Blackbox Monitoring vs Internal Metrics - The Gap Between "Healthy" and "Working" (opens in new tab)

You've probably had this incident. Dashboards are all green. CPU is fine. Memory looks good. Pods aren't restarting. Databases are healthy. But customers can't log in, or payments won't process, or nothing's loading. You check Prometheus. Nothing's firing. Everything says "we're fine." Except you're not fine. A healthy system is not the same as a working system. The Blind Spot Most monitoring setups measure what's happening inside the infrastructure. CPU utilization. Memory consumption. Disk ...