Kubernetes : Metrics Server の設定2025/01/27

Metrics Server を設定して、Kubernetes クラスターの CPU/メモリーリソースのメトリクスを収集/監視します。

当例では以下のように 4 台のノードを使用して Kubernetes クラスターを構成しています。

+----------------------+   +----------------------+
|  [ ctrl.srv.world ]  |   |   [ dlp.srv.world ]  |
|     Manager Node     |   |     Control Plane    |
+-----------+----------+   +-----------+----------+
        eth0|10.0.0.25             eth0|10.0.0.30
            |                          |
------------+--------------------------+-----------
            |                          |
        eth0|10.0.0.51             eth0|10.0.0.52
+-----------+----------+   +-----------+----------+
| [ node01.srv.world ] |   | [ node02.srv.world ] |
|     Worker Node#1    |   |     Worker Node#2    |
+----------------------+   +----------------------+

[1]	Metrics Server を設定します。

[centos@ctrl ~]$

git clone https://github.com/kubernetes-sigs/metrics-server

[centos@ctrl ~]$

vi ./metrics-server/manifests/base/deployment.yaml

.....
.....
      containers:
      - name: metrics-server
        image: gcr.io/k8s-staging-metrics-server/metrics-server:master
        imagePullPolicy: IfNotPresent
        args:
          - --cert-dir=/tmp
          - --secure-port=10250
          - --kubelet-preferred-address-types=InternalIP,ExternalIP,Hostname
          - --kubelet-use-node-status-port
          - --metric-resolution=15s
          # 29行目 : 追記
          - --kubelet-insecure-tls

[centos@ctrl ~]$

kubectl apply -k ./metrics-server/manifests/base/

# Warning: 'commonLabels' is deprecated. Please use 'labels' instead. Run 'kustomize edit fix' to update your Kustomization automatically.
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

[centos@ctrl ~]$

kubectl get pods -n kube-system

NAME                                    READY   STATUS    RESTARTS   AGE
coredns-668d6bf9bc-66txn                1/1     Running   1          22h
coredns-668d6bf9bc-ph45c                1/1     Running   1          22h
etcd-dlp.srv.world                      1/1     Running   2          22h
kube-apiserver-dlp.srv.world            1/1     Running   2          22h
kube-controller-manager-dlp.srv.world   1/1     Running   2          22h
kube-proxy-4sfs2                        1/1     Running   1          22h
kube-proxy-dhcf9                        1/1     Running   1          22h
kube-proxy-wb2jd                        1/1     Running   1          22h
kube-scheduler-dlp.srv.world            1/1     Running   2          22h
metrics-server-789dc499fd-hk2cd         1/1     Running   0          78s
# [metrics-server] pod が新規にデプロイされる

[2]	CPU やメモリーの使用状況は以下のように確認できます。

[centos@ctrl ~]$

kubectl top node

NAME               CPU(cores)   CPU(%)   MEMORY(bytes)   MEMORY(%)
dlp.srv.world      78m          0%       2374Mi          15%
node01.srv.world   32m          0%       1050Mi          6%
node02.srv.world   22m          0%       1021Mi          6%

[centos@ctrl ~]$

kubectl top pod -n kube-system

NAME                                    CPU(cores)   MEMORY(bytes)
coredns-668d6bf9bc-66txn                1m           16Mi
coredns-668d6bf9bc-ph45c                1m           73Mi
etcd-dlp.srv.world                      9m           120Mi
kube-apiserver-dlp.srv.world            31m          472Mi
kube-controller-manager-dlp.srv.world   7m           151Mi
kube-proxy-4sfs2                        1m           93Mi
kube-proxy-dhcf9                        1m           93Mi
kube-proxy-wb2jd                        1m           93Mi
kube-scheduler-dlp.srv.world            4m           89Mi
metrics-server-789dc499fd-hk2cd         2m           20Mi