nginx: 404 Not Found

What the message looks like

2026/10/29 09:41:03 [error] 1234#1234: *7788 open() "/var/www/example.com/html/about" failed (2: No such file or directory), client: 203.0.113.5, server: example.com, request: "GET /about HTTP/2.0", host: "example.com"

Common causes

• The root or alias points to the wrong directory, or the deployment did not put the files there.
• An application with pretty URLs (front controller, single-page app) lacks try_files ... /index.php?$args or /index.html.
• The request reached the wrong server block (wrong server_name or the default_server).
• File names are case-sensitive on Linux: Logo.PNG is not logo.png.
• A location with alias has a trailing-slash mismatch, or a regex location overrides the intended one.

Check

1. The exact path nginx tried
   sudo tail -n 20 /var/log/nginx/error.logCopy
2. The effective rules of the server
   nginx -T 2>/dev/null | grep -nE 'server_name|root |alias |try_files|location 'Copy
3. Does the file exist at that path?
   ls -l /var/www/example.com/html/aboutCopy
4. Which server block answers this host? (check the response)
   curl -sI -H 'Host: example.com' http://127.0.0.1/about | head -n 5Copy

Fix

• Compare the path from the error log with the real file location and correct root or alias, or deploy the missing files.
• For front-controller apps use location / { try_files $uri $uri/ /index.php?$args; }, for single-page apps try_files $uri /index.html;.
• Check server_name so that the host matches the intended block, and set a deliberate default_server.
• Fix the case of file names or links, and with alias make the location and alias slashes match.
• Test and apply: nginx -t && systemctl reload nginx.

FAQ

How is a 404 different from 403?

404 means nginx found no matching file. 403 means it found the path but may not read it or may not list the directory, which is a permission or index problem.

Can a 404 come from the application and not from nginx?

Yes. If PHP-FPM or a proxy backend answers 404, nginx only passes it on. The error log has no open() failed line in that case, so check the application routing.