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Hands-on Lab·Kubernetes and Cloud Native Security Associate

kube-proxy and Service Implementation

A Service is not a process. It is a set of packet-rewriting rules that kube-proxy programs on every node, which is why kube-proxy is one of the most privileged Pods in the cluster and why a Service has no traffic to intercept.

Cluster Component Security Guide 15 of 42 Intermediate

Written against the versions above. kube-proxy in iptables mode - `mode: ""` defaults to iptables on Linux. Cilium is installed with `kubeProxyReplacement=false`, so kube-proxy is genuinely doing this work rather than being decorative.

The cka5001 cluster: one control plane and 3 schedulable workers, on Cilium.
Server NameIP AddressOSRolesCPURAMHDD
CKA5001192.168.0.41Ubuntu 26.04 LTSControl Plane Node (tainted NoSchedule)2 Core4 GB50 GB
CKA5001-NODE01192.168.0.42Ubuntu 26.04 LTSWorker Node2 Core4 GB50 GB
CKA5001-NODE02192.168.0.43Ubuntu 26.04 LTSWorker Node2 Core4 GB50 GB
CKA5001-NODE03192.168.0.44Ubuntu 26.04 LTSWorker Node2 Core4 GB50 GB

Before you start

  1. The most privileged Pod on the node

  2. A Service, as rules

  3. The identity it runs as

Official sources