A technical post-mortem outlines how automated traffic drove CPU usage on a Drupal 11 production platform to 94%, exposing gaps in rate limiting, Varnish cache-key handling, and application-level protection. The scenario traces the incident from the first New Relic alert through access-log analysis, Cloudflare mitigation, Varnish query-string normalization, and recovery, offering a practical view of how infrastructure weaknesses can compound under abnormal traffic.
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