第二十四章 Kubernetes部署metrics-server性能监控平台

一、Heapster介绍

Heapster是容器集群监控和性能分析工具，天然的支持Kubernetes和CoreOS。

Kubernetes有个出名的监控agent—cAdvisor。开源软件 cAdvisor（Container Advisor）用于监控所在节点的容器运行状态，当前已经被默认集成到 kubelet 组件内，默认使用 tcp 4194 端口。在大规模容器集群，一般使用Heapster+Influxdb+Grafana 平台实现集群性能数据的采集，存储与展示。

cAdvisor web界面访问： http://< Node-IP >:4194
cAdvisor也提供Restful API: https://github.com/google/cadvisor/blob/master/docs/api.md

二、环境原理介绍

1.基础环境

Kubernetes + heapster + Influxdb + grafana

2.原理

Heapster：集群中各 node 节点的 cAdvisor 的数据采集汇聚系统，通过调用 node 上kubelet 的 api，再通过 kubelet 调用 cAdvisor 的 api 来采集所在节点上所有容器的性能数据。Heapster 对性能数据进行聚合，并将结果保存到后端存储系统，heapster 支持多种后端存储系统，如 memory，Influxdb 等。

Influxdb：分布式时序数据库（每条记录有带有时间戳属性），主要用于实时数据采集，   时间跟踪记录，存储时间图表，原始数据等。Influxdb 提供 rest api 用于数据的存储与查询。

Grafana：通过 dashboard 将 Influxdb 中的时序数据展现成图表或曲线等形式，便于查看集群运行状态。

Heapster，Influxdb，Grafana 均以 Pod 的形式启动与运行。

三、部署 Kubernetes 集群性能监控

1.准备images

kubernetes 部署服务时，为避免部署时发生 pull 镜像超时的问题，建议提前将相关镜像pull 到相关所有节点（以下以 kubenode1 为例），或搭建本地镜像系统。

需要从 gcr.io pull 的镜像，已利用 Docker Hub 的"Create Auto-Build GitHub"功能（Docker Hub 利用 GitHub 上的 Dockerfile 文件 build 镜像），在个人的 Docker Hub build 成功，可直接 pull 到本地使用。

# heapster
[root@kubenode1 ~]# docker pull netonline/heapster-amd64:v1.5.1

# influxdb
[root@kubenode1 ~]# docker pull netonline/heapster-influxdb-amd64:v1.3.3

# grafana
[root@kubenode1 ~]# docker pull netonline/heapster-grafana-amd64:v4.4.3

2.下载 yaml 范本

# release 下载页：https://github.com/kubernetes/heapster/releases # release 中的 yaml 范本有时较https://github.com/kubernetes/heapster/tree/master/deploy/kube-config/influxdb  的 yaml 新，但区别不大

[root@kubenode1 ~]# cd /usr/local/src/ 
[root@kubenode1 src]# wget -O heapster-v1.5.1.tar.gz https://github.com/kubernetes/heapster/archive/v1.5.1.tar.gz

# yaml 范本在 heapster/deploy/kube-config/influxdb 目录，另有 1 个 heapster-rbac.yaml 在 heapster/deploy/kube-config/rbac 目录，两者目录结构同 github
[root@kubenode1 src]# tar -zxvf heapster-v1.5.1.tar.gz -C /usr/local/ 
[root@kubenode1 src]# ln -s /usr/local/heapster-1.5.1 /usr/local/heapster

3.heapster-rbac.yaml

# heapster 需要向 kubernetes-master 请求 node 列表，需要设置相应权限；
# 默认不需要对 heapster-rbac.yaml 修改，将 kubernetes 集群自带的 ClusterRole ：system:heapster 做 ClusterRoleBinding，完成授权

[root@kubenode1 ~]# cd /usr/local/heapster/deploy/kube-config/rbac/ 
[root@kubenode1 rbac]# vi heapster-rbac.yaml
kind: ClusterRoleBinding
apiVersion: rbac.authorization.k8s.io/v1
metadata:
  name: heapster
roleRef:
 apiGroup: rbac.authorization.k8s.io
 kind: ClusterRole
 name: system:heapster
subjects:
- kind: ServiceAccount
  name: heapster
  namespace: kube-system

