Uninstalling nginx does not automatically remove its configuration files or disable the service, which often leaves residual routing rules active. To resolve persistent 404 errors, you must verify that the service is completely stopped, purge leftover configuration directories, and ensure your Apache server is correctly binding to port 80.
Verify Nginx Service Status
The most common reason for a lingering 404 error is that the nginx process continues to run in the background despite being removed via apt-get remove. Package managers on Ubuntu often leave configuration files and running daemons intact to prevent accidental data loss. You need to explicitly stop the service to free up port 80.
Run the following command to check if nginx is still active:
systemctl status nginxIf the output shows active (running), the service is still handling incoming requests. Stop it immediately using:
sudo systemctl stop nginxTo prevent it from starting again on boot, disable the service:
sudo systemctl disable nginxIf the service was already stopped but the issue persists, proceed to purge the package entirely to remove all associated configuration files.
Purge Nginx Configuration Files
Simply removing the binary does not delete the sites-enabled configurations that may be redirecting traffic incorrectly. These residual files can cause nginx to serve default pages or return 404s if the proxy settings are misconfigured even after the main package is gone.
Use the purge option with apt to remove both the package and its configuration files:
sudo apt-get purge nginx nginx-common nginx-full nginx-coreAfter purging, clean up any unused dependencies:
sudo apt-get autoremoveCheck the /etc/nginx/ directory to ensure it no longer exists or contains only empty remnants. If directories remain, manually remove them:
sudo rm -rf /etc/nginxEnsure Apache Listens on Port 80
Once nginx is fully removed, your Apache HTTP Server should take over serving web content. However, Apache might fail to start if port 80 is still occupied by another process or if it is configured to listen on a different port.
Verify that Apache is running and listening on the correct port:
sudo systemctl status apache2Check the Apache configuration to ensure it binds to port 80. Open the ports configuration file:
sudo nano /etc/apache2/ports.confEnsure the line Listen 80 is present. If you see Listen 8080 or similar, change it to 80 and restart Apache:
sudo systemctl restart apache2If Apache fails to start, check the error log for details:
sudo tail -n 20 /var/log/apache2/error.logClear Browser Cache and DNS
Browsers aggressively cache HTTP responses, including 404 errors. Even after fixing the server configuration, your browser may continue to display the old cached error page. Clearing this cache is essential to see the updated content served by Apache.
In Chrome or Firefox, use the hard refresh shortcut Ctrl + F5 (or Cmd + Shift + R on macOS). For a more thorough clear, go to your browser settings and clear browsing data, ensuring "Cached images and files" is selected.
Additionally, DNS propagation delays might cause your domain to point to an old IP address or cached records. Flush your local DNS cache by restarting the networking service:
sudo systemctl restart systemd-resolvedYou can also try accessing your site using the server's IP address directly to bypass DNS issues entirely. If the site loads correctly via IP, the problem lies with your DNS registrar or local resolver.
Check Firewall Rules
Ubuntu systems often use UFW (Uncomplicated Firewall) to manage network traffic. If UFW is enabled, it might block incoming connections on port 80, resulting in timeouts that browsers sometimes interpret as 404s depending on the client behavior.
Check the firewall status:
sudo ufw statusIf it is active, allow HTTP traffic:
sudo ufw allow 'Apache Full'This rule allows both HTTP (80) and HTTPS (443) traffic through the firewall, ensuring Apache can receive requests from external users.
Related Resources
If you are setting up additional services alongside your web server, consider how they interact with port bindings. For example, when configuring backend services, refer to How to Host a Local Server for Android Applications on Ubuntu to avoid port conflicts. Additionally, understanding location directives helps in troubleshooting complex routing issues, as seen in Creating List of URLs from Nginx Location Directive.
Frequently Asked Questions
Why does my domain still show 404 after removing nginx?
The nginx service likely remains active or retains configuration files that intercept requests. You must stop the service with systemctl stop nginx and purge its config files to release control of port 80 back to Apache.
How do I confirm Apache is serving my site?
Access your server's IP address directly in your browser instead of using the domain name. If the site loads via IP but not domain, the issue is DNS-related; if it fails on both, Apache is not running or configured correctly.
What if port 80 is still busy after uninstalling nginx?
Another process may be using port 80. Use sudo lsof -i :80 to identify the conflicting process and terminate it with kill -9 [PID] before restarting Apache.
Does clearing browser cache fix all 404 errors?
No, it only fixes cached error responses. If the server is misconfigured, clearing the cache will simply reload the new incorrect response. Always verify server logs first.
Can I reinstall nginx accidentally while trying to fix this?
Yes, some dependency packages might pull nginx back in. Avoid installing packages that suggest nginx as a recommendation unless necessary, and always check dpkg -l | grep nginx to ensure it is fully purged.