title: Problems with Eureka server
body: <p>I have a local eureka server and one client</p>
  
  <p>Eureka:</p>
  
  <pre><code>server:
   port: 1111
  
  eureka:
   instance:
     prefer-ip-address: true
   client:
     registerWithEureka: false
     fetchRegistry: false
     serviceUrl:
        defaultZone: http://127.0.0.1:1111/eureka/
   server:
     waitTimeInMsWhenSyncEmpty: 0    
  </code></pre>
  
  <p>Client:</p>
  
  <pre><code>eureka:
    instance:
      prefer-ip-address: true
    client:
      serviceUrl:
      defaultZone: http://127.0.0.1:1111/eureka/
  </code></pre>
  
  <p>I have 2 problems:</p>
  
  <p>1) Eureka server throws in log: </p>
  
  <blockquote>
    <p>NullPointerException: 
        at com.netflix.eureka.resources.StatusResource.isReplicaAvailable</p>
  </blockquote>
  
  <p>2) The client connecting with Eureka, but after some time I see in his log next:</p>
  
  <blockquote>
    <p>RedirectingEurekaHttpClient  : Request execution error
    javax.ws.rs.WebApplicationException: null at com.netflix.discovery.provider.DiscoveryJerseyProvider.readFrom(DiscoveryJerseyProvider.java:110)</p>
    
    <p>RetryableEurekaHttpClient    : Request execution failure
    DiscoveryClient    : DiscoveryClient_MW/192.168.0.100:client:8080 - was unable to send heartbeat!</p>
    
    <p>com.netflix.discovery.shared.transport.TransportException: Cannot execute request on any known server</p>
  </blockquote>
  
  <p>In log Eureka I see:</p>
  
  <blockquote>
    <p>InstanceRegistry      : DS: Registry: lease doesn't exist, registering resource: CLIENT - 192.168.0.100:client:8080
    InstanceResource    : Not Found (Renew): CLIENT - 192.168.0.100:client:8080</p>
  </blockquote>
  
  <p>In Eureka web console the client has a UP status, but also there is a big inscription: <br/></p>
  
  <blockquote>
    <p>RENEWALS ARE LESSER THAN THE THRESHOLD. THE SELF PRESERVATION MODE IS
    TURNED OFF.THIS MAY NOT PROTECT INSTANCE EXPIRY IN CASE OF
    NETWORK/OTHER PROBLEM</p>
  </blockquote>
  
  <p>Although connection is working and I can get link to my client throught Eureka.</p>
  
  <p>Could you explain what it means and how I can get rid from that?</p>