版本信息：

<spring-cloud.version>Hoxton.RELEASE</spring-cloud.version>
<spring-cloud-alibaba.version>2.2.0.RELEASE</spring-cloud-alibaba.version>
告警信息：
2020-04-05 11:05:48.904 WARN 5898 --- [ main] org.apache.dubbo.config.AbstractConfig : [DUBBO] Connection refused (Connection refused), dubbo version: 2.7.4.1, current host: 192.168.3.8

java.net.ConnectException: Connection refused (Connection refused)
at java.net.PlainSocketImpl.socketConnect(Native Method) ~[na:1.8.0_221]
at java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:350) ~[na:1.8.0_221]
at java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:206) ~[na:1.8.0_221]
at java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:188) ~[na:1.8.0_221]
at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:392) ~[na:1.8.0_221]
at java.net.Socket.connect(Socket.java:589) ~[na:1.8.0_221]
at org.apache.dubbo.config.ServiceConfig.findConfigedHosts(ServiceConfig.java:704) [dubbo-2.7.4.1.jar:2.7.4.1]
at org.apache.dubbo.config.ServiceConfig.doExportUrlsFor1Protocol(ServiceConfig.java:561) [dubbo-2.7.4.1.jar:2.7.4.1]
at org.apache.dubbo.config.ServiceConfig.doExportUrls(ServiceConfig.java:458) [dubbo-2.7.4.1.jar:2.7.4.1]
at org.apache.dubbo.config.ServiceConfig.doExport(ServiceConfig.java:416) [dubbo-2.7.4.1.jar:2.7.4.1]
at org.apache.dubbo.config.ServiceConfig.export(ServiceConfig.java:379) [dubbo-2.7.4.1.jar:2.7.4.1]
at com.alibaba.cloud.dubbo.service.DubboMetadataServiceExporter.export(DubboMetadataServiceExporter.java:82) [spring-cloud-alibaba-dubbo-2.2.0.RELEASE.jar:2.2.0.RELEASE]
at com.alibaba.cloud.dubbo.metadata.repository.DubboServiceMetadataRepository.getDubboMetadataServiceMetadata(DubboServiceMetadataRepository.java:318) [spring-cloud-alibaba-dubbo-2.2.0.RELEASE.jar:2.2.0.RELEASE]
at com.alibaba.cloud.dubbo.metadata.repository.DubboServiceMetadataRepository$$FastClassBySpringCGLIB$$4ef4b7bd.invoke() [spring-cloud-alibaba-dubbo-2.2.0.RELEASE.jar:2.2.0.RELEASE]
at org.springframework.cglib.proxy.MethodProxy.invoke(MethodProxy.java:218) [spring-core-5.2.1.RELEASE.jar:5.2.1.RELEASE]
at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.invokeJoinpoint(CglibAopProxy.java:769) [spring-aop-5.2.1.RELEASE.jar:5.2.1.RELEASE]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:163) [spring-aop-5.2.1.RELEASE.jar:5.2.1.RELEASE]
at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.proceed(CglibAopProxy.java:747) [spring-aop-5.2.1.RELEASE.jar:5.2.1.RELEASE]
at org.springframework.dao.support.PersistenceExceptionTranslationInterceptor.invoke(PersistenceExceptionTranslationInterceptor.java:139) [spring-tx-5.2.1.RELEASE.jar:5.2.1.RELEASE]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186) [spring-aop-5.2.1.RELEASE.jar:5.2.1.RELEASE]
at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.proceed(CglibAopProxy.java:747) [spring-aop-5.2.1.RELEASE.jar:5.2.1.RELEASE]
at org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:689) [spring-aop-5.2.1.RELEASE.jar:5.2.1.RELEASE]
at com.alibaba.cloud.dubbo.metadata.repository.DubboServiceMetadataRepository$$EnhancerBySpringCGLIB$$12b03d41.getDubboMetadataServiceMetadata() [spring-cloud-alibaba-dubbo-2.2.0.RELEASE.jar:2.2.0.RELEASE]
at com.alibaba.cloud.dubbo.autoconfigure.DubboServiceRegistrationAutoConfiguration.attachDubboMetadataServiceMetadata(DubboServiceRegistrationAutoConfiguration.java:127) [spring-cloud-alibaba-dubbo-2.2.0.RELEASE.jar:2.2.0.RELEASE]
at com.alibaba.cloud.dubbo.autoconfigure.DubboServiceRegistrationAutoConfiguration.attachDubboMetadataServiceMetadata(DubboServiceRegistrationAutoConfiguration.java:121) [spring-cloud-alibaba-dubbo-2.2.0.RELEASE.jar:2.2.0.RELEASE]
