K8S部署Metrics-Server服务

1.下载并解压Metrics-Server
https://github.com/kubernetes-sigs/metrics-server/archive/v0.3.6.tar.gz
tar -zxvf v0.3.6.tar.gz
2.修改Metrics-Server配置文件
cd metrics-server-0.3.6/deploy/1.8+/
vim metrics-server-deployment.yaml

vim metrics-server-deployment.yaml文件（修改后的）

---
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-insecure-tls
        - --kubelet-preferred-address-types=InternalDNS,InternalIP,ExternalDNS,ExternalIP,Hostname
        volumeMounts:
        - name: tmp-dir
          mountPath: /tmp
        resources:
          limits:
            cpu: 300m
            memory: 200Mi
          requests:
            cpu: 200m
            memory: 100Mi

　　

3.安装Metrics-Server
kubectl apply -f metrics-server-0.3.6/deploy/1.8+/
4.查看node信息
[root@master 1.8+]# kubectl top node
NAME CPU(cores) CPU% MEMORY(bytes) MEMORY%
master 289m 7% 1315Mi 48%
node01 119m 2% 910Mi 33%
node02 100m 2% 628Mi 23%
5、测试HPA
1）、创建部署deployment，这里设置副本数是1

apiVersion: v1
kind: Service
metadata:
  name: svc-hpa
  namespace: default
spec:
  selector:
    app: nginx
  type: NodePort  ##注意这里是NodePort，下面压力测试要用到。
  ports:
  - name: http
    port: 80
---
apiVersion: apps/v1
kind: Deployment
metadata:
  name: nginx-deployment
spec:
  replicas: 1
  selector:
     matchLabels:
       app: nginx
  template:
    metadata:
      labels:
        app: nginx
    spec:
      containers:
      - name: nginx
        image: docker.io/nginx
        ports:
        - containerPort: 80
        resources:
          limits:
             cpu: 50m
             memory: 50Mi
          requests:
             cpu: 50m
             memory: 50Mi

　　

2)、设定自动扩容的条件

kubectl autoscale deployment nginx-deployment --max=3 --min=1 --cpu-percent=50
使用ab工具进行压测

先安装ab

yum -y install httpd-tools -y
3）、使用ab工具进行压测

ab -c 500 -n 2000 http://192.168.111.129:31379/
发现副本成两个了

[root@master test]# kubectl get pod
NAME READY STATUS RESTARTS AGE
nginx-deployment-859b474bd-2nnlv 1/1 Running 0 60m
nginx-deployment-859b474bd-pfm4l 1/1 Running 0 4m38s
过一段时间又变成了一个

[root@master test]# kubectl get pod
NAME READY STATUS RESTARTS AGE
nginx-deployment-859b474bd-2nnlv 1/1 Running 0 61m
nginx-deployment-859b474bd-pfm4l 0/1 Terminating 0 5m23s
[root@master test]# kubectl get pod
NAME READY STATUS RESTARTS AGE
nginx-deployment-859b474bd-2nnlv 1/1 Running 0 61m
看下hpa

[root@master test]# kubectl get hpa
NAME REFERENCE TARGETS MINPODS MAXPODS REPLICAS AGE
nginx-deployment Deployment/nginx-deployment 10%/50% 1 3 1 50m