1.Fegin消费端调用注册中心注册的服务

java.util.concurrent.TimeoutException: null
    at com.netflix.hystrix.AbstractCommand.handleTimeoutViaFallback(AbstractCommand.java:997) ~[hystrix-core-1.5.12.jar:1.5.12]
    at com.netflix.hystrix.AbstractCommand.access$500(AbstractCommand.java:60) ~[hystrix-core-1.5.12.jar:1.5.12]
    at com.netflix.hystrix.AbstractCommand$12.call(AbstractCommand.java:610) ~[hystrix-core-1.5.12.jar:1.5.12]
    at com.netflix.hystrix.AbstractCommand$12.call(AbstractCommand.java:601) ~[hystrix-core-1.5.12.jar:1.5.12]
    at rx.internal.operators.OperatorOnErrorResumeNextViaFunction$4.onError(OperatorOnErrorResumeNextViaFunction.java:140) ~[rxjava-1.1.10.jar:1.1.10]
    at rx.internal.operators.OnSubscribeDoOnEach$DoOnEachSubscriber.onError(OnSubscribeDoOnEach.java:87) ~[rxjava-1.1.10.jar:1.1.10]
    at rx.internal.operators.OnSubscribeDoOnEach$DoOnEachSubscriber.onError(OnSubscribeDoOnEach.java:87) ~[rxjava-1.1.10.jar:1.1.10]
    at com.netflix.hystrix.AbstractCommand$HystrixObservableTimeoutOperator$1$1.run(AbstractCommand.java:1154) ~[hystrix-core-1.5.12.jar:1.5.12]
    at com.netflix.hystrix.strategy.concurrency.HystrixContextRunnable$1.call(HystrixContextRunnable.java:45) ~[hystrix-core-1.5.12.jar:1.5.12]
    at com.netflix.hystrix.strategy.concurrency.HystrixContextRunnable$1.call(HystrixContextRunnable.java:41) ~[hystrix-core-1.5.12.jar:1.5.12]
    at com.netflix.hystrix.strategy.concurrency.HystrixContextRunnable.run(HystrixContextRunnable.java:61) ~[hystrix-core-1.5.12.jar:1.5.12]
    at com.netflix.hystrix.AbstractCommand$HystrixObservableTimeoutOperator$1.tick(AbstractCommand.java:1159) ~[hystrix-core-1.5.12.jar:1.5.12]
    at com.netflix.hystrix.util.HystrixTimer$1.run(HystrixTimer.java:99) ~[hystrix-core-1.5.12.jar:1.5.12]
    at java.util.concurrent.Executors$RunnableAdapter.call$$$capture(Executors.java:511) ~[na:1.8.0_151]
    at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java) ~[na:1.8.0_151]
    at java.util.concurrent.FutureTask.runAndReset(FutureTask.java:308) ~[na:1.8.0_151]
    at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$301(ScheduledThreadPoolExecutor.java:180) ~[na:1.8.0_151]
    at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:294) ~[na:1.8.0_151]
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) ~[na:1.8.0_151]
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624) ~[na:1.8.0_151]
    at java.lang.Thread.run(Thread.java:748) [na:1.8.0_151]

解决方式：

消费端需要添加fallback
@FeignClient(name = "service-user", fallback = DcClientFallback.class)