at com.alibaba.cloud.dubbo.autoconfigure.DubboServiceRegistrationAutoConfiguration.onServiceInstancePreRegistered(DubboServiceRegistrationAutoConfiguration.java:112) [spring-cloud-alibaba-dubbo-2.2.0.RELEASE.jar:2.2.0.RELEASE]
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_221]
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_221]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_221]
at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_221]
at org.springframework.context.event.ApplicationListenerMethodAdapter.doInvoke(ApplicationListenerMethodAdapter.java:300) [spring-context-5.2.1.RELEASE.jar:5.2.1.RELEASE]
at org.springframework.context.event.ApplicationListenerMethodAdapter.processEvent(ApplicationListenerMethodAdapter.java:190) [spring-context-5.2.1.RELEASE.jar:5.2.1.RELEASE]
at org.springframework.context.event.ApplicationListenerMethodAdapter.onApplicationEvent(ApplicationListenerMethodAdapter.java:153) [spring-context-5.2.1.RELEASE.jar:5.2.1.RELEASE]
at org.springframework.context.event.SimpleApplicationEventMulticaster.doInvokeListener(SimpleApplicationEventMulticaster.java:172) [spring-context-5.2.1.RELEASE.jar:5.2.1.RELEASE]
at org.springframework.context.event.SimpleApplicationEventMulticaster.invokeListener(SimpleApplicationEventMulticaster.java:165) [spring-context-5.2.1.RELEASE.jar:5.2.1.RELEASE]
at org.springframework.context.event.SimpleApplicationEventMulticaster.multicastEvent(SimpleApplicationEventMulticaster.java:139) [spring-context-5.2.1.RELEASE.jar:5.2.1.RELEASE]
at org.springframework.context.support.AbstractApplicationContext.publishEvent(AbstractApplicationContext.java:403) [spring-context-5.2.1.RELEASE.jar:5.2.1.RELEASE]
at org.springframework.context.support.AbstractApplicationContext.publishEvent(AbstractApplicationContext.java:360) [spring-context-5.2.1.RELEASE.jar:5.2.1.RELEASE]
at com.alibaba.cloud.dubbo.registry.DubboServiceRegistrationEventPublishingAspect.beforeRegister(DubboServiceRegistrationEventPublishingAspect.java:51) [spring-cloud-alibaba-dubbo-2.2.0.RELEASE.jar:2.2.0.RELEASE]
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_221]
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_221]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_221]
at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_221]
at org.springframework.aop.aspectj.AbstractAspectJAdvice.invokeAdviceMethodWithGivenArgs(AbstractAspectJAdvice.java:644) [spring-aop-5.2.1.RELEASE.jar:5.2.1.RELEASE]
at org.springframework.aop.aspectj.AbstractAspectJAdvice.invokeAdviceMethod(AbstractAspectJAdvice.java:626) [spring-aop-5.2.1.RELEASE.jar:5.2.1.RELEASE]
at org.springframework.aop.aspectj.AspectJMethodBeforeAdvice.before(AspectJMethodBeforeAdvice.java:44) [spring-aop-5.2.1.RELEASE.jar:5.2.1.RELEASE]
at org.springframework.aop.framework.adapter.MethodBeforeAdviceInterceptor.invoke(MethodBeforeAdviceInterceptor.java:55) [spring-aop-5.2.1.RELEASE.jar:5.2.1.RELEASE]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:175) [spring-aop-5.2.1.RELEASE.jar:5.2.1.RELEASE]
at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.proceed(CglibAopProxy.java:747) [spring-aop-5.2.1.RELEASE.jar:5.2.1.RELEASE]
at org.springframework.aop.aspectj.AspectJAfterAdvice.invoke(AspectJAfterAdvice.java:47) [spring-aop-5.2.1.RELEASE.jar:5.2.1.RELEASE]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:175) [spring-aop-5.2.1.RELEASE.jar:5.2.1.RELEASE]
at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.proceed(CglibAopProxy.java:747) [spring-aop-5.2.1.RELEASE.jar:5.2.1.RELEASE]
