was unable to refresh its cache! status = Cannot execute request on any known server

一般报错会是这样的：

RROR [main] c.n.d.s.t.d.RedirectingEurekaHttp
Client [RedirectingEurekaHttpClient.java:83] - Request execution error
com.sun.jersey.api.client.ClientHandlerException: java.net.ConnectException: Con
nection refused:........
...
....

was unable to refresh its cache! status = 
Cannot execute request on any known server

大部分情况可以参见：

https://blog.csdn.net/feiz3020/article/details/80171839

还有一种情况就是：

则在Eureka客户端 应该配置的是eureka.client.serviceUrl.defaultZone=http://localhost:8761/eureka/

则Eureka服务端 访问地址是 http://localhost:8761/eureka/

标红的部分不要修改，保持原样，否则报错。