Spring Cloud：Cannot execute request on any known server - 版本不一致问题

简介

Error : Cannot execute request on any known server

翻译过来就是：无法在任何已知服务器上执行请求。这个错误提示信息，相信小伙伴们在配置SpringCloud的时候，经常会遇到。虽然这个错误提示看似简单，但是能够引发它的原因就太多了，多不胜数，任何一点配置发生错误，都可能导致发生这个错误。

---

以下解决该错误的一种原因，是由于版本不一致导致的错误。

还原错误发生情况

导致错误：虽然Provider可以正常对Consumer提供服务，可以正常注册Eureka，但是会一直报错误。

错误大致信息

c.n.d.s.t.d.RedirectingEurekaHttpClient  : `Request execution error`
`javax.ws.rs.WebApplicationException: null`com.netflix.discovery.DiscoveryClient    : DiscoveryClient_PROVIDER-DEMO/192.168.1.101:provider-demo:8000 - `was unable to refresh its cache! status = Cannot execute request on any known server`
com.netflix.discovery.shared.transport.TransportException: `Cannot execute request on any known server`

父项目pom文件配置信息

<!-- 父项目引入的Spring Boot版本号 -->
<parent><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-parent</artifactId><version>2.1.3.RELEASE</version><relativePath/> <!-- lookup parent from repository -->
</parent>
<!-- 父项目引入的Spring Cloud版本号，Finchley.RELEASE对应的是Spring Boot 2.X版本 -->
<properties><spring.cloud.version>Finchley.RELEASE</spring.cloud.version>
</properties>
<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>

子项目pom文件配置信息

错误分析，当写了<version>RELEASE</version>，导入的是与Spring Boot相对应地版本号，默认导入的是<version>Finchley.RELEASE</version>中管理的版本号

<!-- 默认引入eureka-clent，版本号为：2.0.0.RELEASE -->
<dependency><groupId>org.springframework.cloud</groupId><artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
</dependency>
<!-- 当我们写了`<version>RELEASE</version>`后，引入eureka-client，版本号为：2.1.3.RELEASE -->
<dependency><groupId>org.springframework.cloud</groupId><artifactId>spring-cloud-starter-netflix-eureka-client</artifactId><version>RELEASE</version>
</dependency>

