SCHEDULE SUSPEND ACTIVE LAST SCHEDULE AGE
hello * * * * * False 2 2m42s 5m6s
hello * * * * * False 3 6s 5m30s
hello * * * * * False 4 6s 6m30s
hello * * * * * False 3 46s 7m10s
hello * * * * * False 1 56s 7m20s
hello * * * * * False 2 6s 7m30s
hello * * * * * False 0 26s 7m50s
hello * * * * * False 1 7s 8m31s
hello * * * * * False 0 16s 8m40s
hello * * * * * False 1 7s 9m31s
hello * * * * * False 0 17s 9m41s
hello * * * * * False 1 7s 10mIm runnig K8S cronjob and Im using the following command to watch it
kubectl get cronjobs --watch -n ns1
when watching the output Im notice that for each min there is two job
e.g. see 2m1s and 2m11s and so on …
why ? I want to run it exactly one time in every minute , how can I do that ?
hello * * * * * False 0 <none> 4s
hello * * * * * False 1 7s 61s
hello * * * * * False 0 17s 71s
hello * * * * * False 1 7s 2m1s
hello * * * * * False 0 17s 2m11s
hello * * * * * False 1 7s 3m1s
hello * * * * * False 0 17s 3m11sThis is the docker file
apiVersion: batch/v1beta1
kind: CronJob
metadata:
name: hello
namespace: monitoring
spec:
schedule: "* * * * *" # run every minute
startingDeadlineSeconds: 10 # if a job hasn't starting in this many seconds, skip
concurrencyPolicy: Forbid # either allow|forbid|replace
successfulJobsHistoryLimit: 3 # how many completed jobs should be
jobTemplate:
spec:
template:
spec:
containers:
- name: hello
image: busybox
args:
- /bin/sh
- -c
- date; echo Hello from the Kubernetes cluster
restartPolicy: OnFailureI tried also to change the schedule like "*/1 * * * *” which doesnt helps.
update
It seems that for each cronjob there is an entry like this
NAME SCHEDULE SUSPEND ACTIVE LAST SCHEDULE AGE
hello */1 * * * * False 1 0s 7sand after 10 second I see
hello */1 * * * * False 0 1 0s 17sso on... one active and the second not
I think you are looking at the wrong thing.
CronJob is spawning a Job, so you should be looking at job logs:
$ kubectl get jobs
NAME DESIRED SUCCESSFUL AGE
hello-1558019160 1 1 2m
hello-1558019220 1 1 1m
hello-1558019280 1 1 14sAs you can see there is only one spawned per minute. It's possible that the job will take longer then a minute to complete this is when concurrencyPolicy comes to play:
The
.spec.concurrencyPolicyfield is also optional. It specifies how to treat concurrent executions of a job that is created by this cron job. The spec may specify only one of the following concurrency policies:
Allow(default): The cron job allows concurrently running jobsForbid: The cron job does not allow concurrent runs; if it is time for a new job run and the previous job run hasn’t finished yet, the cron job skips the new job runReplace: If it is time for a new job run and the previous job run hasn’t finished yet, the cron job replaces the currently running job run with a new job runNote that concurrency policy only applies to the jobs created by the same cron job. If there are multiple cron jobs, their respective jobs are always allowed to run concurrently.
You can also do kubectl describe jobs hello-1558019160 in which you will see events:
Events:
Type Reason Age From Message
---- ------ ---- ---- -------
Normal SuccessfulCreate 2m job-controller Created pod: hello-1558019160-fld74
I was running your .yaml and did not saw Active jobs being higher then 1.
Hope this helps.