通过docker和docker-compose实现eureka高可用

   最近新项目有使用到springcloud 和docker，关于这两个技术就不分别介绍了，现在分享一下通过docker,docker-compose实现eureka高可用的方案。

   1. eureka server项目目录结构：

  

   2. eureka 配置文件配置：

    

server:
  port: 8900

spring:
  application:
    name: eureka-server
  profiles:
    active: dev

management:
  security:
    enabled: false
  health:
    rabbit:
      enabled: false

---
spring:
  profiles: dev

eureka:
  client:
    serviceUrl:
      defaultZone: http://localhost:${server.port}/eureka/
    register-with-eureka: false
    fetch-registry: false
  instance:
    hostname: localhost
    prefer-ip-address: true

---
spring:
  profiles: test_ha_1

eureka:
  client:
    serviceUrl:
      defaultZone: http://eurekaserver2:${server.port}/eureka/
  instance:
    hostname: eurekaserver1
#    prefer-ip-address: true  该配置为true表示注册到eureka上的是IP，如果这样的化，eureka服务器就不能通过服务器发现Replicas。
#                             故如果想通过Docker实现eureka高可用，该配置最好使用默认值（false）
#                             此处配置为true且实现高可用也不是没有办法，就是每个eureka服务需映射到Docker环境外，且知道ip。
---
spring:
  profiles: test_ha_2

eureka:
  client:
    serviceUrl:
      defaultZone: http://eurekaserver1:${server.port}/eureka/
  instance:
    hostname: eurekaserver2
#    prefer-ip-address: true

    3. docker maven插件配置：

    

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
            <plugin>
                <groupId>com.spotify</groupId>
                <artifactId>docker-maven-plugin</artifactId>
                <version>0.4.13</version>
                <configuration>
                    <imageName>${docker.image.prefix}/${project.artifactId}:${project.version}</imageName>
                    <dockerDirectory>src/main/docker</dockerDirectory>
                    <forceTags>true</forceTags>
                    <resources>
                        <resource>
                            <targetPath>/</targetPath>
                            <directory>${project.build.directory}</directory>
                        </resource>
                    </resources>
                </configuration>
                <!--<groupId>com.spotify</groupId>
                <artifactId>docker-maven-plugin</artifactId>
                <version>0.4.13</version>
                <configuration>
                    <imageName>itmuch/${project.artifactId}:${project.version}</imageName>
                    <forceTags>true</forceTags>
                    <baseImage>java</baseImage>
                    <entryPoint>["java", "-jar", "/${project.build.finalName}.jar"]</entryPoint>
                    <resources>
                        <resource>
                            <targetPath>/</targetPath>
                            <directory>${project.build.directory}</directory>
                            <include>${project.build.finalName}.jar</include>
                        </resource>
                    </resources>
                </configuration>-->
            </plugin>
        </plugins>
    </build>

    4. Docker file 文件内容：

   

FROM java:8

ADD eureka-server-1.0.0.jar eurekaserver.jar
ENTRYPOINT ["java","-Djava.security.egd=file:/dev/./urandom","-jar","/eurekaserver.jar"]

    5. 生成 eureka server 镜像：

    通过执行 mvn clean package docker:build 命令，生成eurekaserver镜像，如下：

     

      6.  通过docker-compose 编排：

      

version: '2'
services:
  eurekaserver1:
    image: raynspace/eureka-server:1.0.0
    ports:
      - "7900:8900"
    environment:
      - spring.profiles.active=test_ha_1

  eurekaserver2:
    image: raynspace/eureka-server:1.0.0
    #hostname: eurekaserver2
    ports:
      - "7800:8900"
    environment:
      - spring.profiles.active=test_ha_2

     7. 跳转至项目目录下，执行docker-compose up 命令，自动生成eureka server 两个容器：

   

     8. 由于已经把eureka 端口映射出来，所以本地通过端口访问eureka，查看eureka 服务状态：

  

  通过上图可知，在registered-replicas和available-replicas两项均能看见另外一个eureka服务，至此eureka 集群搭建完成。