4.heapster.yaml

hepster.yaml 由 3 个模块组成：ServiceAccout，Deployment，Service。

1）ServiceAccount
默认不需要修改 ServiceAccount 部分，设置 ServiceAccount 资源，获取 rbac 中定义的权限。

2）Deployment
# 修改处：第 23 行，变更镜像名；
# --source：配置采集源，使用安全端口调用 kubernetes 集群 api；
# --sink：配置后端存储为 influxdb；地址采用 influxdb 的 service 名，需要集群 dns 正常工作，如果没有配置 dns 服务，可使用 service 的 ClusterIP 地址
[root@kubenode1 ~]# cd /usr/local/heapster/deploy/kube-config/influxdb/
[root@kubenode1 influxdb]# sed -i 's|gcr.io/google_containers/heapster-amd64:v1.5.1|netonline/heapster-amd64:v1.5.1|g' heapster.yaml
[root@kubenode1 influxdb]# vi heapster.yaml

apiVersion: v1
kind: ServiceAccount
metadata:
  name: heapster
  namespace: kube-system
---
apiVersion: apps/v1
kind: Deployment
metadata:
  name: heapster
  namespace: kube-system
spec:
  replicas: 1
  selector:
    matchLabels:
       app: heapster
  template:
    metadata:
      labels:
        task: monitoring
        app: heapster
    spec:
      serviceAccountName: heapster
      containers:
      - name: heapster
        image: netonline/heapster-amd64:v1.5.1
        imagePullPolicy: IfNotPresent
        command:
        - /heapster
        - --source=kubernetes:https://kubernetes.default
        - --sink=influxdb:http://monitoring-influxdb.kube-system.svc:8086
---
apiVersion: v1
kind: Service
metadata:
  labels:
    task: monitoring
    # For use as a Cluster add-on (https://github.com/kubernetes/kubernetes/tree/master/cluster/addons)
    # If you are NOT using this as an addon, you should comment out this line.
    kubernetes.io/cluster-service: 'true'
    kubernetes.io/name: Heapster
  name: heapster
  namespace: kube-system
spec:
  ports:
  - port: 80
    targetPort: 8082
  selector:
    k8s-app: heapster

3）Service
默认不需要修改 Service 部分。

5.influxdb.yaml

influxdb.yaml 由 2 个模块组成：Deployment，Service。

1）Deployment
# 修改处：第 16 行，变更镜像名；
[root@kubenode1 influxdb]# sed -i 's|gcr.io/google_containers/heapster-influxdb-amd64:v1.3.3|netonline/heapster-influxdb-amd64:v1.3.3|g' influxdb.yaml
[root@kubenode1 influxdb]# vi influxdb.yaml

apiVersion: apps/v1
kind: Deployment
metadata:
  name: monitoring-influxdb
  namespace: kube-system
spec:
  replicas: 1
  selector:
    matchLabels:
      app: influxdb
  template:
    metadata:
      labels:
        task: monitoring
        app: influxdb
    spec:
      containers:
      - name: influxdb
        image: netonline/heapster-influxdb-amd64:v1.3.3
        volumeMounts:
        - mountPath: /data
          name: influxdb-storage
      volumes:
      - name: influxdb-storage
        emptyDir: {}
---
apiVersion: v1
kind: Service
metadata:
  labels:
    task: monitoring
    # For use as a Cluster add-on (https://github.com/kubernetes/kubernetes/tree/master/cluster/addons)
    # If you are NOT using this as an addon, you should comment out this line.
    kubernetes.io/cluster-service: 'true'
    kubernetes.io/name: monitoring-influxdb
  name: monitoring-influxdb
  namespace: kube-system
spec:
  ports:
  - port: 8086
    targetPort: 8086
  selector:
    k8s-app: influxdb

2）Service
默认不需要修改 Service 部分，注意 Service 名字的对应即可。

6.grafana.yaml

grafana.yaml 由 2 个模块组成：Deployment，Service。

1）Deployment
# 修改处：第 16 行，变更镜像名；
# 修改处：第 43 行，取消注释；“GF_SERVER_ROOT_URL”的 value 值设定后，只能通过API Server proxy 访问 grafana；
# 修改处：第 44 行，注释本行；
# INFLUXDB_HOST 的 value 值设定为 influxdb 的 service 名，依赖于集群 dns，或者直接使用 ClusterIP
[root@kubenode1 influxdb]# sed -i 's|gcr.io/google_containers/heapster-grafana-amd64:v4.4.3|netonline/heapster-grafana-amd64:v4.4.3|g' grafana.yaml 
[root@kubenode1 influxdb]# sed -i '43s|# value:|value:|g' grafana.yaml 
[root@kubenode1 influxdb]# sed -i '44s|value:|# value:|g' grafana.yaml 
[root@kubenode1 influxdb]# vi grafana.yaml

