1.什么是Eureka？

Eureka 由 Netflix 开发，是一种基于REST（Representational State Transfer）的服务，用于定位服务（服务注册与发现），以实现中间层服务的负载均衡和故障转移，此服务被称为 Eureka Server。同时，它还附带了基于 Java 的客户端组件：Eureka Client，它使得客户端与 Eureka Server 的交互变得更加的容易。以下就是一个简单的服务调用过程：

由服务提供方将服务注册到 Eureka Server
服务消费者通过 Eureka Server 获取服务提供方的真实地址
服务消费者通过真实的地址调用服务

2.代码工程

实验目的

搭建Eureka集群

pom.xml

<project xmlns="http://maven.apache.org/POM/4.0.0"         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">    <parent>        <artifactId>eurekaartifactId>        <groupId>com.etgroupId>        <version>1.0-SNAPSHOTversion>    parent>    <modelVersion>4.0.0modelVersion>
    <artifactId>eureka-serverartifactId>
    <properties>        <maven.compiler.source>8maven.compiler.source>        <maven.compiler.target>8maven.compiler.target>    properties>    <dependencies>        <dependency>            <groupId>org.springframework.bootgroupId>            <artifactId>spring-boot-starter-webartifactId>        dependency>        <dependency>            <groupId>org.springframework.bootgroupId>            <artifactId>spring-boot-starter-actuatorartifactId>        dependency>        <dependency>            <groupId>org.springframework.bootgroupId>            <artifactId>spring-boot-starter-testartifactId>            <scope>testscope>        dependency>        <dependency>            <groupId>org.projectlombokgroupId>            <artifactId>lombokartifactId>            <optional>trueoptional>        dependency>        <dependency>            <groupId>org.springframework.cloudgroupId>            <artifactId>spring-cloud-starter-netflix-eureka-serverartifactId>            <version>${eureka.version}version>        dependency>    dependencies>
project>

EurekaServerApplication

package com.et.eureka;
import org.springframework.boot.SpringApplication;import org.springframework.boot.autoconfigure.SpringBootApplication;import org.springframework.cloud.netflix.eureka.server.EnableEurekaServer;
@EnableEurekaServer@SpringBootApplicationpublic class EurekaServerApplication {
  public static void main(String[] args) {    SpringApplication.run(EurekaServerApplication.class, args);  }}

节点1配置信息

server:  port: 8761
eureka:  instance:    hostname: node1 # eureka name    prefer-ip-address: false  client:    fetch-registry: false    register-with-eureka: true    # eureka url    service-url:      defaultZone: http://node2:8762/eurekaspring:  application:    name: "eureka-server-ha"

节点2配置信息

server:  port: 8762
eureka:  instance:    hostname: node2 # eureka name    prefer-ip-address: false  client:    fetch-registry: false    register-with-eureka: true    # eureka url    service-url:      defaultZone: http://node1:8761/eurekaspring:  application:    name: "eureka-server-ha"

配置本机host

/etc/hosts

127.0.0.1 node1127.0.0.1 node2

以上只是一些关键代码，所有代码请参见下面代码仓库

代码仓库

https://github.com/Harries/springcloud-demo

3.测试

启动node1，node2

访问http://127.0.0.1:8761/

4.引用

https://docs.spring.io/spring-cloud-netflix/docs/current/reference/html/#service-discovery-eureka-clients
https://nicklee1006.github.io/Spring-Cloud-3-Eureka-Clustering/
http://www.liuhaihua.cn/archives/710895.html

Spring Cloud Eureka快读入门Demo