kubernetes集群编排（8）

目录

k8s资源监控

资源限制

limitrange

ResourceQuota

metrics-server

dashboard

k9s

hpa

k8s资源监控

资源限制

[root@k8s2 limit]# vim limit.yaml
apiVersion: v1
kind: Pod
metadata:
  name: memory-demo
spec:
  containers:
  - name: memory-demo
    image: stress
    args:
    - --vm
    - "1"
    - --vm-bytes
    - 200M
    resources:
      requests:
        memory: 50Mi
      limits:
        memory: 100Mi

limitrange

[root@k8s2 limit]# cat range.yaml
apiVersion: v1
kind: LimitRange
metadata:
  name: limitrange-memory
spec:
  limits:
  - default:
      cpu: 0.5
      memory: 512Mi
    defaultRequest:
      cpu: 0.1
      memory: 256Mi
    max:
      cpu: 1
      memory: 1Gi
    min:
      cpu: 0.1
      memory: 100Mi
    type: Container

[root@k8s2 limit]# kubectl apply -f range.yaml
[root@k8s2 limit]# kubectl describe limitrange

创建的pod自动添加限制

自定义限制的pod也需要在limitrange定义的区间内

ResourceQuota

[root@k8s2 limit]# vim range.yaml
apiVersion: v1
kind: LimitRange
metadata:
  name: limitrange-memory
spec:
  limits:
  - default:
      cpu: 0.5
      memory: 512Mi
    defaultRequest:
      cpu: 0.1
      memory: 256Mi
    max:
      cpu: 1
      memory: 1Gi
    min:
      cpu: 0.1
      memory: 100Mi
    type: Container
 
 
---
apiVersion: v1
kind: ResourceQuota
metadata:
  name: mem-cpu-demo
spec:
  hard:
    requests.cpu: "1"
    requests.memory: 1Gi
    limits.cpu: "2"
    limits.memory: 2Gi
    pods: "2"

配额是针对namespace施加的总限额，命名空间内的所有pod资源总和不能超过此配额

创建的pod必须定义资源限制

metrics-server

下载部署文件

[root@k8s2 metrics]# wget https://github.com/kubernetes-sigs/metrics-server/releases/latest/download/components.yaml

[root@k8s2 metrics]# kubectl apply -f components.yaml
[root@k8s2 metrics]# kubectl -n kube-system get pod

[root@k8s2 metrics]# kubectl -n kube-system logs metrics-server-5d54764497-8vjm5

[root@k8s2 metrics]# kubectl top node
[root@k8s2 metrics]# kubectl top pod -A --sort-by cpu

上传所需镜像到harbor

修改svc为loadbalancer

[root@k8s2 dashboard]# kubectl apply -f recommended.yaml
[root@k8s2 dashboard]# kubectl -n kubernetes-dashboard edit svc kubernetes-dashboard

[root@k8s2 dashboard]# vim rbac.yaml
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRoleBinding
metadata:
  name: admin-user
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: ClusterRole
  name: cluster-admin
subjects:
- kind: ServiceAccount
  name: kubernetes-dashboard
  namespace: kubernetes-dashboard

[root@k8s2 dashboard]# kubectl apply -f rbac.yaml
[root@k8s2 dashboard]# kubectl -n kubernetes-dashboard create token kubernetes-dashboard

使用token登录网页

hpa

官网：HorizontalPodAutoscaler 演练 | Kubernetes

上传镜像

[root@k8s2 hpa]# vim hpa.yaml
apiVersion: apps/v1
kind: Deployment
metadata:
  name: php-apache
spec:
  selector:
    matchLabels:
      run: php-apache
  replicas: 1
  template:
    metadata:
      labels:
        run: php-apache
    spec:
      containers:
      - name: php-apache
        image: hpa-example
        ports:
        - containerPort: 80
        resources:
          limits:
            cpu: 500m
          requests:
            cpu: 200m
---
apiVersion: v1
kind: Service
metadata:
  name: php-apache
  labels:
    run: php-apache
spec:
  ports:
  - port: 80
  selector:
    run: php-apache

[root@k8s2 hpa]# kubectl apply -f hpa.yaml
[root@k8s2 hpa]# kubectl autoscale deployment php-apache --cpu-percent=50 --min=1 --max=10
//当 CPU 利用率超过 50% 时，HPA 将根据当前 CPU 利用率来动态地扩展 Deployment 的副本数，使其保持在 1 到 10 之间
[root@k8s2 hpa]# kubectl get hpa

压测

[root@k8s2 hpa]# kubectl run -i --tty load-generator --rm --image=busybox --restart=Never -- /bin/sh -c "while sleep 0.01; do wget -q -O- http://php-apache; done"

pod负载上升

结束压测后，默认等待5分钟冷却时间，pod会被自动回收

多项量度指标

[root@k8s2 hpa]# kubectl get hpa php-apache -o yaml > hpa-v2.yaml

  - resource:
      name: memory
      target:
        averageValue: 50Mi
        type: AverageValue
    type: Resource

[root@k8s2 hpa]# kubectl apply -f hpa-v2.yaml
 
[root@k8s2 hpa]# kubectl get hpa