默认导入与RELEASE对比

Finchley.RELEASE中管理的版本号

完整错误信息

2019-10-24 09:23:54.766  INFO 59687 --- [freshExecutor-0] com.netflix.discovery.DiscoveryClient    : Disable delta property : false
2019-10-24 09:23:54.766  INFO 59687 --- [freshExecutor-0] com.netflix.discovery.DiscoveryClient    : Single vip registry refresh property : null
2019-10-24 09:23:54.767  INFO 59687 --- [freshExecutor-0] com.netflix.discovery.DiscoveryClient    : Force full registry fetch : false
2019-10-24 09:23:54.767  INFO 59687 --- [freshExecutor-0] com.netflix.discovery.DiscoveryClient    : Application is null : false
2019-10-24 09:23:54.767  INFO 59687 --- [freshExecutor-0] com.netflix.discovery.DiscoveryClient    : Registered Applications size is zero : true
2019-10-24 09:23:54.767  INFO 59687 --- [freshExecutor-0] com.netflix.discovery.DiscoveryClient    : Application version is -1: true
2019-10-24 09:23:54.767  INFO 59687 --- [freshExecutor-0] com.netflix.discovery.DiscoveryClient    : Getting all instance registry info from the eureka server
2019-10-24 09:23:54.772 ERROR 59687 --- [freshExecutor-0] c.n.d.provider.DiscoveryJerseyProvider   : Unexpected error occurred during de-serialization of discovery data, done connection cleanup
2019-10-24 09:23:54.772 ERROR 59687 --- [freshExecutor-0] c.n.d.s.t.d.RedirectingEurekaHttpClient  : Request execution errorjavax.ws.rs.WebApplicationException: nullat com.netflix.discovery.provider.DiscoveryJerseyProvider.readFrom(DiscoveryJerseyProvider.java:107) ~[eureka-client-1.9.2.jar:1.9.2]at com.sun.jersey.api.client.ClientResponse.getEntity(ClientResponse.java:634) ~[jersey-client-1.19.1.jar:1.19.1]at com.sun.jersey.api.client.ClientResponse.getEntity(ClientResponse.java:586) ~[jersey-client-1.19.1.jar:1.19.1]at com.netflix.discovery.shared.transport.jersey.AbstractJerseyEurekaHttpClient.getApplicationsInternal(AbstractJerseyEurekaHttpClient.java:198) ~[eureka-client-1.9.2.jar:1.9.2]at com.netflix.discovery.shared.transport.jersey.AbstractJerseyEurekaHttpClient.getApplications(AbstractJerseyEurekaHttpClient.java:165) ~[eureka-client-1.9.2.jar:1.9.2]at com.netflix.discovery.shared.transport.decorator.EurekaHttpClientDecorator$6.execute(EurekaHttpClientDecorator.java:137) [eureka-client-1.9.2.jar:1.9.2]at com.netflix.discovery.shared.transport.decorator.MetricsCollectingEurekaHttpClient.execute(MetricsCollectingEurekaHttpClient.java:73) ~[eureka-client-1.9.2.jar:1.9.2]at com.netflix.discovery.shared.transport.decorator.EurekaHttpClientDecorator.getApplications(EurekaHttpClientDecorator.java:134) [eureka-client-1.9.2.jar:1.9.2]at com.netflix.discovery.shared.transport.decorator.EurekaHttpClientDecorator$6.execute(EurekaHttpClientDecorator.java:137) [eureka-client-1.9.2.jar:1.9.2]at com.netflix.discovery.shared.transport.decorator.RedirectingEurekaHttpClient.executeOnNewServer(RedirectingEurekaHttpClient.java:118) ~[eureka-client-1.9.2.jar:1.9.2]at com.netflix.discovery.shared.transport.decorator.RedirectingEurekaHttpClient.execute(RedirectingEurekaHttpClient.java:79) ~[eureka-client-1.9.2.jar:1.9.2]at com.netflix.discovery.shared.transport.decorator.EurekaHttpClientDecorator.getApplications(EurekaHttpClientDecorator.java:134) [eureka-client-1.9.2.jar:1.9.2]at com.netflix.discovery.shared.transport.decorator.EurekaHttpClientDecorator$6.execute(EurekaHttpClientDecorator.java:137) [eureka-client-1.9.2.jar:1.9.2]at com.netflix.discovery.shared.transport.decorator.RetryableEurekaHttpClient.execute(RetryableEurekaHttpClient.java:120) [eureka-client-1.9.2.jar:1.9.2]at com.netflix.discovery.shared.transport.decorator.EurekaHttpClientDecorator.getApplications(EurekaHttpClientDecorator.java:134) [eureka-client-1.9.2.jar:1.9.2]at com.netflix.discovery.shared.transport.decorator.EurekaHttpClientDecorator$6.execute(EurekaHttpClientDecorator.java:137) [eureka-client-1.9.2.jar:1.9.2]at com.netflix.discovery.shared.transport.decorator.SessionedEurekaHttpClient.execute(SessionedEurekaHttpClient.java:77) [eureka-client-1.9.2.jar:1.9.2]at com.netflix.discovery.shared.transport.decorator.EurekaHttpClientDecorator.getApplications(EurekaHttpClientDecorator.java:134) [eureka-client-1.9.2.jar:1.9.2]at com.netflix.discovery.DiscoveryClient.getAndStoreFullRegistry(DiscoveryClient.java:1051) [eureka-client-1.9.2.jar:1.9.2]at com.netflix.discovery.DiscoveryClient.fetchRegistry(DiscoveryClient.java:965) [eureka-client-1.9.2.jar:1.9.2]at com.netflix.discovery.DiscoveryClient.refreshRegistry(DiscoveryClient.java:1471) [eureka-client-1.9.2.jar:1.9.2]at com.netflix.discovery.DiscoveryClient$CacheRefreshThread.run(DiscoveryClient.java:1438) [eureka-client-1.9.2.jar:1.9.2]at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511) [na:1.8.0_212]at java.util.concurrent.FutureTask.run(FutureTask.java:266) [na:1.8.0_212]at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) [na:1.8.0_212]at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624) [na:1.8.0_212]at java.lang.Thread.run(Thread.java:748) [na:1.8.0_212]2019-10-24 09:23:54.772  WARN 59687 --- [freshExecutor-0] c.n.d.s.t.d.RetryableEurekaHttpClient    : Request execution failed with message: null
2019-10-24 09:23:54.772 ERROR 59687 --- [freshExecutor-0] com.netflix.discovery.DiscoveryClient    : DiscoveryClient_PROVIDER-DEMO/192.168.1.101:provider-demo:8000 - was unable to refresh its cache! status = Cannot execute request on any known servercom.netflix.discovery.shared.transport.TransportException: Cannot execute request on any known serverat com.netflix.discovery.shared.transport.decorator.RetryableEurekaHttpClient.execute(RetryableEurekaHttpClient.java:112) ~[eureka-client-1.9.2.jar:1.9.2]at com.netflix.discovery.shared.transport.decorator.EurekaHttpClientDecorator.getApplications(EurekaHttpClientDecorator.java:134) ~[eureka-client-1.9.2.jar:1.9.2]at com.netflix.discovery.shared.transport.decorator.EurekaHttpClientDecorator$6.execute(EurekaHttpClientDecorator.java:137) ~[eureka-client-1.9.2.jar:1.9.2]at com.netflix.discovery.shared.transport.decorator.SessionedEurekaHttpClient.execute(SessionedEurekaHttpClient.java:77) ~[eureka-client-1.9.2.jar:1.9.2]at com.netflix.discovery.shared.transport.decorator.EurekaHttpClientDecorator.getApplications(EurekaHttpClientDecorator.java:134) ~[eureka-client-1.9.2.jar:1.9.2]at com.netflix.discovery.DiscoveryClient.getAndStoreFullRegistry(DiscoveryClient.java:1051) [eureka-client-1.9.2.jar:1.9.2]at com.netflix.discovery.DiscoveryClient.fetchRegistry(DiscoveryClient.java:965) [eureka-client-1.9.2.jar:1.9.2]at com.netflix.discovery.DiscoveryClient.refreshRegistry(DiscoveryClient.java:1471) [eureka-client-1.9.2.jar:1.9.2]at com.netflix.discovery.DiscoveryClient$CacheRefreshThread.run(DiscoveryClient.java:1438) [eureka-client-1.9.2.jar:1.9.2]at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511) [na:1.8.0_212]at java.util.concurrent.FutureTask.run(FutureTask.java:266) [na:1.8.0_212]at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) [na:1.8.0_212]at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624) [na:1.8.0_212]at java.lang.Thread.run(Thread.java:748) [na:1.8.0_212]