Part 2 of the security fundamentals series. The networking concepts you need to reason about exposure: IP and MAC addresses, ports, TCP versus UDP, common services, and how to see what your own hosts are listening on.
Kubernetes announced the retirement of ingress-nginx, with best-effort maintenance ending in March 2026. This is the plan we used to inventory annotations, map them to Gateway API, run both side by side and cut over host by host without downtime.
Our analytics VPC could reach the shared services VPC, and shared services could reach the payments VPC, but analytics timed out connecting to payments. VPC peering does not route traffic through a middle VPC. How we proved it, the options, and why we moved to Transit Gateway.