为什么我的 Prometheus Operator ServiceMonitor 需要 `release` 标签才能正常运行？答案

【问题标题】：Why is it that my Prometheus Operator ServiceMonitor needs a `release` label to run properly?为什么我的 Prometheus Operator ServiceMonitor 需要 `release` 标签才能正常运行？
【发布时间】：2021-11-26 16:25:00
【问题描述】：

当我部署这个时：

kind: ServiceMonitor
apiVersion: monitoring.coreos.com/v1
metadata:
  labels:
    app: complaints-monitor
    release: prometheus # <---------
  name: complaints-monitor-svc-monitor
  namespace: default
spec:
  endpoints:
    - path: /metrics
      port: web
  namespaceSelector:
    matchNames:
      - default
  selector:
    matchLabels:
      app: complaints-monitor

我的服务显示在 prometheus 目标下并正常运行。

如果我改为应用以下内容，目标就会消失：

kind: ServiceMonitor
apiVersion: monitoring.coreos.com/v1
metadata:
  labels:
    app: complaints-monitor
  name: complaints-monitor-svc-monitor
  namespace: default
spec:
  endpoints:
    - path: /metrics
      port: web
  namespaceSelector:
    matchNames:
      - default
  selector:
    matchLabels:
      app: complaints-monitor

【问题讨论】：

标签： prometheus grafana prometheus-operator

【解决方案1】：

查了kube-prometheus-stack的values.yaml后才发现这个问题

vaules.yaml

    ## If true, a nil or {} value for prometheus.prometheusSpec.serviceMonitorSelector will cause the
    ## prometheus resource to be created with selectors based on values in the helm deployment,
    ## which will also match the servicemonitors created
    ##
    serviceMonitorSelectorNilUsesHelmValues: true


    ## ServiceMonitors to be selected for target discovery.
    ## If {}, select all ServiceMonitors
    ##
    serviceMonitorSelector: {}
    ## Example which selects ServiceMonitors with label "prometheus" set to "somelabel"
    # serviceMonitorSelector:
    #   matchLabels:
    #     prometheus: somelabel

当你使用 helm 安装 kube-prometheus-stack 时，它会将标签 release: <prometheus-installed-namespace> 添加到 Kubernetes 资源中。

如果设置serviceMonitorSelectorNilUsesHelmValues 为true，则选择器将添加到prometheus.prometheusSpec.serviceMonitorSelector，在您的情况下为release: prometheus。

你应该可以看到prometheus的选择器用命令选择serviceMonitor

kubectl -n <prometheus-installed-namespace> get prometheus -o yaml

然后搜索serviceMonitorSelector。

您有两个选项可以在不添加 release 标签的情况下使其正常工作

设置serviceMonitorSelectorNilUsesHelmValues为false，那么prometheus会选择所有的serviceMonitor
或者，将serviceMonitorSelector 设置为您喜欢的任何标签。

【讨论】：