WordPress gets blamed for a lot of server-layer failures. This guide helps you tell “server” from “WordPress” so you fix the right layer first.
Usually not WordPress
- Apache won’t start or reload
- PHP-FPM is down or pointing to the wrong socket
- Disk is full
Usually is WordPress
- Plugin or theme fatal errors
- Bad update logic or broken plugin after upgrade
Debug order
- Apache — configtest, status, error log
- PHP-FPM — status, correct pool/socket
- WordPress code — plugins, theme, debug log
Use WordPress 500 triage as a step-by-step flow.
FAQ
How do I know if it’s PHP-FPM?
Check Apache’s error log for proxy/fcgi or “connection refused” to a socket. Confirm PHP-FPM is running and the vhost points at the right pool. See socket mismatch.
Related
- WordPress 500 errors: fast triage — fast triage flow
- Apache log analysis for WordPress — reading Apache logs
- Fix a full root disk on Ubuntu WordPress servers — disk-full symptoms