2.Client Library: 客户端库，检测应用程序代码，当Prometheus抓取实例的HTTP端点时，客户端库会将所有跟踪的metrics指标的当前状态发送到prometheus server端。
3.Exporters: prometheus支持多种exporter，通过exporter可以采集metrics数据，然后发送到prometheus server端
4.Alertmanager: 从 Prometheus server 端接收到 alerts 后，会进行去重，分组，并路由到相应的接收方，发出报警，常见的接收方式有：电子邮件，微信，钉钉, slack等。
5.Grafana：监控仪表盘
6.pushgateway: 各个目标主机可上报数据到pushgatewy，然后prometheus server统一从pushgateway拉取数据。
prometheus架构图从上图可发现，Prometheus整个生态圈组成主要包括prometheus server，Exporter，pushgateway，alertmanager，grafana，Web ui界面，Prometheus server由三个部分组成，Retrieval，Storage，PromQL 。
retrieval负责在活跃的target主机上抓取监控指标数据
storage主要是把采集到的数据存储到磁盘中
promQL是prometheus提供的查询语言模块
prometheus工作流程Prometheus server可定期从活跃的（up）目标主机上（target）拉取监控指标数据，目标主机的监控数据可通过配置静态job或者服务发现的方式被prometheus server采集到，这种方式默认的pull方式拉取指标；也可通过pushgateway把采集的数据上报到prometheus server中；还可通过一些组件自带的exporter采集相应组件的数据；
Prometheus server把采集到的监控指标数据保存到本地磁盘或者数据库；
Prometheus采集的监控指标数据按时间序列存储，通过配置报警规则，把触发的报警发送到alertmanager
Alertmanager通过配置报警接收方，发送报警到邮件，微信或者钉钉等
Prometheus 自带的web ui界面提供PromQL查询语言，可查询监控数据
Grafana可接入prometheus数据源，把监控数据以图形化形式展示出
安装node-exporter组件 node-exporter是采集机器（物理机、虚拟机、云主机等）的监控指标数据，能够采集到的指标包括CPU, 内存，磁盘，网络，文件数等信息。
实验环境 一个master节点，一个node节点。
在master节点操作 cat >node-export.yaml <<EOF apiVersion: apps/v1 kind: DaemonSet metadata: name: node-exporter namespace: monitor-sa labels: name: node-exporter spec: selector: matchLabels: name: node-exporter template: metadata: labels: name: node-exporter spec: hostPID: true hostIPC: true hostNetwork: true containers: - name: node-exporter image: prom/node-exporter:v0.16.0 ports: - containerPort: 9100 resources: requests: cpu: 0.15 securityContext: privileged: true args: - --path.procfs - /host/proc - --path.sysfs - /host/sys - --collector.filesystem.ignored-mount-points - '"^/(sys|proc|dev|host|etc)($|/)"' volumeMounts: - name: dev mountPath: /host/dev - name: proc mountPath: /host/proc - name: sys mountPath: /host/sys - name: rootfs mountPath: /rootfs tolerations: - key: "node-role.kubernetes.io/master" operator: "Exists" effect: "NoSchedule" volumes: - name: proc hostPath: path: /proc - name: dev hostPath: path: /dev - name: sys hostPath: path: /sys - name: rootfs hostPath: path: / EOF 通过node-exporter采集数据 curl 主机ip:9100/metrics 在k8s集群中部署promethues
创建namespace、sa账号，在k8s集群的master节点操作
kubectl create ns monitor-sa kubectl create serviceaccount monitor -n monitor-sa #把sa账号monitor通过clusterrolebing绑定到clusterrole上 kubectl create clusterrolebinding moniror-clusterrolebinding -n monitor-sa --clusterrole=cluster-admin --serviceaccount=monitor-sa:monitor
创建数据目录
# 在k8s集群的任何一个node节点操作，本实验在node1上操作 mkdir /data chmod 777 /data/
安装prometheus，在master节点操作
