Tagged: CNI

23 July 2026 Linux Container Networking Networking CNI Kubernetes

Container Networking Deep Dive Part 5: What CNI Actually Is

Kubernetes doesn't use Docker's networking model. It defines a plugin interface instead, CNI, with a lifecycle of exactly two verbs. Why one-IP-per-pod forced that split, and what a CNI plugin actually does when a pod starts.
23 July 2026 Linux Container Networking Networking CNI Cilium

Container Networking Deep Dive Part 6: CNI Plugins Compared, Flannel, Calico, and Cilium

Three CNI plugins solve the same ADD-verb reachability problem three different ways: VXLAN encapsulation, BGP-distributed routes, and an eBPF datapath. The architecture and datapath differences, not a feature-checklist bake-off.
23 July 2026 Linux Container Networking Networking Cilium CNI

Container Networking Deep Dive Part 8: Network Policy Enforcement Compared, iptables vs eBPF

The same Kubernetes NetworkPolicy resource gets enforced completely differently depending on the CNI plugin underneath it. Calico's default path turns it into iptables rule chains; Cilium turns it into eBPF map lookups keyed on pod identity. Same intent, different mechanism, different failure modes.