Monitor only one namespace metrics - Prometheus with Kubernetes

Question

I am implementing Prometheus to monitor my Kubernetes system health, where I have multiple clusters and namespaces.

My goal is to monitor only a specefic namespace which called default and just my own pods excluding prometheus Pods and monitoring details.

I tried to specify the namespace in the kubernetes_sd_configs like this:

kubernetes_sd_configs:
        - role: endpoints
          namespaces:
            names:
            - 'default'

Buit I still getting metrics that I don't need.

Here is my configMap.yml:

apiVersion: v1
kind: ConfigMap
metadata:
  name: prometheus-server-conf
  labels:
    name: prometheus-server-conf
  namespace: default
data:
  prometheus.rules: |-
    groups:
    - name: devopscube demo alert
      rules:
      - alert: High Pod Memory
        expr: sum(container_memory_usage_bytes) > 1
        for: 1m
        labels:
          severity: slack
        annotations:
          summary: High Memory Usage
  prometheus.yml: |-
    global:
      scrape_interval: 5s
      evaluation_interval: 5s
    rule_files:
      - /etc/prometheus/prometheus.rules
    alerting:
      alertmanagers:
      - scheme: http
        static_configs:
        - targets:
          - "alertmanager.monitoring.svc:9093"

    scrape_configs:
      - job_name: 'kubernetes-apiservers'

        kubernetes_sd_configs:
        - role: endpoints
          namespaces:
            names:
            - 'default'
        scheme: https

        tls_config:
          ca_file: /var/run/secrets/kubernetes.io/serviceaccount/ca.crt
        bearer_token_file: /var/run/secrets/kubernetes.io/serviceaccount/token

        relabel_configs:
        - source_labels: [__meta_kubernetes_namespace, __meta_kubernetes_service_name, __meta_kubernetes_endpoint_port_name]
          action: keep
          regex: default;kubernetes;https

      - job_name: 'kubernetes-nodes'

        scheme: https

        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
          namespaces:
            names:
            - 'default'

        relabel_configs:
        - action: labelmap
          regex: __meta_kubernetes_node_label_(.+)
        - target_label: __address__
          replacement: kubernetes.default.svc:443
        - source_labels: [__meta_kubernetes_node_name]
          regex: (.+)
          target_label: __metrics_path__
          replacement: /api/v1/nodes/${1}/proxy/metrics


      - job_name: 'kubernetes-pods'

        kubernetes_sd_configs:
        - role: pod
          namespaces:
            names:
            - 'default'

        relabel_configs:
        - source_labels: [__meta_kubernetes_pod_annotation_prometheus_io_scrape]
          action: keep
          regex: true
        - source_labels: [__meta_kubernetes_pod_annotation_prometheus_io_path]
          action: replace
          target_label: __metrics_path__
          regex: (.+)
        - source_labels: [__address__, __meta_kubernetes_pod_annotation_prometheus_io_port]
          action: replace
          regex: ([^:]+)(?::\d+)?;(\d+)
          replacement: $1:$2
          target_label: __address__
        - action: labelmap
          regex: __meta_kubernetes_pod_label_(.+)
        - source_labels: [__meta_kubernetes_namespace]
          action: replace
          target_label: kubernetes_namespace
        - source_labels: [__meta_kubernetes_pod_name]
          action: replace
          target_label: kubernetes_pod_name

      - job_name: 'kube-state-metrics'
        static_configs:
          - targets: ['kube-state-metrics.kube-system.svc.cluster.local:8080']

      - job_name: 'kubernetes-cadvisor'

        scheme: https

        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
          namespaces:
            names:
            - 'default'

        relabel_configs:
        - action: labelmap
          regex: __meta_kubernetes_node_label_(.+)
        - target_label: __address__
          replacement: kubernetes.default.svc:443
        - source_labels: [__meta_kubernetes_node_name]
          regex: (.+)
          target_label: __metrics_path__
          replacement: /api/v1/nodes/${1}/proxy/metrics/cadvisor

