请问下客户端调用超时是什么问题？

[chencore]

2018-02-01 11:21:33.101  INFO 21868 --- [erListUpdater-0] c.netflix.config.ChainedDynamicProperty  : Flipping property: PROVIDER-SERVICE.ribbon.ActiveConnectionsLimit to use NEXT property: niws.loadbalancer.availabilityFilteringRule.activeConnectionsLimit = 2147483647
2018-02-01 11:21:53.448 ERROR 21868 --- [nio-8081-exec-1] o.a.c.c.C.[.[.[/].[dispatcherServlet]    : Servlet.service() for servlet [dispatcherServlet] in context with path [] threw exception [Request processing failed; nested exception is org.springframework.web.client.ResourceAccessException: I/O error on GET request for "http://PROVIDER-SERVICE/provider": Connection timed out: connect; nested exception is java.net.ConnectException: Connection timed out: connect] with root cause

java.net.ConnectException: Connection timed out: connect
	at java.net.DualStackPlainSocketImpl.connect0(Native Method) ~[na:1.8.0_144]

[JeffLi1993]

注册中心没有启动