@Test
	public void testRoundRobin(){
		Set<String> servers = new HashSet<String>();
		System.out.println("Simple Round Robin Test");
		for (int i=0; i < 9; i++){
			Server svc = lb.chooseServer("user1");
			servers.add(svc.getId());
		}
		assertEquals(isAliveMap.keySet(), servers);
		System.out.println("Round Robin Test With Server SERVER DOWN");
		isAliveMap.put("dummyservice2.netflix.com:8080", Boolean.FALSE);
		((BaseLoadBalancer)lb).markServerDown("dummyservice2.netflix.com:8080");
		try {
		    Thread.sleep(3000);
		} catch (Exception e) { // NOPMD			
		}
		for (int i=0; i < 12; i++){
			Server svc = lb.chooseServer("user1");
			assertNotNull(svc);
			System.out.println("server: " + svc.getHost());
			assertFalse(svc.getId().equals("dummyservice2.netflix.com:8080"));
		}
	}
Simulate a single user who should just round robin among the available servers
ribbon-loadbalancer/src/test/java/com/netflix/loadbalancer/SimpleRoundRobinLBTest.java