Myth 2: Kubernetes Clusters Can't Function Without Kube-Proxy

You deploy a Kubernetes cluster and start checking the usual system components. API server? Running. Controller manager? Running. Kube-Proxy? Wait… it's missing! You double-check the namespace, logs, and even the deployment—nothing. But surprisingly, your pods and services are still communicating just fine. How is this possible? Isn't Kube-Proxy essential for cluster networking?

Why This Myth Exists?

1. Kube-Proxy is enabled by default in most Kubernetes distributions, making it appear mandatory.
2. Traditional Kubernetes networking relies on iptables or IPVS, which are managed by Kube-Proxy, reinforcing its perceived necessity.
3. Many engineers are unaware of eBPF-based networking solutions, such as Cilium, which can entirely replace Kube-Proxy while improving performance and scalability.

Reality

• Kube-Proxy is a default networking component in Kubernetes, but it is not mandatory for cluster functionality. Kubernetes networking is designed to support multiple implementations, and modern solutions can replace Kube-Proxy entirely.
• Newer networking models, such as eBPF-based CNIs (e.g., Cilium, Calico eBPF, and Katran), bypass the need for Kube-Proxy by directly handling packet processing within the kernel. These solutions not only eliminate the dependency on iptables/IPVS but also improve performance, scalability, and security by reducing latency and enabling fine-grained traffic control.
• Many high-performance Kubernetes clusters—especially those optimized for large-scale workloads—choose to disable Kube-Proxy in favor of these more efficient networking alternatives.

Experiment & Validate

Step 1: Disable Kube-Proxy Scale down Kube-Proxy to remove it from the cluster:

kubectl -n kube-system scale deployment kube-proxy --replicas=0

Step 2: Install Cilium Without Kube-Proxy Use Cilium as a replacement, enabling eBPF-based networking:

helm install cilium cilium/cilium --set kubeProxyReplacement=strict

Step 3: Deploy a Service and Test Connectivity Create an Nginx pod and expose it as a service:

kubectl run nginx --image=nginx --port=80 --expose

Now, check if the service works without Kube-Proxy:

kubectl run test-pod --image=busybox --restart=Never --rm -it -- wget -qO- nginx

If successful, you’ll see the Nginx welcome page, proving that Kubernetes networking works without Kube-Proxy.

Key Takeaways

• Kube-Proxy is NOT mandatory—Kubernetes networking can function without it.
• eBPF-based CNIs (Cilium, Calico eBPF, etc.) can fully replace Kube-Proxy, offering better performance and scalability.
• Choosing the right networking approach is crucial—understanding Kubernetes networking beyond Kube-Proxy helps optimize cluster efficiency, security, and observability.