apiVersion: apps/v1
kind: Deployment
metadata:
  name: monitoring-grafana
  namespace: kube-system
spec:
  replicas: 1
  selector: 
    matchLabels:
      app: grafana
  template:
    metadata:
      labels:
        task: monitoring
        app: grafana
    spec:
      containers:
      - name: grafana
        image: netonline/heapster-grafana-amd64:v4.4.3
        ports:
        - containerPort: 3000
          protocol: TCP
        volumeMounts:
        - mountPath: /etc/ssl/certs
          name: ca-certificates
          readOnly: true
        - mountPath: /var
          name: grafana-storage
        env:
        - name: INFLUXDB_HOST
          value: monitoring-influxdb
        - name: GF_SERVER_HTTP_PORT
          value: "3000"
          # The following env variables are required to make Grafana accessible via
          # the kubernetes api-server proxy. On production clusters, we recommend
          # removing these env variables, setup auth for grafana, and expose the grafana
          # service using a LoadBalancer or a public IP.
        - name: GF_AUTH_BASIC_ENABLED
          value: "false"
        - name: GF_AUTH_ANONYMOUS_ENABLED
          value: "true"
        - name: GF_AUTH_ANONYMOUS_ORG_ROLE
          value: Admin
        - name: GF_SERVER_ROOT_URL
          # If you're only using the API Server proxy, set this value instead:
          # value: /api/v1/namespaces/kube-system/services/monitoring-grafana/proxy
          value: /
      volumes:
      - name: ca-certificates
        hostPath:
          path: /etc/ssl/certs
      - name: grafana-storage
        emptyDir: {}
---
apiVersion: v1
kind: Service
metadata:
  labels:
    # For use as a Cluster add-on (https://github.com/kubernetes/kubernetes/tree/master/cluster/addons)
    # If you are NOT using this as an addon, you should comment out this line.
    kubernetes.io/cluster-service: 'true'
    kubernetes.io/name: monitoring-grafana
  name: monitoring-grafana
  namespace: kube-system
spec:
  # In a production setup, we recommend accessing Grafana through an external Loadbalancer
  # or through a public IP.
  # type: LoadBalancer
  # You could also use NodePort to expose the service at a randomly-generated port
  type: NodePort
  ports:
  - port: 80
    targetPort: 3000
  selector:
    k8s-app: grafana

2）Service
默认不需要修改 Service 部分，注意 Service 名字的对应即可。

四、验证Kubernetes 集群性能监控

1.启动监控相关服务

# 将 heapster-rbac.yaml 复制到 influxdb/目录；
[root@kubenode1 ~]# cd /usr/local/heapster/deploy/kube-config/influxdb/ 
[root@kubenode1 influxdb]# cp /usr/local/heapster/deploy/kube-config/rbac/heapster-rbac.yaml .
[root@kubenode1 influxdb]# kubectl create -f .

2.查看相关服务

[root@kubernetes-master-001 /usr/local/heapster/deploy/kube-config/influxdb]# kubectl  get  deployments.apps  -n kube-system |grep -E 'heapster|monitoring'
heapster              1/1     1            1           7m57s
monitoring-grafana    1/1     1            1           12m
monitoring-influxdb   1/1     1            1           4m31s

[root@kubernetes-master-001 /usr/local/heapster/deploy/kube-config/influxdb]# kubectl  get  pods  -n kube-system |grep -E 'heapster|monitoring'
heapster-5b94686b4d-dn2gf                       1/1     Running   0          8m9s
monitoring-grafana-f65bfb89-d6fr5               1/1     Running   0          11m
monitoring-influxdb-7b75748dfd-2xf67            1/1     Running   0          60s

五、访问Dashboard

浏览器访问访问 dashboard：https://192.168.13.100:30028/#/pod?namespace=default (前提要装Dasheboard界面)
注意：Dasheboard 没有配置 hepster 监控平台时，不能展示 node，Pod 资源的 CPU 与内存等 metric 图形

Node 资源 CPU/内存 metric 图形：

Pod 资源 CPU/内存 metric 图形：

六、访问 grafana

1.查看grafana对外访问端口

[root@kubernetes-master-001 /usr/local/heapster/deploy/kube-config/influxdb]# kubectl  get svc -n kube-system 
NAME                  TYPE        CLUSTER-IP       EXTERNAL-IP   PORT(S)                  AGE
monitoring-grafana    NodePort    10.106.49.124            80:30353/TCP             118m