#创建一个configmap存储卷，用来存放prometheus配置信息 #prometheus-cfg.yaml kind: ConfigMap apiVersion: v1 metadata: labels: app: prometheus name: prometheus-config namespace: monitor-sa data: prometheus.yml: | global: scrape_interval: 15s scrape_timeout: 10s evaluation_interval: 1m scrape_configs: - job_name: 'kubernetes-node' kubernetes_sd_configs: - role: node relabel_configs: - source_labels: [__address__] regex: '(.*):10250' replacement: ':9100' target_label: __address__ action: replace - action: labelmap regex: __meta_kubernetes_node_label_(.+) - job_name: 'kubernetes-node-cadvisor' kubernetes_sd_configs: - role: node scheme: https tls_config: ca_file: /var/run/secrets/kubernetes.io/serviceaccount/ca.crt bearer_token_file: /var/run/secrets/kubernetes.io/serviceaccount/token relabel_configs: - action: labelmap regex: __meta_kubernetes_node_label_(.+) - target_label: __address__ replacement: kubernetes.default.svc:443 - source_labels: [__meta_kubernetes_node_name] regex: (.+) target_label: __metrics_path__ replacement: /api/v1/nodes//proxy/metrics/cadvisor - job_name: 'kubernetes-apiserver' kubernetes_sd_configs: - role: endpoints scheme: https tls_config: ca_file: /var/run/secrets/kubernetes.io/serviceaccount/ca.crt bearer_token_file: /var/run/secrets/kubernetes.io/serviceaccount/token relabel_configs: - source_labels: [__meta_kubernetes_namespace, __meta_kubernetes_service_name, __meta_kubernetes_endpoint_port_name] action: keep regex: default;kubernetes;https - job_name: 'kubernetes-service-endpoints' kubernetes_sd_configs: - role: endpoints relabel_configs: - source_labels: [__meta_kubernetes_service_annotation_prometheus_io_scrape] action: keep regex: true - source_labels: [__meta_kubernetes_service_annotation_prometheus_io_scheme] action: replace target_label: __scheme__ regex: (https?) - source_labels: [__meta_kubernetes_service_annotation_prometheus_io_path] action: replace target_label: __metrics_path__ regex: (.+) - source_labels: [__address__, __meta_kubernetes_service_annotation_prometheus_io_port] action: replace target_label: __address__ regex: ([^:]+)(?::\d+)?;(\d+) replacement: : - action: labelmap regex: __meta_kubernetes_service_label_(.+) - source_labels: [__meta_kubernetes_namespace] action: replace target_label: kubernetes_namespace - source_labels: [__meta_kubernetes_service_name] action: replace target_label: kubernetes_name --- #通过deployment部署prometheus #prometheus-deploy.yaml apiVersion: apps/v1 kind: Deployment metadata: name: prometheus-server namespace: monitor-sa labels: app: prometheus spec: replicas: 1 selector: matchLabels: app: prometheus component: server template: metadata: labels: app: prometheus component: server annotations: prometheus.io/scrape: 'false' spec: nodeName: node1 serviceAccountName: monitor containers: - name: prometheus image: prom/prometheus:v2.2.1 imagePullPolicy: IfNotPresent command: - prometheus - --config.file=http://www.likecs.com/etc/prometheus/prometheus.yml - --storage.tsdb.path=http://www.likecs.com/prometheus - --storage.tsdb.retention=720h ports: - containerPort: 9090 protocol: TCP volumeMounts: - mountPath: /etc/prometheus/prometheus.yml name: prometheus-config subPath: prometheus.yml - mountPath: /prometheus/ name: prometheus-storage-volume volumes: - name: prometheus-config configMap: name: prometheus-config items: - key: prometheus.yml path: prometheus.yml mode: 0644 - name: prometheus-storage-volume hostPath: path: /data type: Directory