Cloudflare 520 Errors with Cloudflare Disabled

[openevo]

I have been using Cloudflare for several years, and never had any problems. And a few weeks ago, random Cloudflare 520 errors started happening.

Server logs show no errors. I’ve checked everything from the system level to the domain level.

Always Online is turned off, and I’m running Full SSL on the Cloudflare side.

I disabled Cloudflare, turning off the orange cloud in the DNS and disabling Cloudflare protection from within the dashboard, and the Cloudflare 520 errors are still happening.

When I refresh the Cloudflare 520 error, the page loads fine. But the error repeats itself on random pages and random times.

I’ve looked through the Cloudflare troubleshooting guide for 520 errors, but that does not help. How can I see the exact error that Cloudflare is seeing from the web server to generate the 520 error?

Please advise.

[sdayman]

@openevo

I disabled Cloudflare, turning off the orange cloud in the DNS

After 5 minutes, this should have stopped. Who’s your web host? Would you mind sharing your domain name?

[openevo]

I did not wait five minutes. I thought it resolved quicker.

Let me try again. Thanks.

[sdayman]

@openevo

I thought it resolved quicker.

TTL (Time To Live) for Cloudflare DNS is 5 minutes.

[openevo]

You are right. After around five minutes, Cloudflare is no longer enabled on the site. The SSL Certificate shows from the server side, not the Cloudflare side.

And no errors. Not one.

How can I determine what is flagging an error to Cloudflare to produce the 520 error?

[sdayman]

Welcome to the 520 party.

https://community.cloudflare.com/search?q=520%20order%3Alatest

Maybe you’ll luck out and it will be something here:

Community Tip - Fixing Error 520: Web server is returning an unknown error

Error Try the suggestions in this Community Tip to help you fix “Error 520: Web server is returning an unknown error”. Background 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 due to a protocol violation or an empty response. A 520 error occurs when the connection started on the origin web server, but that the request was not completed. The most common reason why this would occur …

[openevo]

Yeah, I’ve read through that and it doesn’t offer much guidance. I can understand for a new setup, but I’ve been running for years and never had any problems, not to mention you cannot repeat a pattern because the errors are completely random. Frustrating, to say the least.

[openevo]

Is there any way to request Cloudflare show what errors from the web server are producing the Cloudflare 520 errors?