kubernetes - 计划重启Kubernetes Pod而不造成停机

Question

我有6个正在运行的Pod副本，我想每5分钟重新启动\重新创建一次。

这需要进行滚动更新-以便不会立即终止所有更新，也不会造成停机。我该如何实现？

我尝试使用cron作业，但似乎无法正常工作:

apiVersion: batch/v1beta1
kind: CronJob
metadata:
  name: scheduled-pods-recreate
spec:
  schedule: "*/5 * * * *"
  concurrencyPolicy: Forbid
  jobTemplate:
    spec:
      template:
        spec:
          containers:
          - name: ja-engine
            image: app-image
            imagePullPolicy: IfNotPresent
          restartPolicy: OnFailure

尽管作业已成功创建并按照以下说明进行了调度，但它似乎从未运行过:

Name:                       scheduled-pods-recreate
Namespace:                  jk-test
Labels:                     <none>
Annotations:                <none>
Schedule:                   */5 * * * *
Concurrency Policy:         Forbid
Suspend:                    False
Starting Deadline Seconds:  <unset>
Selector:                   <unset>
Parallelism:                <unset>
Completions:                <unset>
Pod Template:
  Labels:  <none>
  Containers:
   ja-engine:
    Image:           image_url
    Port:            <none>
    Host Port:       <none>
    Environment:     <none>
    Mounts:          <none>
  Volumes:           <none>
Last Schedule Time:  Tue, 19 Feb 2019 10:10:00 +0100
Active Jobs:         scheduled-pods-recreate-1550567400
Events:
  Type    Reason            Age   From                Message
  ----    ------            ----  ----                -------
  Normal  SuccessfulCreate  23m   cronjob-controller  Created job scheduled-pods-recreate-1550567400

那么第一件事，如何确保它正在运行，以便重新创建Pod？

另外，如何确保没有停机时间？

cronjob的更新版本:

apiVersion: batch/v1beta1
kind: CronJob
metadata:
  name: hello
spec:
  schedule: "*/1 * * * *"
  jobTemplate:
    spec:
      template:
        spec:
          containers:
          - name: hello
            image: busybox
            args:
            - /bin/sh
            - -c
            - kubectl patch deployment runners -p '{"spec":{"template":{"spec":{"containers":[{"name":"jp-runner","env":[{"name":"START_TIME","value":"'$(date +%s)'"}]}]}}}}' -n jp-test
          restartPolicy: OnFailure

pods 未以消息“重启后重启失败的容器和错误”开头，如下所示:

State:          Terminated
      Reason:       Error
      Exit Code:    127

Answer 1

从Kubernetes 1.15开始，您可以使用以下命令执行滚动重启。

kubectl rollout restart deployment <deployment name>