详细错误：
1 com.sun.jersey.api.client.ClientHandlerException: org.apache.http.conn.ConnectTimeoutException: Connect to localhost:8761 timed out 2 at com.sun.jersey.client.apache4.ApacheHttpClient4Handler.handle(ApacheHttpClient4Handler.java:187) ~[jersey-apache-client4-1.19.1.jar:1.19.1] 3 at com.netflix.eureka.cluster.DynamicGZIPContentEncodingFilter.handle(DynamicGZIPContentEncodingFilter.java:48) ~[eureka-core-1.7.2.jar:1.7.2] 4 at com.netflix.discovery.EurekaIdentityHeaderFilter.handle(EurekaIdentityHeaderFilter.java:27) ~[eureka-client-1.7.2.jar:1.7.2] 5 at com.sun.jersey.api.client.Client.handle(Client.java:652) ~[jersey-client-1.19.1.jar:1.19.1] 6 at com.sun.jersey.api.client.WebResource.handle(WebResource.java:682) ~[jersey-client-1.19.1.jar:1.19.1] 7 at com.sun.jersey.api.client.WebResource.access$200(WebResource.java:74) ~[jersey-client-1.19.1.jar:1.19.1] 8 at com.sun.jersey.api.client.WebResource$Builder.post(WebResource.java:570) ~[jersey-client-1.19.1.jar:1.19.1] 9 at com.netflix.eureka.transport.JerseyReplicationClient.submitBatchUpdates(JerseyReplicationClient.java:116) ~[eureka-core-1.7.2.jar:1.7.2] 10 at com.netflix.eureka.cluster.ReplicationTaskProcessor.process(ReplicationTaskProcessor.java:71) ~[eureka-core-1.7.2.jar:1.7.2] 11 at com.netflix.eureka.util.batcher.TaskExecutors$BatchWorkerRunnable.run(TaskExecutors.java:187) [eureka-core-1.7.2.jar:1.7.2] 12 at java.lang.Thread.run(Thread.java:748) [na:1.8.0_202] 13 Caused by: org.apache.http.conn.ConnectTimeoutException: Connect to localhost:8761 timed out 14 at org.apache.http.conn.scheme.PlainSocketFactory.connectSocket(PlainSocketFactory.java:123) ~[httpclient-4.5.8.jar:4.5.8] 15 at org.apache.http.impl.conn.DefaultClientConnectionOperator.openConnection(DefaultClientConnectionOperator.java:180) ~[httpclient-4.5.8.jar:4.5.8] 16 at org.apache.http.impl.conn.AbstractPoolEntry.open(AbstractPoolEntry.java:144) ~[httpclient-4.5.8.jar:4.5.8] 17 at org.apache.http.impl.conn.AbstractPooledConnAdapter.open(AbstractPooledConnAdapter.java:134) ~[httpclient-4.5.8.jar:4.5.8] 18 at org.apache.http.impl.client.DefaultRequestDirector.tryConnect(DefaultRequestDirector.java:605) ~[httpclient-4.5.8.jar:4.5.8] 19 at org.apache.http.impl.client.DefaultRequestDirector.execute(DefaultRequestDirector.java:440) ~[httpclient-4.5.8.jar:4.5.8] 20 at org.apache.http.impl.client.AbstractHttpClient.doExecute(AbstractHttpClient.java:835) ~[httpclient-4.5.8.jar:4.5.8] 21 at org.apache.http.impl.client.CloseableHttpClient.execute(CloseableHttpClient.java:118) ~[httpclient-4.5.8.jar:4.5.8] 22 at org.apache.http.impl.client.CloseableHttpClient.execute(CloseableHttpClient.java:56) ~[httpclient-4.5.8.jar:4.5.8] 23 at com.sun.jersey.client.apache4.ApacheHttpClient4Handler.handle(ApacheHttpClient4Handler.java:173) ~[jersey-apache-client4-1.19.1.jar:1.19.1] 24 ... 10 common frames omitted
疑问：我哪里根本没有使用到端口为：8761 的应用，经过一番百度查阅，终于让我找到答案了。原来问题出在 EurekaClientConfigBean 这个类，源码如下：
1 package org.springframework.cloud.netflix.eureka; 2 import ... 3 @ConfigurationProperties("eureka.client") 4 public class EurekaClientConfigBean implements EurekaClientConfig { 5 public static final String PREFIX = "eureka.client"; 6 public static final String DEFAULT_URL = "http://localhost:8761/eureka/"; // 问题的所在，原来 springcloud 源码这里定义了 7 public static final String DEFAULT_ZONE = "defaultZone"; 8 private static final int MINUTES = 60; 9 @Autowired( 10 required = false 11 ) 12 ..... 13 public EurekaClientConfigBean() { 14 this.serviceUrl.put("defaultZone", "http://localhost:8761/eureka/"); 15 this.gZipContent = true; 16 this.useDnsForFetchingServiceUrls = false; 17 this.registerWithEureka = true; 18 this.preferSameZoneEureka = true; 19 this.availabilityZones = new HashMap(); 20 this.filterOnlyUpInstances = true; 21 this.fetchRegistry = true; 22 this.dollarReplacement = "_-"; 23 this.escapeCharReplacement = "__"; 24 this.allowRedirects = false; 25 this.onDemandUpdateStatusChange = true; 26 this.clientDataAccept = EurekaAccept.full.name(); 27 this.shouldUnregisterOnShutdown = true; 28 this.shouldEnforceRegistrationAtInit = false; 29 } 30 ... 31 }
解决方案：使用你的端口号去覆盖里面的端口，即：
eureka.client.service-url.defaultZone=http://eureka1:5121/eureka/ // 写你的ip及端口