2.浏览器访问

浏览器访问：http://192.168.13.100:30353/?orgId=1

3.集群节点信息

4.Pod信息

七、K8S监控组件metrics-server

1.创建用户

Metrics-server需要读取kubernetes中数据，所以需要创建一个有权限的用户来给metrics-server使用。

[root@kubernetes-master-001 ~]# kubectl create clusterrolebinding system:anonymous --clusterrole=cluster-admin --user=system:anonymous
clusterrolebinding.rbac.authorization.k8s.io/system:anonymous created

2.创建配置文件

[root@kubernetes-master-001 ~]# vi components.yaml

apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRole
metadata:
  name: system:aggregated-metrics-reader
  labels:
    rbac.authorization.k8s.io/aggregate-to-view: "true"
    rbac.authorization.k8s.io/aggregate-to-edit: "true"
    rbac.authorization.k8s.io/aggregate-to-admin: "true"
rules:
- apiGroups: ["metrics.k8s.io"]
  resources: ["pods", "nodes"]
  verbs: ["get", "list", "watch"]
---
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRoleBinding
metadata:
  name: metrics-server:system:auth-delegator
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: ClusterRole
  name: system:auth-delegator
subjects:
- kind: ServiceAccount
  name: metrics-server
  namespace: kube-system
---
apiVersion: rbac.authorization.k8s.io/v1
kind: RoleBinding
metadata:
  name: metrics-server-auth-reader
  namespace: kube-system
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: Role
  name: extension-apiserver-authentication-reader
subjects:
- kind: ServiceAccount
  name: metrics-server
  namespace: kube-system
---
apiVersion: apiregistration.k8s.io/v1
kind: APIService
metadata:
  name: v1beta1.metrics.k8s.io
spec:
  service:
    name: metrics-server
    namespace: kube-system
  group: metrics.k8s.io
  version: v1beta1
  insecureSkipTLSVerify: true
  groupPriorityMinimum: 100
  versionPriority: 100
---
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: {}
      - name: ca-ssl
        hostPath:
         path: /etc/kubernetes/ssl
      containers:
      - name: metrics-server
        image: registry.cn-hangzhou.aliyuncs.com/k8sos/metrics-server:v0.4.1
        imagePullPolicy: IfNotPresent
        args:
          - --cert-dir=/tmp
          - --secure-port=4443
          - --metric-resolution=30s
          - --kubelet-insecure-tls
          - --kubelet-preferred-address-types=InternalIP,ExternalIP,Hostname
          - --requestheader-username-headers=X-Remote-User
          - --requestheader-group-headers=X-Remote-Group
          - --requestheader-extra-headers-prefix=X-Remote-Extra-
        ports:
        - name: main-port
          containerPort: 4443
          protocol: TCP
        securityContext:
          readOnlyRootFilesystem: true
          runAsNonRoot: true
          runAsUser: 1000
        volumeMounts:
        - name: tmp-dir
          mountPath: /tmp
        - name: ca-ssl
          mountPath: /etc/kubernetes/ssl
      nodeSelector:
        kubernetes.io/os: linux
---
apiVersion: v1
kind: Service
metadata:
  name: metrics-server
  namespace: kube-system
  labels:
    kubernetes.io/name: "Metrics-server"
    kubernetes.io/cluster-service: "true"
spec:
  selector:
    k8s-app: metrics-server
  ports:
  - port: 443
    protocol: TCP
    targetPort: main-port
---
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRole
metadata:
  name: system:metrics-server
rules:
- apiGroups:
  - ""
  resources:
  - pods
  - nodes
  - nodes/stats
  - namespaces
  - configmaps
  verbs:
  - get
  - list
  - watch
---
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRoleBinding
metadata:
  name: system:metrics-server
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: ClusterRole
  name: system:metrics-server
subjects:
- kind: ServiceAccount
  name: metrics-server
  namespace: kube-system

3.创建服务

[root@kubernetes-master-001 ~]# kubectl apply -f components.yaml
clusterrole.rbac.authorization.k8s.io/system:aggregated-metrics-reader created
clusterrolebinding.rbac.authorization.k8s.io/metrics-server:system:auth-delegator created
rolebinding.rbac.authorization.k8s.io/metrics-server-auth-reader created
apiservice.apiregistration.k8s.io/v1beta1.metrics.k8s.io created
serviceaccount/metrics-server created
deployment.apps/metrics-server created
service/metrics-server created
clusterrole.rbac.authorization.k8s.io/system:metrics-server created
clusterrolebinding.rbac.authorization.k8s.io/system:metrics-server created