如何让 helm hooks 只重试一次？

Question

我发现如果升级后的 helm hook 失败，它会重试 5 次然后放弃。如何确保钩子只尝试一次成功并在失败时放弃？或者我可以让 helm hook 仅在失败时在特定条件下重试，而不是总是重试？我在这里找不到此用例的任何文档/参数。

Answer 1

您可以设置 Pod 退避失败策略。

据 k8s 文档：Pod 退避失败策略：在某些情况下，由于配置等中的逻辑错误，您希望在一定次数的重试后使作业失败。为此，请在.spec.backoffLimit考虑作业之前设置为指定重试次数失败了。退避限制默认设置为 6。

添加backoffLimit: 1pod 规范，例如：

spec:
  backoffLimit: 1
  template:
    spec:
      containers:
        - name:
          image:
      
      restartPolicy: Never

完整示例：

apiVersion: batch/v1
kind: Job
metadata:
  name: {{ .Release.Name | quote }}
  labels:
    app.kubernetes.io/managed-by: {{ .Release.Service | quote }}
    app.kubernetes.io/instance: {{ .Release.Name | quote }}
  annotations:
    # This is what defines this resource as a hook. Without this line, the
    # job is considered part of the release.
    "helm.sh/hook": post-upgrade
    "helm.sh/hook-weight": "-5"
    "helm.sh/hook-delete-policy": hook-succeeded  
spec:
  backoffLimit: 1 # here
  template:
    metadata:
      name: {{ .Release.Name | quote }}
      labels:
        app.kubernetes.io/managed-by: {{ .Release.Service | quote }}
        app.kubernetes.io/instance: {{ .Release.Name | quote }}
    spec:
      restartPolicy: Never
      containers:
      - name: post-install-job
        image: "alpine:3.3"
        command: ["/bin/sleep","{{ default "10" .Values.hook.job.sleepyTime }}"]