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Thoughts on engineering, design, and building great products.
Wiring Up Pod Networking by Hand: CNI bridge and VPC Routes
The previous theory article laid the groundwork; this one does the assembly. We write the CNI bridge + host-local config for each worker, add routes in the VPC route table so pod-to-pod across nodes works, then watch the two nodes finally flip to Ready. At the end we create two real pods on two different nodes and ping between them — each pod gets an IP from its node's range, and packets cross nodes without NAT.
The Kubernetes Network Model
Before wiring up pod networking in the next article, you need to understand what kind of network model Kubernetes demands: one IP per pod, every pod talking directly with no NAT. This article walks through the model's four foundational requirements, the four kinds of in-cluster communication, why pod-to-pod across nodes is the hard part, the two families of solutions (overlay and native routing), and where CNI fits — laying the groundwork for the hands-on wiring next.