CKAD Services and Networking Practice Question
Which Service type is used to expose a Service on a static port on each node's IP address, allowing external traffic to reach the Service?
⚠ Common exam trap
Some candidates mistakenly think LoadBalancer is the only external Service type, but the question specifies a static port on each node's IP, which is the definition of NodePort. LoadBalancer builds on NodePort and adds an external load balancer.
Answer choices
Why each option matters
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
NodePort
NodePort is the correct Service type because it exposes the Service on a static port (in the range 30000-32767) on each node's IP address. This allows external traffic to reach the Service by sending requests to any node's IP at that port, which then forwards traffic to the appropriate Pods via the ClusterIP and kube-proxy rules.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
ClusterIP
Why it's wrong here
ClusterIP assigns an internal virtual IP from the cluster's private service CIDR that is reachable only from within the cluster. It does not create any listener on the host nodes' network interfaces, nor does it allocate a static port on each node's IP address. To access a ClusterIP service from outside the cluster, you must use an explicit proxy, port-forward, or a separate ingress/load balancer mechanism, so it fails the requirement of exposing on a static per-node port.
- ✗
ExternalName
Why it's wrong here
ExternalName is a special service type that creates a DNS CNAME record mapping the service name to an external domain name, such as db.example.com. It never defines any endpoints, ports, or IP addresses of its own, so there is no underlying selector or pod backing it. Because it only provides DNS-level indirection, it cannot expose any port on node IPs, making it entirely incompatible with the stated requirement.
- ✓
NodePort
Why this is correct
NodePort is the only service type that opens a specific static port (in the 30000–32767 range by default) on every node in the cluster, forwarding traffic from that port to the service's ClusterIP and then to the selected pods. This directly matches the requirement: each node's IP address becomes an external entry point on that same fixed port. It is the underlying primitive that a LoadBalancer service uses when it provisions cloud infrastructure.
- ✗
LoadBalancer
Why it's wrong here
A LoadBalancer provisions an external cloud load balancer with a single, stable IP address, not a static port on each node’s IP address. The stem explicitly requires exposure on every node’s IP, which is the mechanism of a NodePort Service. It is tempting because LoadBalancer is the standard way to expose a Service to the internet in cloud environments, and it would be correct if the requirement were for a single external IP rather than per-node static ports.
Go deeper
Related to this question
About these practice questions
Courseiva writes every CKAD question from scratch — 160 in total, each with an explanation and a wrong-answer breakdown. None are copied from real exams or dumps. Learn why practice questions differ from exam dumps →
JA
Written by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
This CKAD practice question is part of Courseiva's free CNCF certification practice question bank. Courseiva provides original exam-style practice questions with explanations, topic-based practice, mock exams, readiness tracking, and study analytics to help learners prepare for the CKAD exam.