CKAD Application Design and Build Practice Question
Which YAML snippet correctly defines a CronJob that runs a task every 5 minutes?
⚠ Common exam trap
The CKAD exam often tests the distinction between `*/5 * * * *` (every 5 minutes) and `0 */5 * * *` (every 5 hours), which is a classic trap where candidates confuse the minute and hour fields in cron syntax.
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
✓
schedule: "*/5 * * * *"
The standard cron expression for 'every 5 minutes' is `*/5 * * * *`, which matches the required five fields (minute, hour, day of month, month, day of week). Kubernetes CronJob uses this exact format, where `*/5` in the minute field means 'every 5 minutes' and the four asterisks mean 'every hour, every day, every month, every weekday'.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
schedule: "*/5 * * *"
Why it's wrong here
This cron expression has only four fields (minute, hour, day of month, month) and omits the required fifth field for day of week. Standard cron syntax in Kubernetes requires exactly five fields separated by spaces, so this schedule is invalid and would be rejected when creating the CronJob. It cannot be used to run a job every 5 minutes.
- ✓
schedule: "*/5 * * * *"
Why this is correct
This is the standard five-field cron expression where the minute field uses the step operator */5, meaning it matches minutes 0, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, and 55. Since all other fields (hour, day of month, month, day of week) are wildcards, the job executes every five minutes around the clock, exactly as required.
- ✗
schedule: "0 */5 * * *"
Why it's wrong here
In this expression the minute field is pinned to 0 while the hour field contains */5, indicating a step of five hours. That means the job only triggers at minute zero of every fifth hour, such as 00:00, 05:00, and 10:00, which is once every five hours rather than every five minutes. This does not satisfy the requirement.
- ✗
schedule: "* * * * *"
Why it's wrong here
A wildcard in every field makes this schedule fire at the start of each minute, because the minute field matches all 60 possible values and the remaining fields are also unrestricted. Running the job every minute is far more frequent than every five minutes, so it would create an excessive number of Kubernetes Job objects and violate the intended cadence.
Go deeper
Related to this question
About these practice questions
One of 826 original CKAD practice questions on Courseiva, each with a full explanation and wrong-answer analysis — not exam dumps or protected exam content. 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.