Spring Cloud Eureka 报错 java.net.UnknownHostException

落日映苍穹つ 2022-03-10 15:16 805阅读 0赞

在学习spring cloud 微服务时发现消费者无法注册到注册中心

已注册两个服务：

![2019031114341368.png][]

下面发一下服务消费者的代码：

### application 主入口： ###

@EnableDiscoveryClient   //开启发现服务功能
    @SpringBootApplication
    public class ConsumerUserApplication {
    
        public static void main(String[] args) {
            SpringApplication.run(ConsumerUserApplication.class, args);
        }
    
        @LoadBalanced  //使用负载均衡机制
        @Bean
        public RestTemplate restTemplate(){
            return new RestTemplate();
        }
    }

### Controller： ###

@RestController
    public class UserController {
    
        @Autowired
        RestTemplate restTemplate;
    
        @GetMapping("/buy")
        public String buyTicket(String name){
            String s = restTemplate.getForObject("http://PROVIDER-TICKET/ticket", String.class);
            return name+"购买了："+s;
        }
    }

### application.yml： ###

spring:
      application:
        name: consumer-user
    server:
      port: 8200
    
    
    eureka:
      instance:
        prefer-ip-address: true #注册服务的时候使用服务的IP地址
      client:
        service-url:
          defaultZone: http://localhost:8761/eureka/

启动主程序以后发现服务并没有注册到注册中心中

后来好奇访问了一下页面，结果页面报了500：

Whitelabel Error Page
    This application has no explicit mapping for /error, so you are seeing this as a fallback.
    
    Mon Mar 11 14:39:27 CST 2019
    There was an unexpected error (type=Internal Server Error, status=500).
    I/O error on GET request for "http://PROVIDER-TICKET/ticket": PROVIDER-TICKET; nested exception is java.net.UnknownHostException: PROVIDER-TICKET

参考了一下百度上的问题，大概意思是导入的包不对的缘故

导入下列包：

<dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-starter-netflix-ribbon</artifactId>
            </dependency>
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
            </dependency>
    
    
        </dependencies>
    
        <dependencyManagement>
            <dependencies>
                <dependency>
                    <groupId>org.springframework.cloud</groupId>
                    <artifactId>spring-cloud-dependencies</artifactId>
                    <version>Greenwich.SR1</version>
                    <type>pom</type>
                    <scope>import</scope>
                </dependency>
            </dependencies>
        </dependencyManagement>

![201903111450277.png][]

问题解决，成功注册到注册中心

[2019031114341368.png]: /images/20220310/6e7c40a2662944489c112ca3daf71d89.png
[201903111450277.png]: /images/20220310/398403372cae4affbacbe3b4fa2f88a0.png