Jobs & CronJobs
A Job runs a task to completion; a CronJob runs Jobs on a repeating schedule.
schedule: "minute hour day-of-month month day-of-week"Not every workload runs forever. Batch tasks — a data import, a backup, a report — should run once and finish. Kubernetes has two objects for this.
Jobs
A Job runs one or more Pods until a specified number succeed, then stops. If a Pod fails, the Job retries it (up to backoffLimit times). Set completions and parallelism to run many at once.
CronJobs
A CronJob creates Jobs on a schedule using standard cron syntax. Perfect for nightly backups or hourly cleanups.
| Field | Meaning |
|---|---|
* * * * * | minute, hour, day-of-month, month, day-of-week |
0 2 * * * | every day at 02:00 |
*/15 * * * * | every 15 minutes |
Example
apiVersion: batch/v1
kind: CronJob
metadata:
name: nightly-backup
spec:
schedule: "0 2 * * *"
jobTemplate:
spec:
template:
spec:
restartPolicy: OnFailure
containers:
- name: backup
image: myorg/backup-tool:1.0
args: ["--target", "s3://my-bucket/db"]When to use it
- A data team uses a Job to run a one-off database migration script after deploying a new application version.
- A SaaS platform runs a nightly CronJob to generate and email usage reports to each tenant automatically.
- A CI pipeline creates a Job to run the full integration test suite against a staging environment after every merge to main.
More examples
One-off Job manifest
Defines a Job that runs a migration script once; on failure the pod restarts, on success the Job is marked Complete.
apiVersion: batch/v1
kind: Job
metadata:
name: db-migration
spec:
template:
spec:
containers:
- name: migrate
image: myapp-migrations:1.0
command: ["./migrate.sh"]
restartPolicy: OnFailureCronJob for nightly reports
Schedules a report-generator container to run daily at 2 AM using standard cron syntax.
apiVersion: batch/v1
kind: CronJob
metadata:
name: nightly-report
spec:
schedule: "0 2 * * *" # 2 AM every day
jobTemplate:
spec:
template:
spec:
containers:
- name: reporter
image: report-generator:1.0
restartPolicy: OnFailureMonitor Job completion
Checks job completion status, reads logs from the Job's pod, then cleans up the completed Job resource.
kubectl get jobs
# NAME COMPLETIONS DURATION AGE
# db-migration 1/1 12s 2m
kubectl logs job/db-migration
kubectl delete job db-migration
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