Create a scheduled task (CronJob)¶

This page introduces how to create a cron job (CronJob) through mirror images and YAML files.

Scheduled tasks (CronJob) are suitable for performing periodic operations, such as backup and report generation. These tasks can be configured to repeat periodically (for example: daily/weekly/monthly), and the time interval at which the task starts to run can be defined.

Prerequisites¶

Before creating a scheduled task (CronJob), the following prerequisites need to be met:

• In the Container Management module Access Kubernetes Cluster or Create Kubernetes Cluster, and can access the cluster UI interface.

• Create a namespace and a user.

• The current operating user should have NS Edit or higher permissions, for details, please refer to Namespace Authorization.

• When there are multiple containers in a single instance, please make sure that the ports used by the containers do not conflict, otherwise the deployment will fail.

Mirror creation¶

Refer to the following steps to create a scheduled task using the image.

1. Click Cluster List on the left navigation bar, and then click the name of the target cluster to enter the Cluster Details page.

2. On the cluster details page, click Workload -> Scheduled Task in the left navigation bar, and then click the Image creation button in the upper right corner of the page.

3. Fill in Basic Information, Container Configuration, Timed Task Configuration, [Advanced Configuration] in turn ](create-cronjob.md#_6), click OK in the lower right corner of the page to complete the creation.

   The system will automatically return to the timed task list. Click ︙ on the right side of the list to perform operations such as updating, deleting, and restarting the scheduled task.

Basic Information¶

On the Create Scheduled Task page, enter the information according to the table below, and click Next.

• Payload Name: Can contain up to 63 characters, can only contain lowercase letters, numbers, and a separator ("-"), and must start and end with a lowercase letter or number. The name of the same type of workload in the same namespace cannot be repeated, and the name of the workload cannot be changed after the workload is created.
• Namespace: Select which namespace to deploy the newly created scheduled task in, and the default namespace is used by default. If you can't find the desired namespace, you can go to Create a new namespace according to the prompt on the page.
• Description: Enter the description information of the workload and customize the content. The number of characters should not exceed 512.

Container configuration¶

Container configuration is divided into six parts: basic information, life cycle, health check, environment variables, data storage, and security settings. Click the corresponding tab below to view the configuration requirements of each part.

Container configuration is only configured for a single container. To add multiple containers to a pod, click + on the right to add multiple containers.

Timing task configuration¶

• Concurrency strategy: Whether to allow multiple Job tasks to run in parallel.

  • Allow: A new scheduled task can be created before the previous task is completed, and multiple tasks can be parallelized. Too many tasks may occupy cluster resources.
  • Forbid: Before the previous task is completed, a new task cannot be created. If the execution time of the new task is up and the previous task has not been completed, CronJob will ignore the execution of the new task.
  • Replace: If the execution time of the new task is up, but the previous task has not been completed, the new task will replace the previous task.

  The above rules only apply to multiple jobs created by the same CronJob. Multiple tasks created by multiple CronJobs are always allowed to run concurrently.

• Timing rules: Set the time period for task execution based on minutes, hours, days, weeks, and months. Support custom Cron expressions with numbers and *, after inputting the expression, the meaning of the current expression will be prompted. For detailed expression syntax rules, please refer to Cron Schedule Syntax.

• Task records: Set how many records of successful or failed tasks to keep. 0 means do not keep.
• Timeout: When this time is exceeded, the task will be marked as failed to execute, and all Pods under the task will be deleted. When it is empty, it means that no timeout is set. The default is 360 s.
• Number of retries: the number of times the task can be retried, the default value is 6.
• Restart Policy: Set whether to restart the Pod when the task fails.

Advanced configuration¶

The advanced configuration of scheduled tasks mainly involves labels and annotations.

You can click the Add button to add labels and annotations to the workload instance Pod.

YAML creation¶

In addition to mirroring, you can also create timed tasks more quickly through YAML files.

1. Click Cluster List on the left navigation bar, and then click the name of the target cluster to enter the Cluster Details page.

2. On the cluster details page, click Workload -> Scheduled Task in the left navigation bar, and then click the YAML Create button in the upper right corner of the page.

3. Enter or paste the YAML file prepared in advance, click OK to complete the creation.

apiVersion: batch/v1
kind: CronJob
metadata:
  creationTimestamp: '2022-12-26T09:45:47Z'
  generation: 1
  name: demo
  namespace: default
  resourceVersion: '92726617'
  uid: d030d8d7-a405-4dcd-b09a-176942ef36c9
spec:
  concurrencyPolicy: Allow
  failedJobsHistoryLimit: 1
  jobTemplate:
    metadata:
      creationTimestamp: null
    spec:
      activeDeadlineSeconds: 360
      backoffLimit: 6
      template:
        metadata:
          creationTimestamp: null
        spec:
          containers:
            - image: nginx
              imagePullPolicy: IfNotPresent
              lifecycle: {}
              name: container-3
              resources:
                limits:
                  cpu: 250m
                  memory: 512Mi
                requests:
                  cpu: 250m
                  memory: 512Mi
              securityContext:
                privileged: false
              terminationMessagePath: /dev/termination-log
              terminationMessagePolicy: File
          dnsPolicy: ClusterFirst
          restartPolicy: Never
          schedulerName: default-scheduler
          securityContext: {}
          terminationGracePeriodSeconds: 30
  schedule: 0 0 13 * 5
  successfulJobsHistoryLimit: 3
  suspend: false
status: {}

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