When the Kubernetes API went silent: A three-layer networking mystery

Every support engineer has a case that stays with them. The one that comes up at team lunches. The one where, even after it's resolved, you find yourself staring at a packet capture at midnight just to make sure you really understand what happened. This is that case. It started in January 2026 with a support ticket that read deceptively simply: pods are intermittently failing to reach the Kubernetes API server. The error was a familiar-looking timeout. The customer had already ruled out their own operators. What none of us knew yet was that we were looking at three separate bugs — in three dif