com.netflix.zuul.exception.ZuulException: Forwarding error

1. Problem

Spring Cloud各应用配置好并启动后, 在eureka web ui上看到都正常, 通过zuul访问一个service api, 结果报错:

com.netflix.zuul.exception.ZuulException: Forwarding error
at org.springframework.cloud.netflix.zuul.filters.route.RibbonRoutingFilter.handleException(RibbonRoutingFilter.java:189) ~[spring-cloud-netflix-core-1.4.0.RELEASE.jar:1.4.0.RELEASE]
at org.springframework.cloud.netflix.zuul.filters.route.RibbonRoutingFilter.forward(RibbonRoutingFilter.java:164) ~[spring-cloud-netflix-core-1.4.0.RELEASE.jar:1.4.0.RELEASE]
at org.springframework.cloud.netflix.zuul.filters.route.RibbonRoutingFilter.run(RibbonRoutingFilter.java:111) ~[spring-cloud-netflix-core-1.4.0.RELEASE.jar:1.4.0.RELEASE]
at com.netflix.zuul.ZuulFilter.runFilter(ZuulFilter.java:112) ~[zuul-core-1.3.0.jar:1.3.0]
at com.netflix.zuul.FilterProcessor.processZuulFilter(FilterProcessor.java:193) ~[zuul-core-1.3.0.jar:1.3.0]
at com.netflix.zuul.FilterProcessor.runFilters(FilterProcessor.java:157) ~[zuul-core-1.3.0.jar:1.3.0]
at com.netflix.zuul.FilterProcessor.route(FilterProcessor.java:118) ~[zuul-core-1.3.0.jar:1.3.0]
at com.netflix.zuul.ZuulRunner.route(ZuulRunner.java:96) ~[zuul-core-1.3.0.jar:1.3.0]
at com.netflix.zuul.http.ZuulServlet.route(ZuulServlet.java:116) ~[zuul-core-1.3.0.jar:1.3.0]
at com.netflix.zuul.http.ZuulServlet.service(ZuulServlet.java:81) ~[zuul-core-1.3.0.jar:1.3.0]
...
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) [na:1.8.0_111]
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) [tomcat-embed-core-8.5.23.jar:8.5.23]
at java.lang.Thread.run(Thread.java:745) [na:1.8.0_111]
Caused by: com.netflix.client.ClientException: null
at com.netflix.client.AbstractLoadBalancerAwareClient.executeWithLoadBalancer(AbstractLoadBalancerAwareClient.java:118) ~[ribbon-loadbalancer-2.2.4.jar:2.2.4]
at org.springframework.cloud.netflix.zuul.filters.route.support.AbstractRibbonCommand.run(AbstractRibbonCommand.java:117) ~[spring-cloud-netflix-core-1.4.0.RELEASE.jar:1.4.0.RELEASE]
at org.springframework.cloud.netflix.zuul.filters.route.support.AbstractRibbonCommand.run(AbstractRibbonCommand.java:46) ~[spring-cloud-netflix-core-1.4.0.RELEASE.jar:1.4.0.RELEASE]
at com.netflix.hystrix.HystrixCommand$2.call(HystrixCommand.java:302) ~[hystrix-core-1.5.12.jar:1.5.12]
at com.netflix.hystrix.HystrixCommand$2.call(HystrixCommand.java:298) ~[hystrix-core-1.5.12.jar:1.5.12]
...
at com.netflix.hystrix.HystrixCommand.execute(HystrixCommand.java:344) ~[hystrix-core-1.5.12.jar:1.5.12]
at org.springframework.cloud.netflix.zuul.filters.route.RibbonRoutingFilter.forward(RibbonRoutingFilter.java:158) ~[spring-cloud-netflix-core-1.4.0.RELEASE.jar:1.4.0.RELEASE]
... 67 common frames omitted
Caused by: java.lang.RuntimeException: java.net.SocketTimeoutException: Read timed out..

2. Analysis and Solution

需要等一下再call, 30s左右, eureka要在service有几次成功的heart beat后才正式服务. warming-up