Home / browser-issues / Fix Cloudflare 521 Error on Nginx: Step-by-Step Guide - How to Fix Nginx 'Upstream Connection Refused' Error-Fix 'git remote origin already exists' on GitHub

Fix Cloudflare 521 Error on Nginx: Step-by-Step Guide - How to Fix Nginx 'Upstream Connection Refused' Error-Fix 'git remote origin already exists' on GitHub

Updated 2026-07-28 14:55:19browser-issues

Fix Cloudflare 521 Error on Nginx: Step-by-Step Guide - How to Fix Nginx 'Upstream Connection Refused' Error-Fix 'git remote origin already exists' on GitHub

Prepare

Execute

Validate

Document

Operational follow-up

Record the exact option, command, or setting that changed the result.
Keep a rollback note if the workflow affects shared files or team settings.

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