Kubernetes Networking: Part 1 — Why Services Exist

2026.06.17

Replace this with your real opening: the specific moment you hit the problem — pods getting new IPs on every restart, and your app breaking because it cached the old one.

The problem

Describe the mechanism, not just the symptom. What did you run to confirm it? Paste the actual output.

$ kubectl get pods -o wide
NAME          IP           NODE
my-app-7f9c   10.244.1.12  node-2

What a Service actually does

This is where you go one layer deeper than most tutorials — trace the iptables rules, or the eBPF program, or the DNS record, that a Service creates.

$ iptables -t nat -L KUBE-SERVICES -n | grep my-app

Keep going until you've explained the mechanism, not just named it.