public void verifyEntriesAfterFailover() {
    final Region r = cache.getRegion(SEPARATOR + regionName);
    assertNotNull(r);
    WaitCriterion ev = new WaitCriterion() {
      @Override
      public boolean done() {
        return !r.getEntry("key-5").getValue().equals("key-5");
      }

      @Override
      public String description() {
        return null;
      }
    };
    GeodeAwaitility.await().untilAsserted(ev);
    assertEquals("value-5", r.getEntry("key-5").getValue());
    assertEquals("value-4", r.getEntry("key-4").getValue());
  }
Dunit test to verify HA feature. Have 2 nodes S1 & S2. Client is connected to S1 & S2 with S1 as
the primary end point. Do some puts on S1 .The expiry is on high side. Stop S1 , the client is
failing to S2.During fail over duration do some puts on S1. The client on failing to S2 may
receive duplicate events but should not miss any events.
geode-core/src/distributedTest/java/org/apache/geode/internal/cache/ha/FailoverDistributedTest.java