【云原生 | Kubernetes 系列】---Prometheus 监控Java服务

1. Prometheus 监控Java服务

基于第三方exporter实现对目的服务的监控
监控tomcat的活跃连接数,堆栈内存等信息:

tomcat_connections_active_total{name="http-nio-8080",} 2.0
jvm_memory_bytes_used{area="heap",} 2.4451216E7

2. 自定义镜像

FROM tomcat:8.5.73

ADD server.xml /usr/local/tomcat/conf/server.xml 

RUN mkdir /data/tomcat/webapps -p
ADD myapp /data/tomcat/webapps/myapp
ADD metrics.war /data/tomcat/webapps 
ADD simpleclient-0.8.0.jar  /usr/local/tomcat/lib/
ADD simpleclient_common-0.8.0.jar /usr/local/tomcat/lib/
ADD simpleclient_hotspot-0.8.0.jar /usr/local/tomcat/lib/
ADD simpleclient_servlet-0.8.0.jar /usr/local/tomcat/lib/
ADD tomcat_exporter_client-0.0.12.jar /usr/local/tomcat/lib/

EXPOSE 8080 8443 8009

构建镜像

#!/bin/bash
docker build -t harbor.intra.com/wework/tomcat-app1:v1 .

docker push harbor.intra.com/wework/tomcat-app1:v1

启动镜像看一下是否正常

docker run --rm -it -p 8801:8080 harbor.intra.com/wework/tomcat-app1:v1

3. 用Pod方式运行

apiVersion: apps/v1
kind: Deployment
metadata:
  name: tomcat-deployment
  namespace: default
spec:
  selector: 
    matchLabels: 
     app: tomcat
  replicas: 1 # tells deployment to run 2 pods matching the template
  template: # create pods using pod definition in this template
    metadata:
      labels:
        app: tomcat
      annotations:
        prometheus.io/scrape: 'true'
    spec:
      containers:
      - name: tomcat
        image: harbor.intra.com/wework/tomcat-app1:v1
        ports:
        - containerPort: 8080
        securityContext: 
          privileged: true
---
kind: Service
apiVersion: v1
metadata:
  name: tomcat-service
spec:
  selector:
    app: tomcat
  ports:
  - nodePort: 31080
    port: 80
    protocol: TCP
    targetPort: 8080
  type: NodePort

部署

kubectl apply -f tomcat-deploy.yaml 

先测试是否可以打开nodeport的metrics页面

prometheus添加对nodeport的监控

  - job_name: "k8s-tomcat-31080"
    metrics_path: /metrics
    static_configs:
      - targets: ["192.168.31.113:31080"]

重启prometheus后就能在prometheus中看到tomcat的信息

grafana导入