启动服务配置报错

一、该问题的重现步骤是什么？

1. 

2. 

3.

二、你期待的结果是什么？实际看到的又是什么？

三、你正在使用的是什么产品，什么版本？在什么操作系统上？

bladex 2.7 centos7 

四、请提供详细的错误堆栈信息，这很重要。

2020-12-11 08:43:49.037  WARN 1 --- [           main] c.a.c.n.c.NacosPropertySourceBuilder     : Ignore the empty nacos configuration and get it based on dataId[blade-system.yaml] & group[DEFAULT_GROUP]

2020-12-11 08:43:50.037 ERROR 1 --- [           main] c.a.n.c.config.http.ServerHttpAgent      : [NACOS SocketTimeoutException httpGet] currentServerAddr:http://172.30.0.48:8848， err : connect timed out

2020-12-11 08:43:51.039 ERROR 1 --- [           main] c.a.n.c.config.http.ServerHttpAgent      : [NACOS SocketTimeoutException httpGet] currentServerAddr:http://172.30.0.48:8848， err : connect timed out

2020-12-11 08:43:52.040 ERROR 1 --- [           main] c.a.n.c.config.http.ServerHttpAgent      : [NACOS SocketTimeoutException httpGet] currentServerAddr:http://172.30.0.48:8848， err : connect timed out

2020-12-11 08:43:52.041 ERROR 1 --- [           main] c.a.n.c.config.http.ServerHttpAgent      : no available server

2020-12-11 08:43:52.041 ERROR 1 --- [           main] c.a.n.client.config.impl.ClientWorker    : [fixed-172.30.0.48_8848] [sub-server] get server config exception, dataId=blade-system-test.yaml, group=DEFAULT_GROUP, tenant=

java.net.ConnectException: no available server

        at com.alibaba.nacos.client.config.http.ServerHttpAgent.httpGet(ServerHttpAgent.java:133)

        at com.alibaba.nacos.client.config.http.MetricsHttpAgent.httpGet(MetricsHttpAgent.java:51)

        at com.alibaba.nacos.client.config.impl.ClientWorker.getServerConfig(ClientWorker.java:298)

        at com.alibaba.nacos.client.config.NacosConfigService.getConfigInner(NacosConfigService.java:149)

        at com.alibaba.nacos.client.config.NacosConfigService.getConfig(NacosConfigService.java:97)

        at com.alibaba.cloud.nacos.client.NacosPropertySourceBuilder.loadNacosData(NacosPropertySourceBuilder.java:85)

        at com.alibaba.cloud.nacos.client.NacosPropertySourceBuilder.build(NacosPropertySourceBuilder.java:74)

        at com.alibaba.cloud.nacos.client.NacosPropertySourceLocator.loadNacosPropertySource(NacosPropertySourceLocator.java:204)

        at com.alibaba.cloud.nacos.client.NacosPropertySourceLocator.loadNacosDataIfPresent(NacosPropertySourceLocator.java:191)

        at com.alibaba.cloud.nacos.client.NacosPropertySourceLocator.loadApplicationConfiguration(NacosPropertySourceLocator.java:150)

        at com.alibaba.cloud.nacos.client.NacosPropertySourceLocator.locate(NacosPropertySourceLocator.java:103)

        at org.springframework.cloud.bootstrap.config.PropertySourceLocator.locateCollection(PropertySourceLocator.java:52)

五、若有更多详细信息，请在下面提供。