This CKAD practice question tests your understanding of application observability and maintenance. This is a configuration task: choose the command set that satisfies every stated requirement. Small differences — like 'secret' vs 'password' or 'transport input ssh' vs 'all' — change whether the answer is correct. After answering, compare your reasoning against the explanation and wrong-answer breakdown below. Once you have made your selection, read the full explanation to reinforce the concept and understand why each distractor is designed to mislead on exam day.
You need to configure a liveness probe that checks if the container port 8080 is open. Which probe type should you use?
tcpSocket
tcpSocket probe succeeds if the TCP handshake completes.
grpc
Why wrong: grpc probe uses gRPC health checking protocol.
exec
Why wrong: Exec runs a command inside the container.
httpGet
Why wrong: This checks HTTP response, not just port open.
Answer choices
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
tcpSocket
A tcpSocket probe is the correct choice when you need to verify that a container is listening on a specific TCP port, such as port 8080. It works by attempting to open a TCP connection to the specified port; if the connection succeeds, the probe is considered successful. This is ideal for checking basic network-level readiness or liveness without requiring an HTTP endpoint or a custom command.
Key principle: Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Answer analysis
For each option: why learners choose it and why it is or isn't the right answer here.
tcpSocket
Why this is correct
tcpSocket probe succeeds if the TCP handshake completes.
Related concept
Read the scenario before looking for a memorised answer.
grpc
Why it's wrong here
grpc probe uses gRPC health checking protocol.
exec
Why it's wrong here
Exec runs a command inside the container.
httpGet
Why it's wrong here
This checks HTTP response, not just port open.
Common exam traps
The trap here is that candidates often choose httpGet because they assume a web server on port 8080, but the question explicitly asks only to check if the port is open, not to validate an HTTP response, making tcpSocket the precise and minimal probe type.
Trap categories for this question
Command / output trap
Exec runs a command inside the container.
Detailed technical explanation
Under the hood, a tcpSocket probe uses the kubelet's network stack to initiate a three-way TCP handshake with the container's IP and port. If the handshake completes (SYN, SYN-ACK, ACK), the probe succeeds; if it fails (e.g., connection refused or timeout), the probe fails. A subtle behavior is that tcpSocket probes do not validate the data exchanged after the handshake, so they only confirm the port is open, not that the application is fully functional. In real-world scenarios, this is useful for services like databases or message queues that listen on TCP but may not expose an HTTP endpoint.
Key takeaway
Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Real-world example
A practitioner preparing for the CKAD exam encounters this exact type of scenario on the job. The correct answer here is not the most general option — it is the best answer for the specific constraint described. Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option. Real exam questions reward reading the full scenario before eliminating options, because the constraint defines which answer fits.
What to study next
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
Application Observability and Maintenance — study guide chapter
Learn the concepts, then practise the questions
Application Observability and Maintenance practice questions
Targeted practice on this topic area only
All CKAD questions
991 questions across all exam domains
Certified Kubernetes Application Developer CKAD study guide
Full concept coverage aligned to exam objectives
CKAD practice test guide
How to use practice tests most effectively before exam day
Related practice questions
Use these pages to review the topic behind this question. This is how one missed question becomes focused revision.
Practise CKAD questions linked to Application Design and Build.
Practise CKAD questions linked to Application Deployment.
Practise CKAD questions linked to Application Environment, Configuration and Security.
Practise CKAD questions linked to Application Observability and Maintenance.
Practise CKAD questions linked to Services and Networking.
Practise CKAD questions linked to CKAD fundamentals.
Practise CKAD questions linked to CKAD scenario.
Practise CKAD questions linked to CKAD troubleshooting.
Practice this exam
Short sessions build daily habit. Longer sessions build exam-day stamina. Try a timed session to simulate real conditions.
FAQ
Application Observability and Maintenance — This question tests Application Observability and Maintenance — Read the scenario before looking for a memorised answer..
The correct answer is: tcpSocket — A tcpSocket probe is the correct choice when you need to verify that a container is listening on a specific TCP port, such as port 8080. It works by attempting to open a TCP connection to the specified port; if the connection succeeds, the probe is considered successful. This is ideal for checking basic network-level readiness or liveness without requiring an HTTP endpoint or a custom command.
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
Read the scenario before looking for a memorised answer.
About these practice questions
Courseiva creates original exam-style practice questions with explanations and wrong-answer analysis. It does not publish real exam questions, exam dumps, or protected exam content. Learn why practice questions differ from exam dumps →
Last reviewed: Jun 25, 2026
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.
Question Discussion
Share a tip, memory trick, or ask about the reasoning behind this question. Do not post real exam questions, leaked content, braindumps, or copyrighted exam material. Comments are moderated and may be removed without notice.
Sign in to join the discussion.