k8s CronJob定時任務

1. Cronjob定時任務

• CronJob用於實現定時任務，像Linux的Crontab一樣。

  • 定時任務

• 應用場景：通知，備份

• 示例代碼

  [root@k8s-master deployment]# vim cronjob.yaml
  [root@k8s-master deployment]# cat cronjob.yaml 
  apiVersion: batch/v1beta1
  kind: CronJob
  metadata:
    name: hello
  spec:
    schedule: "*/1 * * * *"
    jobTemplate:
      spec:
        template:
          spec:
            containers:
            - name: hello
              image: busybox
              args:
              - /bin/sh
              - -c
              - date; echo Hello aliang
            restartPolicy: OnFailure
  
  

2. 案例

• 編寫定時任務配置

  [root@k8s-master deployment]# vim cronjob.yaml
  [root@k8s-master deployment]# cat cronjob.yaml 
  apiVersion: batch/v1beta1
  kind: CronJob
  metadata:
    name: hello
  spec:
    schedule: "*/1 * * * *"
    jobTemplate:
      spec:
        template:
          spec:
            containers:
            - name: hello
              image: busybox
              args:
              - /bin/sh
              - -c
              - date; echo Hello aliang
            restartPolicy: OnFailure
  
  

• 執行啟動

  [root@k8s-master deployment]# kubectl apply -f cronjob.yaml 
  cronjob.batch/hello created
  

• 查詢運行狀態

  [root@k8s-master deployment]# kubectl get cronjob
  NAME    SCHEDULE      SUSPEND   ACTIVE   LAST SCHEDULE   AGE
  hello   */1 * * * *   False     0        56s             19m
  
  [root@k8s-master deployment]# kubectl get pods
  NAME                     READY   STATUS      RESTARTS   AGE
  hello-1606896780-rcrm8   0/1     Completed   0          2m21s
  hello-1606896840-tt8dw   0/1     Completed   0          81s
  hello-1606896900-tghzz   0/1     Completed   0          21s
  pi-7bbgz                 0/1     Completed   0          43m
  

• 查看日志

  [root@k8s-master deployment]# kubectl logs hello-1606896900-tghzz
  Wed Dec  2 08:15:13 UTC 2020
  Hello aliang