2.Fegin默认未开启Hystric服务调用异常

com.netflix.client.ClientException: Load balancer does not have available server for client: service-user
    at com.netflix.loadbalancer.LoadBalancerContext.getServerFromLoadBalancer(LoadBalancerContext.java:483) ~[ribbon-loadbalancer-2.2.2.jar:2.2.2]
    at com.netflix.loadbalancer.reactive.LoadBalancerCommand$1.call(LoadBalancerCommand.java:184) ~[ribbon-loadbalancer-2.2.2.jar:2.2.2]
    at com.netflix.loadbalancer.reactive.LoadBalancerCommand$1.call(LoadBalancerCommand.java:180) ~[ribbon-loadbalancer-2.2.2.jar:2.2.2]
    at rx.Observable.unsafeSubscribe(Observable.java:10211) ~[rxjava-1.1.10.jar:1.1.10]
    at rx.internal.operators.OnSubscribeConcatMap.call(OnSubscribeConcatMap.java:94) ~[rxjava-1.1.10.jar:1.1.10]
    at rx.internal.operators.OnSubscribeConcatMap.call(OnSubscribeConcatMap.java:42) ~[rxjava-1.1.10.jar:1.1.10]
    at rx.internal.operators.OnSubscribeLift.call(OnSubscribeLift.java:48) ~[rxjava-1.1.10.jar:1.1.10]
    at rx.internal.operators.OnSubscribeLift.call(OnSubscribeLift.java:30) ~[rxjava-1.1.10.jar:1.1.10]
    at rx.internal.operators.OnSubscribeLift.call(OnSubscribeLift.java:48) ~[rxjava-1.1.10.jar:1.1.10]
    at rx.internal.operators.OnSubscribeLift.call(OnSubscribeLift.java:30) ~[rxjava-1.1.10.jar:1.1.10]
    at rx.Observable.subscribe(Observable.java:10307) ~[rxjava-1.1.10.jar:1.1.10]
    at rx.Observable.subscribe(Observable.java:10274) ~[rxjava-1.1.10.jar:1.1.10]
    at rx.observables.BlockingObservable.blockForSingle(BlockingObservable.java:445) ~[rxjava-1.1.10.jar:1.1.10]
    at rx.observables.BlockingObservable.single(BlockingObservable.java:342) ~[rxjava-1.1.10.jar:1.1.10]
    at com.netflix.client.AbstractLoadBalancerAwareClient.executeWithLoadBalancer(AbstractLoadBalancerAwareClient.java:117) ~[ribbon-loadbalancer-2.2.2.jar:2.2.2]
    at org.springframework.cloud.netflix.feign.ribbon.LoadBalancerFeignClient.execute(LoadBalancerFeignClient.java:63) ~[spring-cloud-netflix-core-1.3.1.RELEASE.jar:1.3.1.RELEASE]
    at feign.SynchronousMethodHandler.executeAndDecode(SynchronousMethodHandler.java:97) ~[feign-core-9.5.0.jar:na]
    at feign.SynchronousMethodHandler.invoke(SynchronousMethodHandler.java:76) ~[feign-core-9.5.0.jar:na]
    at feign.ReflectiveFeign$FeignInvocationHandler.invoke(ReflectiveFeign.java:103) ~[feign-core-9.5.0.jar:na]
    at com.sun.proxy.$Proxy93.consumer(Unknown Source) ~[na:na]
    at com.tim.controller.dc.DcController.dc(DcController.java:18) ~[classes/:na]
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_151]
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_151]
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_151]
    at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_151]
    at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:205) ~[spring-web-4.3.9.RELEASE.jar:4.3.9.RELEASE]
    at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:133) ~[spring-web-4.3.9.RELEASE.jar:4.3.9.RELEASE]
    at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:97) ~[spring-webmvc-4.3.9.RELEASE.jar:4.3.9.RELEASE]
    at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:827) ~[spring-webmvc-4.3.9.RELEASE.jar:4.3.9.RELEASE]
    at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:738) ~[spring-webmvc-4.3.9.RELEASE.jar:4.3.9.RELEASE]
    at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:85) ~[spring-webmvc-4.3.9.RELEASE.jar:4.3.9.RELEASE]
    at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:967) ~[spring-webmvc-4.3.9.RELEASE.jar:4.3.9.RELEASE]
    at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:901) ~[spring-webmvc-4.3.9.RELEASE.jar:4.3.9.RELEASE]
    at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:970) ~[spring-webmvc-4.3.9.RELEASE.jar:4.3.9.RELEASE]
    at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:861) ~[spring-webmvc-4.3.9.RELEASE.jar:4.3.9.RELEASE]
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:635) ~[tomcat-embed-core-8.5.15.jar:8.5.15]
    at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:846) ~[spring-webmvc-4.3.9.RELEASE.jar:4.3.9.RELEASE]
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:742) ~[tomcat-embed-core-8.5.15.jar:8.5.15]

原因1：(服务消费方未引入Eureka包)

feign:
  hystrix:
    enabled: true

3.启动独立的服务（该服务有调用底层类操作数据库）

image.png

原因：springboot启动时会自动注入数据源和配置jpa
解决办法一：

启动类中加入注解：@SpringBootApplication(exclude={DataSourceAutoConfiguration.class,HibernateJpaAutoConfiguration.class})

解决办法二：

在Application.properties文件内配置数据源即可。代码如下：
spring.datasource.url=jdbc:mysql://localhost:3306/test
spring.datasource.username=root
spring.datasource.password=123456
spring.datasource.driver-class-name=com.mysql.jdbc.Driver
spring.datasource.max-idle=10
spring.datasource.max-wait=10000
spring.datasource.min-idle=5
spring.datasource.initial-size=5

后发现在数据库配置相关必须在独立的服务上配置

4.GateWay网关服务zuul API调用超时问题

image.png

只需要在配置文件添加如下配置即可:

properties配置文件:

zuul.host.socket-timeout-millis=60000
zuul.host.connect-timeout-millis=10000
hystrix.command.default.execution.isolation.thread.timeoutInMilliseconds=60000

yml配置文件：

zuul:
    host:
        connect-timeout-millis: 10000
        socket-timeout-millis: 60000

hystrix:
    command:
        default:
            execution:
                isolation:
                    thread:
                        timeoutInMilliseconds: 60000

4.GateWay网关服务zuul API调用异常Ribbon超时

image.png

properties配置文件:

ribbon.ConnectTimeout=30000
ribbon.ReadTimeout=30000

yml配置文件：

ribbon:
  ReadTimeout: 30000
  ConnectTimeout: 30000

5.Eureka启动连接异常

image.png

原因：
Eureka自己配置了默认的注册中心地址

image.png

解决方式配置注册中心地址覆盖默认地址

eureka:
  client:
    registerWithEureka: false  #false:不作为一个客户端注册到注册中心
    fetchRegistry: false
  serviceUrl:
    defaultZone: http://127.0.0.1:1001