@Override
	public String getInstanceId() {
		if (this.instanceId == null && this.metadataMap != null) {
			return this.metadataMap.get("instanceId");
		}
		return this.instanceId;
	}
Initial status to register with remote Eureka server.
spring-cloud-netflix-eureka-client/src/main/java/org/springframework/cloud/netflix/eureka/EurekaInstanceConfigBean.java