CKAD — Managing Jobs & CronJobs

Managing Jobs and CronJobs

This page covers the essential kubectl commands for working with Jobs and CronJobs — listing, inspecting, deleting, and troubleshooting.

List and Inspect

# List all Jobs
kubectl get jobs

# List all CronJobs
kubectl get cronjobs

# Describe a Job (includes events and Pod status)
kubectl describe job backup-job

# Describe a CronJob
kubectl describe cronjob db-backup

# Check logs from a Job's Pod
kubectl logs job/backup-job

# Get Job YAML
kubectl get job backup-job -o yaml

Viewing Job Pods

# List Pods created by a specific Job
kubectl get pods -l job-name=backup-job

# List Pods created by all Jobs
kubectl get pods --selector=batch.kubernetes.io/job-name

# Watch Pods in real time
kubectl get pods -l job-name=backup-job -w

Delete Jobs and CronJobs

# Delete a Job (and its Pods)
kubectl delete job backup-job

# Delete a CronJob (and all its Jobs)
kubectl delete cronjob db-backup

# Delete all completed Jobs
kubectl delete jobs --field-selector status.successful=1

Important: Deleting a CronJob also deletes all Jobs it has created. Deleting a Job also deletes its Pods.

Suspend and Resume a CronJob

# Pause a CronJob (stops creating new Jobs)
kubectl patch cronjob db-backup -p '{"spec":{"suspend":true}}'

# Resume it
kubectl patch cronjob db-backup -p '{"spec":{"suspend":false}}'

# Verify
kubectl get cronjob db-backup
# SUSPEND column should show True or False

Manually Trigger a CronJob

# Create a one-time Job from a CronJob's template
kubectl create job db-backup-manual --from=cronjob/db-backup

# Check it ran
kubectl get jobs
kubectl logs job/db-backup-manual

This is useful for testing a CronJob without waiting for the next scheduled run.

Troubleshooting Jobs

Common Job Statuses

Status	Meaning
Complete	All completions succeeded
Failed	backoffLimit reached or activeDeadlineSeconds exceeded
Active	Pods are still running
Suspended	Job is paused

Debugging Workflow

# 1. Check Job status
kubectl get job <name>

# 2. Get detailed events
kubectl describe job <name>

# 3. List the Job's Pods
kubectl get pods -l job-name=<name>

# 4. Check Pod logs
kubectl logs <pod-name>

# 5. Check Pod events (for scheduling or image pull issues)
kubectl describe pod <pod-name>

Common CronJob Issues

Problem	Cause	Fix
Jobs not being created	CronJob is suspended	Check suspend field
Missed schedules	startingDeadlineSeconds too low	Increase the deadline
Too many Jobs piling up	History limits too high	Set successfulJobsHistoryLimit
Overlapping Jobs causing issues	concurrencyPolicy: Allow	Switch to Forbid or Replace

Quick Reference

Task	Command
List Jobs	kubectl get jobs
List CronJobs	kubectl get cronjobs
Describe Job	kubectl describe job <name>
Job logs	kubectl logs job/<name>
Job Pods	kubectl get pods -l job-name=<name>
Delete Job	kubectl delete job <name>
Delete CronJob	kubectl delete cronjob <name>
Suspend CronJob	kubectl patch cronjob <name> -p '{"spec":{"suspend":true}}'
Manual trigger	kubectl create job <name> --from=cronjob/<cron-name>

Exam tip: The command kubectl create job <name> --from=cronjob/<cron-name> is extremely useful during the exam for testing CronJobs without waiting for the schedule.

---

Next: Put it all together with Jobs & CronJobs Lab →