做谷粒商城练习时P46，发现网关gateway转发到renren-fast获取验证码报503，原因是我在commom模块里引入的nacos排除了ribbon，所以无法通过lb路由到指定微服务
<dependency>
<groupId>com.alibaba.cloud</groupId>
<artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId>
<exclusions>
<exclusion>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-netflix-ribbon</artifactId>
</exclusion>
</exclusions>
</dependency>
解决方法：在gateway里引入loadbalancer依赖
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-loadbalancer</artifactId>
</dependency>
