WARN  c.n.d.s.transport.decorator.RetryableEurekaHttpClient
                                                - Request execution failed with message: java.net.ConnectException: 拒绝连接
2019-07-22 10:46:14.402 [DiscoveryClient-HeartbeatExecutor-0] ERROR com.netflix.discovery.DiscoveryClient
                                                - DiscoveryClient_PATH-SERVICE/app04:path-service:8830 - was unable to send heartbeat!
com.netflix.discovery.shared.transport.TransportException: Cannot execute request on any known server

Caused by: com.fasterxml.jackson.databind.exc.MismatchedInputException: Root name 'timestamp' does not match expected ('instance') for type [simple type, class com.netflix.appinfo.InstanceInfo]
 at [Source: (com.sun.jersey.client.apache4.ApacheHttpClient4Handler$HttpClientResponseInputStream); line: 1, column: 2]
        at com.fasterxml.jackson.databind.exc.MismatchedInputException.from(MismatchedInputException.java:59)

解决：

• eureka.client.serviceUrl.defaultZone=http://eureka:eureka@localhost:8761/ 改为
• eureka.client.serviceUrl.defaultZone=http://eureka:eureka@localhost:8761/eureka
• 注意，浏览器访问不需要eureka，但配置必须要！