报错内容：
java.lang.IllegalArgumentException: no server available at com.alibaba.nacos.client.naming.net.NamingProxy.reqAPI(NamingProxy.java:438) ~[nacos-client-1.1.1.jar:na] at com.alibaba.nacos.client.naming.net.NamingProxy.reqAPI(NamingProxy.java:386) ~[nacos-client-1.1.1.jar:na] at com.alibaba.nacos.client.naming.net.NamingProxy.registerService(NamingProxy.java:188) ~[nacos-client-1.1.1.jar:na] at com.alibaba.nacos.client.naming.NacosNamingService.registerInstance(NacosNamingService.java:205) ~[nacos-client-1.1.1.jar:na] at com.alibaba.nacos.client.naming.NacosNamingService.registerInstance(NacosNamingService.java:184) ~[nacos-client-1.1.1.jar:na] at com.alibaba.cloud.nacos.registry.NacosServiceRegistry.register(NacosServiceRegistry.java:61) ~[spring-cloud-alibaba-nacos-discovery-2.1.0.RELEASE.jar:2.1.0.RELEASE] at org.springframework.cloud.client.serviceregistry.AbstractAutoServiceRegistration.register(AbstractAutoServiceRegistration.java:239) [spring-cloud-commons-2.2.2.RELEASE.jar:2.2.2.RELEASE] at com.alibaba.cloud.nacos.registry.NacosAutoServiceRegistration.register(NacosAutoServiceRegistration.java:74) [spring-cloud-alibaba-nacos-discovery-2.1.0.RELEASE.jar:2.1.0.RELEASE] at org.springframework.cloud.client.serviceregistry.AbstractAutoServiceRegistration.start(AbstractAutoServiceRegistration.java:138) [spring-cloud-commons-2.2.2.RELEASE.jar:2.2.2.RELEASE] at org.springframework.cloud.client.serviceregistry.AbstractAutoServiceRegistration.bind(AbstractAutoServiceRegistration.java:101) [spring-cloud-commons-2.2.2.RELEASE.jar:2.2.2.RELEASE] at org.springframework.cloud.client.serviceregistry.AbstractAutoServiceRegistration.onApplicationEvent(AbstractAutoServiceRegistration.java:88) [spring-cloud-commons-2.2.2.RELEASE.jar:2.2.2.RELEASE] at org.springframework.cloud.client.serviceregistry.AbstractAutoServiceRegistration.onApplicationEvent(AbstractAutoServiceRegistration.java:47) [spring-cloud-commons-2.2.2.RELEASE.jar:2.2.2.RELEASE] at org.springframework.context.event.SimpleApplicationEventMulticaster.doInvokeListener(SimpleApplicationEventMulticaster.java:172) [spring-context-5.2.4.RELEASE.jar:5.2.4.RELEASE] at org.springframework.context.event.SimpleApplicationEventMulticaster.invokeListener(SimpleApplicationEventMulticaster.java:165) [spring-context-5.2.4.RELEASE.jar:5.2.4.RELEASE] at org.springframework.context.event.SimpleApplicationEventMulticaster.multicastEvent(SimpleApplicationEventMulticaster.java:139) [spring-context-5.2.4.RELEASE.jar:5.2.4.RELEASE] at org.springframework.context.support.AbstractApplicationContext.publishEvent(AbstractApplicationContext.java:403) [spring-context-5.2.4.RELEASE.jar:5.2.4.RELEASE] at org.springframework.context.support.AbstractApplicationContext.publishEvent(AbstractApplicationContext.java:360) [spring-context-5.2.4.RELEASE.jar:5.2.4.RELEASE] at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.finishRefresh(ServletWebServerApplicationContext.java:165) [spring-boot-2.2.5.RELEASE.jar:2.2.5.RELEASE] at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:553) [spring-context-5.2.4.RELEASE.jar:5.2.4.RELEASE] at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:141) [spring-boot-2.2.5.RELEASE.jar:2.2.5.RELEASE] at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:747) [spring-boot-2.2.5.RELEASE.jar:2.2.5.RELEASE] at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:397) [spring-boot-2.2.5.RELEASE.jar:2.2.5.RELEASE] at org.springframework.boot.SpringApplication.run(SpringApplication.java:315) [spring-boot-2.2.5.RELEASE.jar:2.2.5.RELEASE] at org.springframework.boot.SpringApplication.run(SpringApplication.java:1226) [spring-boot-2.2.5.RELEASE.jar:2.2.5.RELEASE] at org.springframework.boot.SpringApplication.run(SpringApplication.java:1215) [spring-boot-2.2.5.RELEASE.jar:2.2.5.RELEASE] at com.wuyou.springcloud.UserService.main(UserService.java:11) [classes/:na]
第一种解决方案（犯错原因，粗心导致）
我的错误就在这里，百度了很久也修改了很多配置 才发现是自己写的有问题；
大家在配置nacos的配置中心的时候 注意写法（很重要）
这个两个配置不要搞混 spring.cloud.nacos.config.server-addr=127.0.0.1:8848 //在 bootstrap.properties 中配置 Nacos server 的地址和应用名 spring.cloud.nacos.discovery.server-addr=127.0.0.1:8848 //在 application.properties 中配置 Nacos server 的地址：
第二种解决方案（版本依赖冲突导致）
根据 SpringCloud Alibaba 的github的版本说明
Hoxton版本的Springcloud推荐使用Spring Cloud Alibaba Version 2.2.0.RELEASE
有兴趣的可以官网看下 ↓↓↓ 官网地址
https://github.com/alibaba/spring-cloud-alibaba/wiki/%E7%89%88%E6%9C%AC%E8%AF%B4%E6%98%8E
我的SpringCloud 版本是 Hoxton.SR3SpringCloud Alibaba的版本是
这是我的父POM里的版本
<dependency> <groupId>com.alibaba.cloud</groupId> <artifactId>spring-cloud-alibaba-dependencies</artifactId> <version>2.1.0.RELEASE</version> <type>pom</type> <scope>import</scope> </dependency>
以上配置报错 no server available 没有可用的服务器
nacos registry, cloud-user-service register failed…NacosRegistration{nacosDiscoveryProperties= NacosDiscoveryProperties{serverAddr=’’, endpoint=’’, namespace=’’, watchDelay=30000, logName=’’, service=‘cloud-user-service’, weight=1.0, clusterName=‘DEFAULT’, namingLoadCacheAtStart=‘false’, metadata={preserved.register.source=SPRING_CLOUD}, registerEnabled=true, ip=‘192.168.109.1’, networkInterface=’’, port=8001, secure=false, accessKey=’’, secretKey=’’}},
这样错误就很明显 没有对应版本依赖
我把我的父POM文件的版本改为 2.2.0.RELEASE
<dependency> <groupId>com.alibaba.cloud</groupId> <artifactId>spring-cloud-alibaba-dependencies</artifactId> <version>2.2.0.RELEASE</version> <type>pom</type> <scope>import</scope> </dependency>
成功启动啦！
Nacos的管理界面：localhostL:8848/nacos 或者 127.0.0.1:8848/那措施 默认用户名密码都是 nacos
记录自己的错误，帮助大家更快解决问题，更清楚认识问题； 加油
