Error 520 unknow connection issue

Hello i am new here sorry so not sure where to post
we have this error recently we use ips latest update
( there is an unknow connection issue betwwen cloudflare and the origine web server.As a result: the web page can not be displayed ) this happen times to times and when we do refresh we can read the forums/sections
thanks in advance for your helps

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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:

I don’t get the error

this happened times to times
our site hoster cleared the cache
so let see…
i will forward to you
thanks for your help

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:

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