title: Spring Cloud with Zuul and Eureka cannot handle service instances going down
body: <p>I'm currently having an issue when using Netflix Eureka and Zuul in a Spring Cloud environment using Docker. </p>
  
  <p>My current setup is as follows: 3 Docker containers:</p>
  
  <ul>
  <li>a Eureka server</li>
  <li>a Zuul server that uses Eureka to map routes to services and load balancing between multiple containers of the same service.</li>
  <li>a service (currently just returning a simple string)</li>
  </ul>
  
  <p>This setup works fine but troubles begin when I start playing with the scaling of the service.
  When I scale up, Zuul picks up the new servers after 30 seconds. That's fine by me. However, when I take down service containers, calls to Zuul can fail (with a HTTP errorcode 200!) because Zuul still thinks the servers are in the alive pool. </p>
  
  <p>I'm using Spring Boot 1.3.6 and Spring Cloud 1.1.2</p>
  
  <p>My questions:</p>
  
  <ul>
  <li>Can Zuul be configured to retry calls?</li>
  <li>Is there a way to force Zuul to do a ping to all the servers using a REST call? As far as I can see, there is no Spring Cloud endpoint for this. Posting to /routes doesn't do what I want. </li>
  <li>If that's not possible, can Zuul be configured to actually send something else than a 200 when a server is not responding in time?</li>
  </ul>