Kubernetes - CronJob

CronJob

정의

job 컨트롤러로 실행할 Application Pod를 주기적으로 반복해서 실행
Linux의 cronjob의 스케줄링 기능을 Job Controller에 추가한 API
다음과 같은 반복해서 실행하는 Job을 운영해야 할 때 사용

• Data Backup
• Send email
• Cleaning tasks

Cronjob Schedule: "0 3 1 * *"

• Minutes (from 0 to 59)
• Hours (from 0 to 23)
• Day of the month (from 1 to 31)
• Month (from 1 to 12)
• Day of the week (from 0 to 6)

생성

옵션	설명
concurrencyPolicy	Allow:  중복실행 가능, Forbid: 중복실행 불가

root@master:~# cat > cronjob-exam.yaml
apiVersion: batch/v1
kind: CronJob
metadata:
  name: cronjob-exam
spec:
  schedule: "* * * * *"
  startingDeadlineSeconds: 300
  concurrencyPolicy: Forbid
  jobTemplate:
    spec:
      template:
        spec:
          containers:
          - name: hello
            image: busybox
            args:
            - /bin/sh			
            - "-c"
            - echo Hello; sleep 80; echo Bye
          restartPolicy: Never
root@master:~# kubectl create -f cronjob-exam.yaml 
cronjob.batch/cronjob-exam created

조회

root@master:~# kubectl get cronjobs -o wide
NAME           SCHEDULE    SUSPEND   ACTIVE   LAST SCHEDULE   AGE   CONTAINERS   IMAGES    SELECTOR
cronjob-exam   * * * * *   False     0        <none>          42s   hello        busybox   <none>
root@master:~# kubectl get pods -o wide
NAME                             READY   STATUS    RESTARTS   AGE   IP          NODE                NOMINATED NODE   READINESS GATES
cronjob-exam-27295769--1-m66lg   1/1     Running   0          17s   10.36.0.1   node1.example.com   <none>           <none>

삭제

root@master:~# kubectl delete cronjobs.batch cronjob-exam 
cronjob.batch "cronjob-exam" deleted