Many believe that Kube-Proxy is responsible for assigning IP addresses to Pods. But is that really the case?
❌ Myth: Kube-Proxy assigns IP addresses to Pods.
✅ Reality: The CNI (Container Network Interface) plugin handles Pod IP address allocation!
🔍 Breaking it Down
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When a Pod is created, it needs a unique IP address to communicate within the cluster. However:
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Kube-Proxy is responsible for service-level networking and load balancing across Pods.
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CNI Plugins (like Flannel, Calico, Cilium) handle Pod networking, including assigning IPs to Pods and setting up routes.
⚙️ How Pod Networking Actually Works
1️⃣ When a Pod is scheduled, Kubelet requests an IP for it.
2️⃣ The installed CNI plugin assigns an IP and configures network routes.
3️⃣ The Pod uses this IP to communicate within the cluster.
4️⃣ Kube-Proxy does not interfere with this process—it only manages routing for Kubernetes Services (e.g., ClusterIP, NodePort, LoadBalancer).
📌 Why Does This Matter?
If a Pod isn’t getting an IP, the issue is likely with the CNI plugin, not Kube-Proxy.
Misconfiguring the CNI plugin can lead to network failures in your cluster.
Understanding the difference helps in debugging Kubernetes networking issues more efficiently.
