在k8s中副本使用pod的IP注冊到consul全過程

更新時間：2026年02月25日 09:51:35 作者：October-

文章介紹了如何在Kubernetes環(huán)境中通過DNS獲取POD的IP,并將其用于注冊到Consul,通過修改服務啟動腳本和Kubernetes樣本文件,使得微服務能夠獲取POD信息并使用該IP注冊到Consul,從而實現(xiàn)服務間的發(fā)現(xiàn)和通信

1、通過DNS獲取POD的IP

1.1、服務啟動腳本

#!/bin/bash
# 啟動服務，獲得pod中的IP，POD中的hosts配置最后一行就是它自己的IP
export HOST_IP=$(tail -n 1 /etc/hosts|awk 'END {print}'| awk '{for(i =1; i <=NF; i++){ if($i~/[0-9]\.[0-9]/) print $i}}')
echo ${HOST_IP}
#通過環(huán)境變量傳遞給微服務
java -jar -DHOST_IP=${HOST_IP} /opt/service/sample/sample-0.0.1-SNAPSHOT.jar --spring.profiles.active=prod

1.2、微服務修改配置

spring:
  application:
    name: sample
  cloud:
    consul:
      host: ${consul_host:10.0.10.110}
      port: ${consul_port:8500}
      discovery:
        register: true
        service-name: ${spring.application.name}
        health-check-path: /actuator/health
        healthCheckInterval: 10s
        tags: urlprefix-/${spring.application.name}
        instance-id: {spring.application.instance_id:${random.value}}}
        health-check-critical-timeout: 30s
        hostname: ${HOST_IP}

2、在K8S的樣本文件通過env獲取 POD信息

參考：https://kubernetes.io/docs/tasks/inject-data-application/environment-variable-expose-pod-information/

2.1、樣本文件修改

…………
        env:
        - name: CONSUL_HOST
          value: 10.0.10.110
        - name: NODE_NAME
          valueFrom:
            fieldRef:
              fieldPath: spec.nodeName
        - name: POD_IP
          valueFrom:
            fieldRef:
              fieldPath: status.podIP
………….

2.2、檢查環(huán)境變量是否生效

[root@kvm13-pre ~]# kubectl exec -it sample-6f7fcd5567-9sxl9 -n lenovo /bin/bash
root@sample-6f7fcd5567-9sxl9:/opt/service/sample# echo $POD_IP
10.244.3.94
root@sample-6f7fcd5567-9sxl9:/opt/service/sample#

2.3、服務啟動腳本

#!/bin/bash
# 啟動服務
java -jar -DHOST_IP=${POD_IP}  /opt/service/lenovo_sample/sample-service-0.0.1-SNAPSHOT.jar --spring.profiles.active=prod

2.4、微服務修改配置

spring:
  application:
    name: sample
  cloud:
    consul:
      host: ${consul_host:10.0.10.110}
      port: ${consul_port:8500}
      discovery:
        register: true
        service-name: ${spring.application.name}
        health-check-path: /actuator/health
        healthCheckInterval: 10s
        tags: urlprefix-/${spring.application.name}
        instance-id: {spring.application.instance_id:${random.value}}}
        health-check-critical-timeout: 30s
        hostname: ${HOST_IP}