      - job_name: 'kubernetes-service-endpoints'

        kubernetes_sd_configs:
        - role: endpoints
          namespaces:
            names:
            - 'default'

        relabel_configs:
        - source_labels: [__meta_kubernetes_service_annotation_prometheus_io_scrape]
          action: keep
          regex: true
        - source_labels: [__meta_kubernetes_service_annotation_prometheus_io_scheme]
          action: replace
          target_label: __scheme__
          regex: (https?)
        - source_labels: [__meta_kubernetes_service_annotation_prometheus_io_path]
          action: replace
          target_label: __metrics_path__
          regex: (.+)
        - source_labels: [__address__, __meta_kubernetes_service_annotation_prometheus_io_port]
          action: replace
          target_label: __address__
          regex: ([^:]+)(?::\d+)?;(\d+)
          replacement: $1:$2
        - action: labelmap
          regex: __meta_kubernetes_service_label_(.+)
        - source_labels: [__meta_kubernetes_namespace]
          action: replace
          target_label: kubernetes_namespace
        - source_labels: [__meta_kubernetes_service_name]
          action: replace
          target_label: kubernetes_name

I don't want to this details below for example to be monitored:

✔container_memory_rss{beta_kubernetes_io_arch="amd64",beta_kubernetes_io_os="linux",id="/system.slice/kubelet.service",instance="minikube",job="kubernetes-cadvisor",kubernetes_io_arch="amd64",kubernetes_io_hostname="minikube",kubernetes_io_os="linux"}
✔container_memory_rss{beta_kubernetes_io_arch="amd64",beta_kubernetes_io_os="linux",id="/system.slice/docker.service",instance="minikube",job="kubernetes-cadvisor",kubernetes_io_arch="amd64",kubernetes_io_hostname="minikube",kubernetes_io_os="linux"}
✔container_memory_rss{beta_kubernetes_io_arch="amd64",beta_kubernetes_io_os="linux",id="/kubepods/podda7b74d8-b611-4dff-885c-70ea40091b7d",instance="minikube",job="kubernetes-cadvisor",kubernetes_io_arch="amd64",kubernetes_io_hostname="minikube",kubernetes_io_os="linux",namespace="kube-system",pod="default-http-backend-59f7ff8999-ktqnl",pod_name="default-http-backend-59f7ff8999-ktqnl"}

Answer 1

If you just want to prevent certain metrics from being ingested (i.e. prevent from being saved in the Prometheus database), you can use metric relabelling to drop them:

  - job_name: kubernetes-cadvisor
      metric_relabel_configs:
        - source_labels: [__name__]
          regex: container_memory_rss
          action: drop

Note that in the kubernetes-cadvisor job you use the node service discovery role. This discovers Kubernetes nodes, which are non-namespaced resources, so your namespace restriction to default might not have any effect in this case.

Answer 2

Hey just found this in the docs

# Optional namespace discovery. If omitted, all namespaces are used.
namespaces:
  names:
    [ - <string> ]

right under https://prometheus.io/docs/prometheus/latest/configuration/configuration/#ingress

Answer 3

If you want to scrape metrics from a specific application or service, then apply the prometheus scrape annotations to only those application services that you are interested in.

sample

apiVersion: apps/v1beta2 # for versions before 1.8.0 use extensions/v1beta1
kind: DaemonSet
metadata:
  name: fluentd-elasticsearch
  namespace: weave
  labels:
    app: fluentd-logging
spec:
  selector:
    matchLabels:
      name: fluentd-elasticsearch
  template:
    metadata:
      labels:
        name: fluentd-elasticsearch
      annotations:
        prometheus.io/scrape: 'true'
        prometheus.io/port: '9102'
    spec:
      containers:
      - name: fluentd-elasticsearch
        image: gcr.io/google-containers/fluentd-elasticsearch:1.20

Annotations on pods allow you to control if the metrics need to be scraped or not

prometheus.io/scrape: The default configuration will scrape all pods and, if set to false, this annotation will exclude the pod from the scraping process.

prometheus.io/path: If the metrics path is not /metrics, define it with this annotation.

prometheus.io/port: Scrape the pod on the indicated port instead of the pod’s declared ports (default is a port-free target if none are declared).

Answer 4

Your configuration works only with Prometheus Operator.