Project description:

Metrics Server collects resource metrics from Kubelets and exposes them in Kubernetes apiserver through Metrics API for use by Horizontal Pod Autoscaler and Vertical Pod Autoscaler.

But why not use these metrics to create alerts with alertmanager or to visualize resource usage with grafana?

is based on Metrics Server description but skips the next paragraph:

Metrics Server is not meant for non-autoscaling purposes. For example, don't use it to forward metrics to monitoring solutions, or as a source of monitoring solution metrics.

Kubelets in version 1.18+ have endpoint /metrics/resource which exposes same resource usage metrics as exposed by Metrics Server, but with improvement of being cumulative metrics instead of average load from last 15s. This means that you can collect them at higher resolution and calculate more accurate usage.

I'm trying to expose to NodePort, so I can scrape outside k8s cluster, I try this service but NodePort url not working

apiVersion: v1
kind: Service
metadata:
name: metrics-server-exporter
labels:
app: metrics-server-exporter
spec:
type: NodePort
ports:

• port: 80
  protocol: TCP
  targetPort: 8080
  nodePort: 31003
  selector:
  app: metrics-server-exporter

Good morning

I did deploy the node-exporter inside the AKS Cluster with the Cluster IP configuration for my load balancer.
If I test from another pod, the result is ok, example:

curl http://metrics-server-exporter.kube-system.svc.cluster.local:8080/metrics

HELP go_gc_duration_seconds A summary of the pause duration of garbage collection cycles.

TYPE go_gc_duration_seconds summary

go_gc_duration_seconds{quantile="0"} 8.279e-06
go_gc_duration_seconds{quantile="0.25"} 1.005e-05
go_gc_duration_seconds{quantile="0.5"} 3.6797e-05
go_gc_duration_seconds{quantile="0.75"} 7.3091e-05
go_gc_duration_seconds{quantile="1"} 0.000105625

But, I I test from my computer with curl command, I receveid 404

(I change URI for metrics-k8s in backend conf for create the isolation)

curl -v http://jd-stg-k8s.aws.acesso.intra/metrics-k8s

• Trying 10.190.11.63:80...
• Connected to jd-stg-k8s.aws.acesso.intra (10.190.11.63) port 80 (#0)

GET /metrics-k8s HTTP/1.1
Host: jd-stg-k8s.aws.acesso.intra
User-Agent: curl/7.74.0
Accept: /

• Mark bundle as not supporting multiuse
  < HTTP/1.1 404 Not Found
  < Content-Type: text/plain; charset=utf-8
  < Content-Length: 19
  < Connection: keep-alive
  < X-Content-Type-Options: nosniff
  < Date: Tue, 06 Apr 2021 13:30:37 GMT
  < X-Kong-Upstream-Latency: 2
  < X-Kong-Proxy-Latency: 0
  < Via: kong/2.2.2
  <
  404 page not found
• Connection #0 to host jd-stg-k8s.aws.acesso.intra left intact

=== My yaml

apiVersion: v1
kind: List
items:

• apiVersion: apps/v1
  kind: Deployment
  metadata:
  name: metrics-server-exporter
  namespace: kube-system
  labels:
  app: metrics-server-exporter
  spec:
  replicas: 1
  strategy:
  type: RollingUpdate
  rollingUpdate:
  maxSurge: 2
  maxUnavailable: 0
  selector:
  matchLabels:
  app: metrics-server-exporter
  template:
  metadata:
  labels:
  app: metrics-server-exporter
  annotations:
  prometheus.io/path: "/metrics"
  prometheus.io/port: "8080"
  prometheus.io/scheme: "http"
  prometheus.io/scrape: "true"
  spec:
  containers:
  - name: metrics-server-exporter
  image: ghouscht/metrics-server-exporter:0.0.1
  imagePullPolicy: Always
  ports:
  - containerPort: 8080
  serviceAccountName: metrics-server-exporter
  dnsPolicy: ClusterFirst
  restartPolicy: Always
  terminationGracePeriodSeconds: 30
• kind: Service
  apiVersion: v1
  metadata:
  name: metrics-server-exporter
  namespace: kube-system
  annotations:
  spec:
  selector:
  app: metrics-server-exporter
  ports:
  - name: mainport
  port: 8080
  protocol: TCP
  targetPort: 8080
  type: ClusterIP
• apiVersion: extensions/v1beta1
  kind: Ingress
  metadata:
  name: metrics-server-exporter
  namespace: kube-system
  annotations:
  kubernetes.io/ingress.class: kong
  konghq.com/strip-path: "true"
  spec:
  rules:
  - host: jd-stg-k8s.aws.acesso.intra
  http:
  paths:
  - path: /metrics-k8s
  backend:
  serviceName: metrics-server-exporter
  servicePort: 8080
• kind: ServiceAccount
  apiVersion: v1
  metadata:
  name: metrics-server-exporter
  namespace: kube-system
• kind: ClusterRole
  apiVersion: rbac.authorization.k8s.io/v1
  metadata:
  name: metrics-server-exporter
  rules:
  • apiGroups:
    • metrics.k8s.io
      resources:
      • nodes
      • pods
        verbs:
      • list
      • get
  • apiGroups:
    • ""
      resources:
      • nodes
        verbs:
      • list
      • get
• kind: ClusterRoleBinding
  apiVersion: rbac.authorization.k8s.io/v1
  metadata:
  name: metrics-server-exporter
  roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: ClusterRole
  name: metrics-server-exporter
  subjects:
  - kind: ServiceAccount
  name: metrics-server-exporter
  namespace: kube-system