Apache HTTP Server

Apache 404 Surge Indicating Deployment or Configuration Issues

warning
configurationUpdated Sep 11, 2023

A sudden increase in 404 Not Found errors in Apache logs often signals missing files after deployment, incorrect DocumentRoot configuration, or broken rewrite rules rather than legitimate missing resources.

How to detect:

Monitor apache_scoreboard or access logs for increasing 404 status codes, especially when concentrated on specific URIs. Compare 404 rate before and after deployments. Check if 404s correlate with apache_uptime resets (service restarts).

Recommended action:

Parse access logs to identify most frequently requested missing resources. Verify DocumentRoot and Alias directives in apache2ctl -S output match expected paths. Check file permissions (755 for directories, 644 for files). Review .htaccess rewrite rules and VirtualHost configuration for path mismatches.