在搭建springcloud eureka服务端和一个spring cloud config服务端 时 先启动了config服务器 在启动eureka服务器 

这时eureka启动报错，

com.netflix.discovery.shared.transport.TransportException: Cannot execute request on any known server
	at com.netflix.discovery.shared.transport.decorator.RetryableEurekaHttpClient.execute(RetryableEurekaHttpClient.java:111) ~[eureka-client-1.6.2.jar:1.6.2]
	at com.netflix.discovery.shared.transport.decorator.EurekaHttpClientDecorator.register(EurekaHttpClientDecorator.java:56) ~[eureka-client-1.6.2.jar:1.6.2]
	at com.netflix.discovery.shared.transport.decorator.EurekaHttpClientDecorator$1.execute(EurekaHttpClientDecorator.java:59) ~[eureka-client-1.6.2.jar:1.6.2]
	at com.netflix.discovery.shared.transport.decorator.SessionedEurekaHttpClient.execute(SessionedEurekaHttpClient.java:77) ~[eureka-client-1.6.2.jar:1.6.2]
	at com.netflix.discovery.shared.transport.decorator.EurekaHttpClientDecorator.register(EurekaHttpClientDecorator.java:56) ~[eureka-client-1.6.2.jar:1.6.2]
	at com.netflix.discovery.DiscoveryClient.register(DiscoveryClient.java:798) ~[eureka-client-1.6.2.jar:1.6.2]
	at com.netflix.discovery.InstanceInfoReplicator.run(InstanceInfoReplicator.java:104) [eureka-client-1.6.2.jar:1.6.2]
	at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511) [na:1.8.0_221]
	at java.util.concurrent.FutureTask.run(FutureTask.java:266) [na:1.8.0_221]
	at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$201(ScheduledThreadPoolExecutor.java:180) [na:1.8.0_221]
	at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:293) [na:1.8.0_221]
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) [na:1.8.0_221]
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624) [na:1.8.0_221]
	at java.lang.Thread.run(Thread.java:748) [na:1.8.0_221]

通过排查 原因是自己yml文件写错了。

修改成bootstrap.yml 就可以了