【k8s】部署metrics-server

实验环境

kubernetes: 1.18.0

dokcer：Docker version 20.10.18, build b40c2f6

部署步骤

1，执行yaml文件

kubectl apply -f metrics-server.yaml

metrics-server.yaml

---
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRole
metadata:
  name: system:aggregated-metrics-reader
  labels:
    rbac.authorization.k8s.io/aggregate-to-view: "true"
    rbac.authorization.k8s.io/aggregate-to-edit: "true"
    rbac.authorization.k8s.io/aggregate-to-admin: "true"
rules:
- apiGroups: ["metrics.k8s.io"]
  resources: ["pods", "nodes"]
  verbs: ["get", "list", "watch"]
---
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRoleBinding
metadata:
  name: metrics-server:system:auth-delegator
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: ClusterRole
  name: system:auth-delegator
subjects:
- kind: ServiceAccount
  name: metrics-server
  namespace: kube-system
---
apiVersion: rbac.authorization.k8s.io/v1
kind: RoleBinding
metadata:
  name: metrics-server-auth-reader
  namespace: kube-system
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: Role
  name: extension-apiserver-authentication-reader
subjects:
- kind: ServiceAccount
  name: metrics-server
  namespace: kube-system
---
apiVersion: apiregistration.k8s.io/v1beta1
kind: APIService
metadata:
  name: v1beta1.metrics.k8s.io
spec:
  service:
    name: metrics-server
    namespace: kube-system
  group: metrics.k8s.io
  version: v1beta1
  insecureSkipTLSVerify: true
  groupPriorityMinimum: 100
  versionPriority: 100
---
apiVersion: v1
kind: ServiceAccount
metadata:
  name: metrics-server
  namespace: kube-system
---
apiVersion: apps/v1
kind: Deployment
metadata:
  name: metrics-server
  namespace: kube-system
  labels:
    k8s-app: metrics-server
spec:
  selector:
    matchLabels:
      k8s-app: metrics-server
  template:
    metadata:
      name: metrics-server
      labels:
        k8s-app: metrics-server
    spec:
      serviceAccountName: metrics-server
      volumes:
      # mount in tmp so we can safely use from-scratch images and/or read-only containers
      - name: tmp-dir
        emptyDir: {}
      containers:
      - name: metrics-server
        image: mirrorgooglecontainers/metrics-server-amd64:v0.3.6
        imagePullPolicy: IfNotPresent
        command:
        - /metrics-server
        - --kubelet-preferred-address-types=InternalIP
        - --kubelet-insecure-tls
        - --v=2
        args:
          - --cert-dir=/tmp
          - --secure-port=4443
        ports:
        - name: main-port
          containerPort: 4443
          protocol: TCP
        securityContext:
          readOnlyRootFilesystem: true
          runAsNonRoot: true
          runAsUser: 1000
        volumeMounts:
        - name: tmp-dir
          mountPath: /tmp
      nodeSelector:
        kubernetes.io/os: linux
        kubernetes.io/arch: "amd64"
---
apiVersion: v1
kind: Service
metadata:
  name: metrics-server
  namespace: kube-system
  labels:
    kubernetes.io/name: "Metrics-server"
    kubernetes.io/cluster-service: "true"
spec:
  selector:
    k8s-app: metrics-server
  ports:
  - port: 443
    protocol: TCP
    targetPort: main-port
---
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRole
metadata:
  name: system:metrics-server
rules:
- apiGroups:
  - ""
  resources:
  - pods
  - nodes
  - nodes/stats
  - namespaces
  - configmaps
  verbs:
  - get
  - list
  - watch
---
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRoleBinding
metadata:
  name: system:metrics-server
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: ClusterRole
  name: system:metrics-server
subjects:
- kind: ServiceAccount
  name: metrics-server
  namespace: kube-system

关键点说明：

1，镜像地址改为mirrorgooglecontainers/metrics-server-amd64:v0.3.6，使用了dokcerhub的镜像，解决国内访问不到google镜像问题。

2，增加了三个command参数，分别解决了三个问题：

--kubelet-preferred-address-types=InternalIP

解决这个问题

unable to fully collect metrics: unable to fully scrape metrics from source kubelet_summary:localhost.localdomain: unable to fetch metrics from Kubelet localhost.localdomain (localhost.localdomain): Get https://localhost.localdomain:10250/stats/summary?only_cpu_and_memory=true: dial tcp: lookup localhost.localdomain on 172.31.2.1:53: no such host

--kubelet-insecure-tls

解决了这个问题

unable to fully collect metrics: unable to fully scrape metrics from source kubelet_summary:localhost.localdomain: unable to fetch metrics from Kubelet localhost.localdomain (10.0.2.15): Get https://10.0.2.15:10250/stats/summary?only_cpu_and_memory=true: x509: cannot validate certificate for 10.0.2.15 because it doesn't contain any IP SANs

--v=2

解决了这个问题

unable to fetch pod metrics for pod default/nginx-7d5886d785-w7sg2: no metrics known for pod