Ubuntu(20.04LTS) + Kubernetes(v1.21.3)にmetrics-serverをインストール

#設定

基本はgithubのページの通りに設定していく。
一部追記が必要なため、yamlをダウンロードする。

$ wget https://github.com/kubernetes-sigs/metrics-server/releases/latest/download/components.yaml

components.yaml

---
apiVersion: apps/v1
kind: Deployment
metadata:
  labels:
    k8s-app: metrics-server
  name: metrics-server
  namespace: kube-system
spec:
  selector:
    matchLabels:
      k8s-app: metrics-server
  strategy:
    rollingUpdate:
      maxUnavailable: 0
  template:
    metadata:
      labels:
        k8s-app: metrics-server
    spec:
      containers:
      - args:
        - --cert-dir=/tmp
        - --secure-port=443
        - --kubelet-preferred-address-types=InternalIP,ExternalIP,Hostname
        - --kubelet-use-node-status-port
        - --metric-resolution=15s
        image: k8s.gcr.io/metrics-server/metrics-server:v0.5.0
        imagePullPolicy: IfNotPresent
+        command:
+        - /metrics-server
+        - --kubelet-insecure-tls
+        - --kubelet-preferred-address-types=InternalIP

#適用

$ kubectl apply -f components.yaml
serviceaccount/metrics-server created
clusterrole.rbac.authorization.k8s.io/system:aggregated-metrics-reader created
clusterrole.rbac.authorization.k8s.io/system:metrics-server created
rolebinding.rbac.authorization.k8s.io/metrics-server-auth-reader created
clusterrolebinding.rbac.authorization.k8s.io/metrics-server:system:auth-delegator created
clusterrolebinding.rbac.authorization.k8s.io/system:metrics-server created
service/metrics-server created
deployment.apps/metrics-server created
apiservice.apiregistration.k8s.io/v1beta1.metrics.k8s.io created

#メトリクス収集確認

$ kubectl -n kube-system top pods
W0815 23:53:59.483427  528625 top_pod.go:140] Using json format to get metrics. Next release will switch to protocol-buffers, switch early by passing --use-protocol-buffers flag
NAME                                       CPU(cores)   MEMORY(bytes)
calico-kube-controllers-58497c65d5-gjbqc   4m           24Mi
calico-node-pkpbv                          65m          141Mi
coredns-558bd4d5db-8qbv7                   6m           16Mi
coredns-558bd4d5db-qfr55                   6m           15Mi
etcd-xxxxccc                               38m          46Mi
kube-apiserver-caltagx                     103m         479Mi
kube-controller-manager-caltagx            23m          63Mi
kube-proxy-d68mn                           1m           31Mi
kube-scheduler-caltagx                     5m           23Mi
metrics-server-6468fcbb58-kf7mc            5m           19Mi