I Built a Kubernetes Operator That Programs My Cisco Router

I wrote a Kubernetes operator in Go that talks to a Cisco 4331 router via RESTCONF. It creates VLANs, DHCP pools, and ACLs on the router, all triggered by kubectl apply . Pods get their IPs directly from the router's DHCP server, and inter-VLAN traffic is controlled by real ACLs running on real hardware. This is the full walkthrough. 1. Why? Kubernetes networking is, by default, flat. Every pod can reach every other pod. That's fine for many workloads, but in plenty of scenarios you actually want segmentation. You want the database on a different network than the web servers. You want firewall rules between them. There are better tools for this I want to be honest from the start: if you need network segmentation in Kubernetes today, use Cilium or Calico . They provide NetworkPolicy enforcement, eBPF based segmentation, encryption, observability. They work in software, they scale, and thousands of companies run them in production. That's the right answer for most people. If you're deep