Monitoring Master Node Components Using Prometheus

Collecting the Metrics of Master Node Components Using Self-Built Prometheus

1. Use kubectl to connect to the cluster.
2. Modify the ClusterRole of Prometheus.

   kubectl edit ClusterRole prometheus -n {namespace}
   
   

   Add the following content under the rules field:

   rules:
   ...
   - apiGroups:
     - proxy.exporter.k8s.io
     resources:
     - "*"
     verbs: ["get", "list", "watch"]
   
   

3. Create a file named kube-apiserver.yaml and edit it.

   vi kube-apiserver.yaml
   
   

   Example file content:

   apiVersion: monitoring.coreos.com/v1
   kind: ServiceMonitor
   metadata:
     labels:
       app.kubernetes.io/name: apiserver
     name: kube-apiserver
     namespace: monitoring    # Change it to the namespace where Prometheus will be installed.
   spec:
     endpoints:
     - bearerTokenFile: /var/run/secrets/kubernetes.io/serviceaccount/token
       interval: 30s
       metricRelabelings:
       - action: keep
         regex: (aggregator_unavailable_apiservice|apiserver_admission_controller_admission_duration_seconds_bucket|apiserver_admission_webhook_admission_duration_seconds_bucket|apiserver_admission_webhook_admission_duration_seconds_count|apiserver_client_certificate_expiration_seconds_bucket|apiserver_client_certificate_expiration_seconds_count|apiserver_current_inflight_requests|apiserver_request_duration_seconds_bucket|apiserver_request_total|go_goroutines|kubernetes_build_info|process_cpu_seconds_total|process_resident_memory_bytes|rest_client_requests_total|workqueue_adds_total|workqueue_depth|workqueue_queue_duration_seconds_bucket|aggregator_unavailable_apiservice_total|rest_client_request_duration_seconds_bucket)
         sourceLabels:
         - __name__
       - action: drop
         regex: apiserver_request_duration_seconds_bucket;(0.15|0.25|0.3|0.35|0.4|0.45|0.6|0.7|0.8|0.9|1.25|1.5|1.75|2.5|3|3.5|4.5|6|7|8|9|15|25|30|50)
         sourceLabels:
         - __name__
         - le
       port: https
       scheme: https
       tlsConfig:
         caFile: /var/run/secrets/kubernetes.io/serviceaccount/ca.crt
         serverName: kubernetes
     jobLabel: component
     namespaceSelector:
       matchNames:
       - default
     selector:
       matchLabels:
         component: apiserver
         provider: kubernetes
   
   

   Create a ServiceMonitor:

   kubectl apply -f kube-apiserver.yaml
   
   

4. Create a file named kube-controller.yaml and edit it.

   vi kube-controller.yaml
   
   

   Example file content:

   apiVersion: monitoring.coreos.com/v1
   kind: ServiceMonitor
   metadata:
     labels:
       app.kubernetes.io/name: kube-controller
     name: kube-controller-manager
     namespace: monitoring    # Change it to the namespace where Prometheus will be installed.
   spec:
     endpoints:
       - bearerTokenFile: /var/run/secrets/kubernetes.io/serviceaccount/token
         interval: 15s
         honorLabels: true
         port: https
         relabelings:
           - regex: (.+)
             replacement: /apis/proxy.exporter.k8s.io/v1beta1/kube-controller-proxy/${1}/metrics
             sourceLabels:
               - __address__
             targetLabel: __metrics_path__
           - regex: (.+)
             replacement: ${1}
             sourceLabels:
               - __address__
             targetLabel: instance
           - replacement: kubernetes.default.svc.cluster.local:443
             targetLabel: __address__
         scheme: https
         tlsConfig:
           caFile: /var/run/secrets/kubernetes.io/serviceaccount/ca.crt
     jobLabel: app
     namespaceSelector:
       matchNames:
         - kube-system
     selector:
       matchLabels:
         app: kube-controller-proxy
         version: v1
   
   

   Create a ServiceMonitor:

   kubectl apply -f kube-controller.yaml
   
   

5. Create a file named kube-scheduler.yaml and edit it.

   vi kube-scheduler.yaml
   
   

   Example file content:

   apiVersion: monitoring.coreos.com/v1
   kind: ServiceMonitor
   metadata:
     labels:
       app.kubernetes.io/name: kube-scheduler
     name: kube-scheduler
     namespace: monitoring    # Change it to the namespace where Prometheus will be installed.
   spec:
     endpoints:
       - bearerTokenFile: /var/run/secrets/kubernetes.io/serviceaccount/token
         interval: 15s
         honorLabels: true
         port: https
         relabelings:
           - regex: (.+)
             replacement: /apis/proxy.exporter.k8s.io/v1beta1/kube-scheduler-proxy/${1}/metrics
             sourceLabels:
               - __address__
             targetLabel: __metrics_path__
           - regex: (.+)
             replacement: ${1}
             sourceLabels:
               - __address__
             targetLabel: instance
           - replacement: kubernetes.default.svc.cluster.local:443
             targetLabel: __address__
         scheme: https
         tlsConfig:
           caFile: /var/run/secrets/kubernetes.io/serviceaccount/ca.crt
     jobLabel: app
     namespaceSelector:
       matchNames:
         - kube-system
     selector:
       matchLabels:
         app: kube-scheduler-proxy
         version: v1
   
   

   Create a ServiceMonitor:

   kubectl apply -f kube-scheduler.yaml
   
   

6. Create a file named etcd-server.yaml and edit it.

   vi etcd-server.yaml
   
   

   Example file content:

   apiVersion: monitoring.coreos.com/v1
   kind: ServiceMonitor
   metadata:
     labels:
       app.kubernetes.io/name: etcd-server
     name: etcd-server
     namespace: monitoring    # Change it to the namespace where Prometheus will be installed.
   spec:
     endpoints:
       - bearerTokenFile: /var/run/secrets/kubernetes.io/serviceaccount/token
         interval: 15s
         honorLabels: true
         port: https
         relabelings:
           - regex: (.+)
             replacement: /apis/proxy.exporter.k8s.io/v1beta1/etcd-server-proxy/${1}/metrics
             sourceLabels:
               - __address__
             targetLabel: __metrics_path__
           - regex: (.+)
             replacement: ${1}
             sourceLabels:
               - __address__
             targetLabel: instance
           - replacement: kubernetes.default.svc.cluster.local:443
             targetLabel: __address__
         scheme: https
         tlsConfig:
           caFile: /var/run/secrets/kubernetes.io/serviceaccount/ca.crt
     jobLabel: app
     namespaceSelector:
       matchNames:
         - kube-system
     selector:
       matchLabels:
         app: etcd-server-proxy
         version: v1
   
   

   Create a ServiceMonitor:

   kubectl apply -f etcd-server.yaml
   
   

7. Access Prometheus and choose Status > Targets.

   The preceding master node components are displayed.