:59 UTC

people here on this post are desperately waiting for an answer from cloudflare

please HELP !!

Hi @simon, I commented in the original thread on Sep and the issue was solved in that moment, but now seems that the issues back. When I turned off keepalive the issues gone away. When I turn keep-alive on, the 520s errors back.

Could you please check this?

My server is in AWS (Region: us-east-1), HAProxy + NodeJS