How to Fix Cloudflare 521 Error During Setup
If you see a 521 error after setting up Cloudflare, it means your origin server refused the conne...
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Fixing Cloudflare 521 Error After Server Restart
You restart your server, wait for it to come back up, then visit your site—only to see a Cloudfla...
Fix Cloudflare Error 521 After a Server Update
If you see Cloudflare error 521 after updating your server, the origin web server is refusing the...