at org.springframework.aop.interceptor.ExposeInvocationInterceptor.invoke(ExposeInvocationInterceptor.java:93) [spring-aop-5.2.1.RELEASE.jar:5.2.1.RELEASE]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186) [spring-aop-5.2.1.RELEASE.jar:5.2.1.RELEASE]
at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.proceed(CglibAopProxy.java:747) [spring-aop-5.2.1.RELEASE.jar:5.2.1.RELEASE]
at org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:689) [spring-aop-5.2.1.RELEASE.jar:5.2.1.RELEASE]
at com.alibaba.cloud.nacos.registry.NacosServiceRegistry$$EnhancerBySpringCGLIB$$4a17a215.register() [spring-cloud-alibaba-nacos-discovery-2.2.0.RELEASE.jar:2.2.0.RELEASE]
at org.springframework.cloud.client.serviceregistry.AbstractAutoServiceRegistration.register(AbstractAutoServiceRegistration.java:239) [spring-cloud-commons-2.2.0.RELEASE.jar:2.2.0.RELEASE]
at com.alibaba.cloud.nacos.registry.NacosAutoServiceRegistration.register(NacosAutoServiceRegistration.java:76) [spring-cloud-alibaba-nacos-discovery-2.2.0.RELEASE.jar:2.2.0.RELEASE]
at org.springframework.cloud.client.serviceregistry.AbstractAutoServiceRegistration.start(AbstractAutoServiceRegistration.java:138) [spring-cloud-commons-2.2.0.RELEASE.jar:2.2.0.RELEASE]
at org.springframework.cloud.client.serviceregistry.AbstractAutoServiceRegistration.bind(AbstractAutoServiceRegistration.java:101) [spring-cloud-commons-2.2.0.RELEASE.jar:2.2.0.RELEASE]
at org.springframework.cloud.client.serviceregistry.AbstractAutoServiceRegistration.onApplicationEvent(AbstractAutoServiceRegistration.java:88) [spring-cloud-commons-2.2.0.RELEASE.jar:2.2.0.RELEASE]
at org.springframework.cloud.client.serviceregistry.AbstractAutoServiceRegistration.onApplicationEvent(AbstractAutoServiceRegistration.java:47) [spring-cloud-commons-2.2.0.RELEASE.jar:2.2.0.RELEASE]
at org.springframework.context.event.SimpleApplicationEventMulticaster.doInvokeListener(SimpleApplicationEventMulticaster.java:172) [spring-context-5.2.1.RELEASE.jar:5.2.1.RELEASE]
at org.springframework.context.event.SimpleApplicationEventMulticaster.invokeListener(SimpleApplicationEventMulticaster.java:165) [spring-context-5.2.1.RELEASE.jar:5.2.1.RELEASE]
at org.springframework.context.event.SimpleApplicationEventMulticaster.multicastEvent(SimpleApplicationEventMulticaster.java:139) [spring-context-5.2.1.RELEASE.jar:5.2.1.RELEASE]
at org.springframework.context.support.AbstractApplicationContext.publishEvent(AbstractApplicationContext.java:403) [spring-context-5.2.1.RELEASE.jar:5.2.1.RELEASE]
at org.springframework.context.support.AbstractApplicationContext.publishEvent(AbstractApplicationContext.java:360) [spring-context-5.2.1.RELEASE.jar:5.2.1.RELEASE]
at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.finishRefresh(ServletWebServerApplicationContext.java:165) [spring-boot-2.2.1.RELEASE.jar:2.2.1.RELEASE]
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:553) [spring-context-5.2.1.RELEASE.jar:5.2.1.RELEASE]
at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:141) [spring-boot-2.2.1.RELEASE.jar:2.2.1.RELEASE]
at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:747) [spring-boot-2.2.1.RELEASE.jar:2.2.1.RELEASE]
at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:397) [spring-boot-2.2.1.RELEASE.jar:2.2.1.RELEASE]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:315) [spring-boot-2.2.1.RELEASE.jar:2.2.1.RELEASE]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1226) [spring-boot-2.2.1.RELEASE.jar:2.2.1.RELEASE]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1215) [spring-boot-2.2.1.RELEASE.jar:2.2.1.RELEASE]
at com.zhuzhi.alibaba.cloud.provider.ProviderApplication.main(ProviderApplication.java:17) [classes/:na]