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google-kubernetes-engineprometheuscadvisor

Changing promethus `job` label from `kubelet` to `kubernetes-cadvisor`


I'm working with a Google Kubernetes Engine cluster, and I want my VerticalPodAutoscalers to use Prometheus as a history provider. The instructions say:

Configure your Prometheus to get metrics from cadvisor. Make sure that the metrics from the cadvisor have the label job=kubernetes-cadvisor.

I am installing Prometheus on my cluster via Helm, using the kube-prometheus-stack chart. It appears that the default job label for cadvisor metrics in this chart is job='kubelet; I'm looking at the source code for the chart, but I don't understand how to manipulate the chart values to change the job label to kubernetes-cadvisor. What is the correct way to do this?

Under my Prometheus configuration, the only mention of cadvisor I can find is:

- job_name: monitoring/prometheus-operator-kubelet/1
  honor_labels: true
  honor_timestamps: true
  scrape_interval: 30s
  scrape_timeout: 10s
  metrics_path: /metrics/cadvisor
  scheme: https
  kubernetes_sd_configs:
  - role: endpoints
    namespaces:
      names:
      - kube-system
  bearer_token_file: /var/run/secrets/kubernetes.io/serviceaccount/token
  tls_config:
    ca_file: /var/run/secrets/kubernetes.io/serviceaccount/ca.crt
    insecure_skip_verify: true
  relabel_configs:
  - source_labels: [__meta_kubernetes_service_label_k8s_app]
    separator: ;
    regex: kubelet
    replacement: $1
    action: keep
  - source_labels: [__meta_kubernetes_endpoint_port_name]
    separator: ;
    regex: https-metrics
    replacement: $1
    action: keep
  - source_labels: [__meta_kubernetes_endpoint_address_target_kind, __meta_kubernetes_endpoint_address_target_name]
    separator: ;
    regex: Node;(.*)
    target_label: node
    replacement: ${1}
    action: replace
  - source_labels: [__meta_kubernetes_endpoint_address_target_kind, __meta_kubernetes_endpoint_address_target_name]
    separator: ;
    regex: Pod;(.*)
    target_label: pod
    replacement: ${1}
    action: replace
  - source_labels: [__meta_kubernetes_namespace]
    separator: ;
    regex: (.*)
    target_label: namespace
    replacement: $1
    action: replace
  - source_labels: [__meta_kubernetes_service_name]
    separator: ;
    regex: (.*)
    target_label: service
    replacement: $1
    action: replace
  - source_labels: [__meta_kubernetes_pod_name]
    separator: ;
    regex: (.*)
    target_label: pod
    replacement: $1
    action: replace
  - source_labels: [__meta_kubernetes_service_name]
    separator: ;
    regex: (.*)
    target_label: job
    replacement: ${1}
    action: replace
  - source_labels: [__meta_kubernetes_service_label_k8s_app]
    separator: ;
    regex: (.+)
    target_label: job
    replacement: ${1}
    action: replace
  - separator: ;
    regex: (.*)
    target_label: endpoint
    replacement: https-metrics
    action: replace
  - source_labels: [__metrics_path__]
    separator: ;
    regex: (.*)
    target_label: metrics_path
    replacement: $1
    action: replace

Solution

  • Pass the following values to Helm:

    kubelet:
      serviceMonitor:
        cAdvisor: false
    
    # Add a scrape job for cAdvisor in accordance with the Prometheus docs
    prometheus:
      prometheusSpec:
        additionalScrapeConfigs:
          - job_name: 'kubernetes-cadvisor'
            scheme: https
            metrics_path: /metrics/cadvisor
            tls_config:
              ca_file: /var/run/secrets/kubernetes.io/serviceaccount/ca.crt
            bearer_token_file: /var/run/secrets/kubernetes.io/serviceaccount/token
            kubernetes_sd_configs:
            - role: node
            relabel_configs:
            - action: labelmap
              regex: __meta_kubernetes_node_label_(.+)