k8s下安装metrics-server

环境:
OS:Centos 7
k8s:1.24.0

 

1.部署了hpa后发现无法获取指标数据

[root@master hpa]# kubectl describe hpa nginx-deployment-hpa -n ns-hpa
Warning: autoscaling/v2beta2 HorizontalPodAutoscaler is deprecated in v1.23+, unavailable in v1.26+; use autoscaling/v2 HorizontalPodAutoscaler
Name:                                                  nginx-deployment-hpa
Namespace:                                             ns-hpa
Labels:                                                <none>
Annotations:                                           <none>
CreationTimestamp:                                     Wed, 09 Apr 2025 17:20:38 +0800
Reference:                                             Deployment/nginx-deployment
Metrics:                                               ( current / target )
  resource cpu on pods  (as a percentage of request):  <unknown> / 50%
Min replicas:                                          1
Max replicas:                                          10
Deployment pods:                                       1 current / 0 desired
Conditions:
  Type           Status  Reason                   Message
  ----           ------  ------                   -------
  AbleToScale    True    SucceededGetScale        the HPA controller was able to get the target's current scale
  ScalingActive  False   FailedGetResourceMetric  the HPA was unable to compute the replica count: failed to get cpu utilization: unable to get metrics for resource cpu: unable to fetch metrics from resource metrics API: the server could not find the requested resource (get pods.metrics.k8s.io)
Events:
  Type     Reason                   Age                       From                       Message
  ----     ------                   ----                      ----                       -------
  Warning  FailedGetResourceMetric  2m37s (x1140 over 4h47m)  horizontal-pod-autoscaler  failed to get cpu utilization: unable to get metrics for resource cpu: unable to fetch metrics from resource metrics API: the server could not find the requested resource (get pods.metrics.k8s.io)
  

the HPA was unable to compute the replica count: failed to get cpu utilization: unable to get metrics for resource cpu: unable to fetch metrics from resource metrics API: the server could not find the requested resource (get pods.metrics.k8s.io)

 

[root@master hpa]# kubectl get hpa -n ns-hpa
NAME                   REFERENCE                     TARGETS         MINPODS   MAXPODS   REPLICAS   AGE
nginx-deployment-hpa   Deployment/nginx-deployment   <unknown>/50%   1         10        1          39s

 

2.需要安装metrics-server

获取yaml配置文件
wget https://github.com/kubernetes-sigs/metrics-server/releases/latest/download/components.yaml
重命名
mv components.yaml metrics-server.yaml

修改镜像为阿里云镜像

image: registry.cn-hangzhou.aliyuncs.com/google_containers/metrics-server:v0.7.2

 

应用
kubectl apply -f metrics-server.yaml

 

 

3.发现包如下错误

Readiness probe failed: HTTP probe failed with statuscode: 500

解决办法：

解决办法:
kubectl delete -f metrics-server.yaml

vi metrics-server.yaml

在如图所示添加 - --kubelet-insecure-tls

 

重新应用
kubectl apply -f metrics-server.yaml

 

4.查看

[root@master hpa]# kubectl top pod -A
NAMESPACE         NAME                                             CPU(cores)   MEMORY(bytes)   
cert-manager      cert-manager-bcc6fc947-g4jvd                     1m           22Mi            
cert-manager      cert-manager-cainjector-74b489f78f-pmh8m         1m           24Mi            
cert-manager      cert-manager-webhook-68dc7956b4-n2j4j            1m           17Mi            
kube-system       calico-kube-controllers-6b668cd977-lv54j         2m           22Mi            
kube-system       calico-node-gpdrp                                21m          105Mi           
kube-system       calico-node-klbrm                                17m          124Mi           
kube-system       calico-node-vtmch                                34m          128Mi           
kube-system       coredns-c676cc86f-6rrp4                          2m           18Mi            
kube-system       coredns-c676cc86f-pjl52                          1m           16Mi            
kube-system       etcd-master                                      24m          122Mi           
kube-system       kube-apiserver-master                            55m          463Mi           
kube-system       kube-controller-manager-master                   19m          64Mi            
kube-system       kube-proxy-ptb4h                                 1m           22Mi            
kube-system       kube-proxy-v6b8x                                 1m           19Mi            
kube-system       kube-proxy-xjmxk                                 1m           17Mi            
kube-system       kube-scheduler-master                            3m           22Mi            
kube-system       metrics-server-7667bfbfbb-vrn6z                  5m           18Mi            
middleware        milvus-dev-milvus-datanode-555c8859fc-nqdjw      20m          100Mi           
middleware        milvus-dev-milvus-indexnode-68f89cbb65-bj6p8     4m           113Mi           
middleware        milvus-dev-milvus-mixcoord-5879ddb6bf-zq5qb      43m          204Mi           
middleware        milvus-dev-milvus-proxy-6d7656657f-pwm29         26m          132Mi           
middleware        milvus-dev-milvus-querynode-0-5cd5fb96b6-j5xzc   18m          150Mi           
milvus-operator   milvus-operator-75bccd859c-gxj2j                 3m           30Mi            
ns-hpa            nginx-deployment-cb5988cbd-tchrh                 0m           3Mi             
ns-mysql          hxl-mysql-deploy-5c579f8d6f-qp55t                1m           212Mi           
velero            velero-75cd89cf9b-fjvcw                          3m           31Mi     

 

[root@master hpa]# kubectl top nodes
NAME     CPU(cores)   CPU%   MEMORY(bytes)   MEMORY%   
master   332m         16%    2657Mi          46%       
node1    112m         11%    1412Mi          24%       
node2    189m         9%     3322Mi          57%