CKAD Services and Networking Practice Question

Answer analysis

Option-by-option breakdown

For each option: why learners choose it and why it is or isn't the right answer here.

• ✓

  NodePort

  Why this is correct

  NodePort exposes a service by allocating a static port (in the default 30000-32767 range) on every node in the cluster. Clients reach the service by connecting to any node's IP address at that port, and kube-proxy forwards the traffic to the service's ClusterIP, which then load-balances to endpoint pods. Since the port is open on all nodes, this type directly satisfies the requirement for node-level external exposure.

• ✗

  ClusterIP

  Why it's wrong here

  ClusterIP creates a virtual IP address that is only accessible from inside the cluster, so external traffic cannot reach it directly. Its sole purpose is to provide a stable internal service endpoint and load balancing across pods, but it does not open any port on the node's network interfaces. Therefore, it cannot expose a service externally via each node.

• ✗

  LoadBalancer

  Why it's wrong here

  LoadBalancer relies on an external cloud controller to provision a managed load balancer with a public IP, and the service's traffic is forwarded to node ports underneath. It does not itself open a port that is independently accessible on every node; instead, it implicitly creates a NodePort service and delegates all routing to the cloud provider's load balancer. Because exposure is via a single cloud-managed endpoint, it is not the correct answer for 'exposes via each node'.

• ✗

  ExternalName

  Why it's wrong here

  ExternalName is a special service that returns a CNAME record pointing to a fully qualified domain name, so it performs no port mapping and has no backing pods or endpoints. It is only used to provide an internal alias for services hosted outside the cluster, and it never opens any node port. Consequently, it cannot expose anything externally via node IPs.

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