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Kubernetes Myth #05: ClusterIP is Only for Internal Communication

🛑 The Myth:
“A ClusterIP service in Kubernetes is only for internal communication.”

✅ The Reality:
Yes, a pure ClusterIP service is internal. But… even NodePort and LoadBalancer services rely on ClusterIP!

💡 How It Actually Works:
1️⃣ Every Kubernetes service (NodePort, LoadBalancer) has a ClusterIP behind the scenes.
2️⃣ External traffic first hits the NodePort (on a node) or a LoadBalancer (via a cloud provider).
3️⃣ Kubernetes routes that traffic through ClusterIP to distribute requests across pods.

🔍 Breakdown of How Services Work:
🔹 ClusterIP: Internal communication only.
🔹 NodePort: Exposes a node’s port externally, but still forwards traffic through ClusterIP.
🔹 LoadBalancer: Cloud-managed external access, but traffic ultimately flows via ClusterIP.

📌 Bottom Line: ClusterIP isn’t just for internal traffic—it’s the core of Kubernetes networking, even for external services.

💬 Have you encountered this myth before? Let’s discuss in the comments! 👇

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