先看错误事例代码：
com.alibaba.nacos.api.exception.NacosException: failed to req API:/nacos/v1/ns/instance after all servers([nacos.com:8848]) tried: java.net.SocketTimeoutException: connect timed outat com.alibaba.nacos.client.naming.net.NamingProxy.reqApi(NamingProxy.java:556) ~[nacos-client-1.4.1.jar:na]at com.alibaba.nacos.client.naming.net.NamingProxy.reqApi(NamingProxy.java:498) ~[nacos-client-1.4.1.jar:na]at com.alibaba.nacos.client.naming.net.NamingProxy.reqApi(NamingProxy.java:493) ~[nacos-client-1.4.1.jar:na]at com.alibaba.nacos.client.naming.net.NamingProxy.registerService(NamingProxy.java:246) ~[nacos-client-1.4.1.jar:na]at com.alibaba.nacos.client.naming.NacosNamingService.registerInstance(NacosNamingService.java:212) ~[nacos-client-1.4.1.jar:na]at com.alibaba.cloud.nacos.registry.NacosServiceRegistry.register(NacosServiceRegistry.java:74) ~[spring-cloud-starter-alibaba-nacos-discovery-2021.1.jar:2021.1]at org.springframework.cloud.client.serviceregistry.AbstractAutoServiceRegistration.register(AbstractAutoServiceRegistration.java:232) [spring-cloud-commons-3.0.0.jar:3.0.0]at com.alibaba.cloud.nacos.registry.NacosAutoServiceRegistration.register(NacosAutoServiceRegistration.java:78) [spring-cloud-starter-alibaba-nacos-discovery-2021.1.jar:2021.1]at org.springframework.cloud.client.serviceregistry.AbstractAutoServiceRegistration.start(AbstractAutoServiceRegistration.java:133) [spring-cloud-commons-3.0.0.jar:3.0.0]at org.springframework.cloud.client.serviceregistry.AbstractAutoServiceRegistration.bind(AbstractAutoServiceRegistration.java:98) [spring-cloud-commons-3.0.0.jar:3.0.0]at org.springframework.cloud.client.serviceregistry.AbstractAutoServiceRegistration.onApplicationEvent(AbstractAutoServiceRegistration.java:86) [spring-cloud-commons-3.0.0.jar:3.0.0]at org.springframework.cloud.client.serviceregistry.AbstractAutoServiceRegistration.onApplicationEvent(AbstractAutoServiceRegistration.java:47) [spring-cloud-commons-3.0.0.jar:3.0.0]at org.springframework.context.event.SimpleApplicationEventMulticaster.doInvokeListener(SimpleApplicationEventMulticaster.java:172) [spring-context-5.3.2.jar:5.3.2]at org.springframework.context.event.SimpleApplicationEventMulticaster.invokeListener(SimpleApplicationEventMulticaster.java:165) [spring-context-5.3.2.jar:5.3.2]at org.springframework.context.event.SimpleApplicationEventMulticaster.multicastEvent(SimpleApplicationEventMulticaster.java:139) [spring-context-5.3.2.jar:5.3.2]at org.springframework.context.support.AbstractApplicationContext.publishEvent(AbstractApplicationContext.java:426) [spring-context-5.3.2.jar:5.3.2]at org.springframework.context.support.AbstractApplicationContext.publishEvent(AbstractApplicationContext.java:383) [spring-context-5.3.2.jar:5.3.2]at org.springframework.boot.web.servlet.context.WebServerStartStopLifecycle.start(WebServerStartStopLifecycle.java:46) [spring-boot-2.4.1.jar:2.4.1]at org.springframework.context.support.DefaultLifecycleProcessor.doStart(DefaultLifecycleProcessor.java:178) [spring-context-5.3.2.jar:5.3.2]at org.springframework.context.support.DefaultLifecycleProcessor.access$200(DefaultLifecycleProcessor.java:54) [spring-context-5.3.2.jar:5.3.2]at org.springframework.context.support.DefaultLifecycleProcessor$LifecycleGroup.start(DefaultLifecycleProcessor.java:356) [spring-context-5.3.2.jar:5.3.2]at java.lang.Iterable.forEach(Iterable.java:75) ~[na:1.8.0_144]at org.springframework.context.support.DefaultLifecycleProcessor.startBeans(DefaultLifecycleProcessor.java:155) [spring-context-5.3.2.jar:5.3.2]at org.springframework.context.support.DefaultLifecycleProcessor.onRefresh(DefaultLifecycleProcessor.java:123) [spring-context-5.3.2.jar:5.3.2]at org.springframework.context.support.AbstractApplicationContext.finishRefresh(AbstractApplicationContext.java:940) [spring-context-5.3.2.jar:5.3.2]at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:591) [spring-context-5.3.2.jar:5.3.2]at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:144) ~[spring-boot-2.4.1.jar:2.4.1]at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:767) ~[spring-boot-2.4.1.jar:2.4.1]at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:759) ~[spring-boot-2.4.1.jar:2.4.1]at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:426) ~[spring-boot-2.4.1.jar:2.4.1]at org.springframework.boot.SpringApplication.run(SpringApplication.java:326) ~[spring-boot-2.4.1.jar:2.4.1]at org.springframework.boot.SpringApplication.run(SpringApplication.java:1309) ~[spring-boot-2.4.1.jar:2.4.1]at org.springframework.boot.SpringApplication.run(SpringApplication.java:1298) ~[spring-boot-2.4.1.jar:2.4.1]at com.zj.consumer.CloudConsumerApplication.main(CloudConsumerApplication.java:15) ~[classes/:na]
这是在写springCloud项目中遇到的连接超时问题，这种问题大概率出现在yml文件中，服务地址出现错误：
图中的 server-addr是指服务地址，不能够使用nacos地址去注册，只能使用本地或者其他端口去注册
更改之后就测试成功