EurekaServer集群配置

一、程序配置

1、pom添加依赖：

<dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-eureka-server</artifactId>
</dependency>

　　(这里因为在pom中通过dependencyManagement配置将spring-cloud-dependencies import进来，所以不需要写版本号)

　　或者在是使用Spring Initializr创建SpringBoot项目时，添加上起步依赖Eureka Server (路径：Cloud Discovery -- Eureka Server)。

　　完整pom为：

<?xml version="1.0" encoding="UTF-8"?>
<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">
    <modelVersion>4.0.0</modelVersion>

    <groupId>com.example</groupId>
    <artifactId>microservice-discovery-eureka-ha</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>jar</packaging>

    <name>microservice-discovery-eureka-ha</name>
    <description>Demo project for Spring Boot</description>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.1.1.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>

    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
        <java.version>1.8</java.version>
        <spring-cloud.version>Greenwich.M3</spring-cloud.version>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-eureka-server</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
    </dependencies>

    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-dependencies</artifactId>
                <version>${spring-cloud.version}</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
        </dependencies>
    </dependencyManagement>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>

    <repositories>
        <repository>
            <id>spring-milestones</id>
            <name>Spring Milestones</name>
            <url>https://repo.spring.io/milestone</url>
            <snapshots>
                <enabled>false</enabled>
            </snapshots>
        </repository>
    </repositories>

</project>

2、在SpringBoot启动类上添加注释@EnableEurekaServer

3、配置application.yml或application.properties

spring:
  application:
    name: microservice-discovery-eureka-ha

---
spring:
  profiles: peer1
server:
  port: 8761
eureka:
  instance:
    hostname: peer1
  client:
    service-url:
      defaultZone: http://peer2:8762/eureka/
    register-with-eureka: false #作为对比，这里表示不将peer1注册到Eureka Server集群中，peer2中默认为true
    fetch-registry: false  #作为对比，这里表示peer1不会从Eureka Server集群获取注册表信息
---
spring:
  profiles: peer2
server:
  port: 8762
eureka:
  instance:
    hostname: peer2
  client:
    service-url:
      defaultZone: http://peer1:8761/eureka/

　　例子程序的github地址是：https://github.com/zjianliu/Eureka-Server

二、程序运行

　　将程序打包后，执行jar包：

java -jar xxx.jar --spring.profiles.active=peer1
java -ajr xxx.jar --spring.profiles.active=peer2

　　通过spring.profiles.active指定使用application.yml中配置的哪一个profile启动程序。

三、程序截图

　　我们可以看到，peer2将自身注册到Eureka Server集群中了，而peer1没有。

　　Eureka Server配置启动好之后，我们就可以写微服务，并通过配置将其注册到Eureka Server集群中了