February 22, 2026
The Container Network Interface (CNI) plugin is one of the most consequential infrastructure decisions in a Kubernetes cluster. It determines how pods get IP addresses, how traffic flows between them, whether network policies are enforced, and what observability you get into network behavior. Changing CNI after deployment is painful – it typically requires draining and rebuilding nodes, or rebuilding the cluster entirely. Choose carefully up front.
February 21, 2026
Cilium replaces the traditional Kubernetes networking stack with eBPF programs that run directly in the Linux kernel. Instead of kube-proxy translating Service definitions into iptables rules and a traditional CNI plugin managing pod networking through bridge interfaces and routing tables, Cilium attaches eBPF programs to kernel hooks that process packets at wire speed. The result is a networking layer that is faster at scale, capable of Layer 7 policy enforcement, and provides built-in observability without application instrumentation.