Checklists for software errors, setup, and tool workflows.

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Fix Nginx Upstream Connection Refused Behind Cloudflare

If you see upstream connection refused in your Nginx error logs while using Cloudfla...

Setup Cloudflare Origin Certificate for Nginx

If you use Cloudflare as a reverse proxy, enabling HTTPS between Cloudflare and your Nginx server...

How to Stop Nginx Redirect Loop: Practical Fixes

An Nginx redirect loop (too many redirects) usually appears as a browser error after multiple 301...

Fix Cloudflare Wildcard Subdomain Not Working with WordPress

You set up a wildcard DNS record in Cloudflare (e.g., *.example.com) expecting all subdomains to ...

Fix Docker Compose Port Already Allocated on Linux

You run docker-compose up and get an error like Error starting userland proxy:...

Fixing Cloudflare 522 Errors Caused by Server Resource Exhaustion
If you're seeing a Cloudflare 522 error, it means your web server is not responding in time. ...