public static void registerK1AndK2OnPrimaryAndSecondaryAndVerifyResponse() {
    ServerLocation primary = pool.getPrimary();
    ServerLocation secondary = pool.getRedundants().get(0);
    LocalRegion r = (LocalRegion) cache.getRegion(SEPARATOR + REGION_NAME);
    assertNotNull(r);
    ServerRegionProxy srp = new ServerRegionProxy(r);
    List list = new ArrayList();
    list.add(k1);
    list.add(k2);

    // Primary server
    List serverKeys1 = srp.registerInterestOn(primary, list, InterestType.KEY,
        InterestResultPolicy.KEYS, false, r.getAttributes().getDataPolicy());
    assertNotNull(serverKeys1);
    // expect serverKeys in response from primary
    List resultKeys = (List) serverKeys1.get(0);
    assertEquals(2, resultKeys.size());
    assertTrue(resultKeys.contains(k1));
    assertTrue(resultKeys.contains(k2));

    // Secondary server
    List serverKeys2 = srp.registerInterestOn(secondary, list, InterestType.KEY,
        InterestResultPolicy.KEYS, false, r.getAttributes().getDataPolicy());
    // if the list is null then it is empty
    if (serverKeys2 != null) {
      // no serverKeys in response from secondary
      assertTrue(serverKeys2.isEmpty());
    }
  }
returns the secondary that was stopped
geode-core/src/distributedTest/java/org/apache/geode/internal/cache/tier/sockets/HAInterestTestCase.java