nacos2.X版本无法注册的几个原因以及解决方案（踩坑避雷！）

在使用nacos＋dubbo 注册服务的时候 遇到了无法注册的问题

记录一下踩的坑以及解决方案

com.alibaba.nacos.api.exception.NacosException: Request nacos server failed:
	at com.alibaba.nacos.client.naming.remote.gprc.NamingGrpcClientProxy.requestToServer(NamingGrpcClientProxy.java:288) ~[nacos-client-2.1.0.jar:na]
	at com.alibaba.nacos.client.naming.remote.gprc.NamingGrpcClientProxy.doRegisterService(NamingGrpcClientProxy.java:128) ~[nacos-client-2.1.0.jar:na]
	at com.alibaba.nacos.client.naming.remote.gprc.NamingGrpcClientProxy.registerService(NamingGrpcClientProxy.java:114) ~[nacos-client-2.1.0.jar:na]
	at com.alibaba.nacos.client.naming.remote.NamingClientProxyDelegate.registerService(NamingClientProxyDelegate.java:94) ~[nacos-client-2.1.0.jar:na]
	at com.alibaba.nacos.client.naming.NacosNamingService.registerInstance(NacosNamingService.java:145) ~[nacos-client-2.1.0.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-3.0.2.jar:3.0.2]
	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-3.0.2.jar:3.0.2]
	at org.springframework.cloud.client.serviceregistry.AbstractAutoServiceRegistration.bind(AbstractAutoServiceRegistration.java:98) [spring-cloud-commons-3.0.2.jar:3.0.2]
	at org.springframework.cloud.client.serviceregistry.AbstractAutoServiceRegistration.onApplicationEvent(AbstractAutoServiceRegistration.java:86) [spring-cloud-commons-3.0.2.jar:3.0.2]
	at org.springframework.cloud.client.serviceregistry.AbstractAutoServiceRegistration.onApplicationEvent(AbstractAutoServiceRegistration.java:47) [spring-cloud-commons-3.0.2.jar:3.0.2]
	at org.springframework.context.event.SimpleApplicationEventMulticaster.doInvokeListener(SimpleApplicationEventMulticaster.java:176) [spring-context-5.3.12.jar:5.3.12]
	at org.springframework.context.event.SimpleApplicationEventMulticaster.invokeListener(SimpleApplicationEventMulticaster.java:169) [spring-context-5.3.12.jar:5.3.12]
	at org.springframework.context.event.SimpleApplicationEventMulticaster.multicastEvent(SimpleApplicationEventMulticaster.java:143) [spring-context-5.3.12.jar:5.3.12]
	at org.springframework.context.support.AbstractApplicationContext.publishEvent(AbstractApplicationContext.java:421) [spring-context-5.3.12.jar:5.3.12]
	at org.springframework.context.support.AbstractApplicationContext.publishEvent(AbstractApplicationContext.java:378) [spring-context-5.3.12.jar:5.3.12]
	at org.springframework.boot.web.servlet.context.WebServerStartStopLifecycle.start(WebServerStartStopLifecycle.java:46) [spring-boot-2.5.6.jar:2.5.6]
	at org.springframework.context.support.DefaultLifecycleProcessor.doStart(DefaultLifecycleProcessor.java:178) [spring-context-5.3.12.jar:5.3.12]
	at org.springframework.context.support.DefaultLifecycleProcessor.access$200(DefaultLifecycleProcessor.java:54) [spring-context-5.3.12.jar:5.3.12]
	at org.springframework.context.support.DefaultLifecycleProcessor$LifecycleGroup.start(DefaultLifecycleProcessor.java:356) [spring-context-5.3.12.jar:5.3.12]
	at java.lang.Iterable.forEach(Iterable.java:75) ~[na:1.8.0_333]
	at org.springframework.context.support.DefaultLifecycleProcessor.startBeans(DefaultLifecycleProcessor.java:155) [spring-context-5.3.12.jar:5.3.12]
	at org.springframework.context.support.DefaultLifecycleProcessor.onRefresh(DefaultLifecycleProcessor.java:123) [spring-context-5.3.12.jar:5.3.12]
	at org.springframework.context.support.AbstractApplicationContext.finishRefresh(AbstractApplicationContext.java:935) [spring-context-5.3.12.jar:5.3.12]
	at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:586) [spring-context-5.3.12.jar:5.3.12]
	at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:145) ~[spring-boot-2.5.6.jar:2.5.6]
	at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:754) ~[spring-boot-2.5.6.jar:2.5.6]
	at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:434) ~[spring-boot-2.5.6.jar:2.5.6]
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:338) ~[spring-boot-2.5.6.jar:2.5.6]
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:1343) ~[spring-boot-2.5.6.jar:2.5.6]
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:1332) ~[spring-boot-2.5.6.jar:2.5.6]
	at com.hdg.user.HdgServerUserApplication.main(HdgServerUserApplication.java:13) ~[classes/:na]
Caused by: com.alibaba.nacos.api.exception.NacosException: Client not connected, current status:STARTING
	at com.alibaba.nacos.common.remote.client.RpcClient.request(RpcClient.java:651) ~[nacos-client-2.1.0.jar:na]
	at com.alibaba.nacos.common.remote.client.RpcClient.request(RpcClient.java:631) ~[nacos-client-2.1.0.jar:na]
	at com.alibaba.nacos.client.naming.remote.gprc.NamingGrpcClientProxy.requestToServer(NamingGrpcClientProxy.java:278) ~[nacos-client-2.1.0.jar:na]
	... 32 common frames omitted

首先无法注册可能有以下几个原因：

1. nacos和dubbo版本不匹配

这是可能性最高的，首先nacos目前已经有2.X的版本了，如果使用低版本的nacos比如1.4可能会和dubbo版本产生冲突，第一次引入版本的时候我也是发现了这个问题，关于版本匹配可以到官网上查询版本对应信息。

dubbo中文官网：http://dubbo.apache.org/zh-cn/

dubbo整合nacos流程：https://cn.dubbo.apache.org/zh-cn/overview/mannual/java-sdk/reference-manual/registry/nacos/

nacos中文官网：https://nacos.io/zh-cn/index.html

这里我用的是dubbo3.0.9和nacos2.1.0,亲测是可以稳定使用的

2.开启了防火墙

如果你启动了nacos之后，nacos客户端http://部署的ip地址:8848/nacos/无法访问

那可能是开了防火墙

正常访问界面：



如果有防火墙，则需要开放相关端口（例如tcp 8848）才能使用nacos服务。

3. nacos2.X版本需额外开放端口

由于nacos2.X版本之后新增了gRPC的通信方式，因此需要增加2个端口！大坑！



如果你使用的是1.X的nacos,那只需要开放8848就行了，如果你使用的是2.X版本，那就必须要额外开放9848，9849端口。

如果你用的是docker部署nacos,那你在拉取容器做端口映射的时候就要额外映射两个端口号，这也是我之前遇到的问题。

产生错误的容器nacos启动命令（1.X版本可用）:

docker run -d --name nacos -p 8848:8848 --privileged=true --restart=always -e MODE=standalone -d nacos/nacos-server:v2.1.1

2.X版本后nacos容器启动命令：

docker run -d --name nacos -p 8848:8848 -p 9848:9848 -p 9849:9849 --privileged=true --restart=always -e MODE=standalone -d nacos/nacos-server:v2.1.1

如果你是在服务器上部署的则要去服务器上开放这两个端口

注册成功界面：

nacos客户端界面显示注册成功＜（＾－＾）＞√：