@Test
  public void testGetEntry() {
    Host host = Host.getHost(0);
    // VM accessor = host.getVM(0);
    VM datastore = host.getVM(1);
    VM client = host.getVM(2);

    int port = createRegionsAndStartServer(datastore, false);
    createClientRegion(client, port, true);

    datastore.invoke(new SerializableCallable<Object>() {
      @Override
      public Object call() {
        Region<CustId, Customer> pr = getGemfireCache().getRegion(CUSTOMER);
        pr.getAttributesMutator().setCacheLoader(new CacheLoader<CustId, Customer>() {
          @Override
          public void close() {}

          @Override
          public Customer load(LoaderHelper<CustId, Customer> helper) throws CacheLoaderException {
            throw new RuntimeException("Loader should not be called");
          }
        });
        pr.put(new CustId(10), new Customer("name10", "address10"));
        pr.invalidate(new CustId(10));
        return null;
      }
    });

    client.invoke(new SerializableCallable<Object>() {
      @Override
      public Object call() {
        TXManagerImpl mgr = getGemfireCache().getTxManager();
        // Region<Integer, String> r = getGemfireCache().getRegion(D_REFERENCE);
        Region<CustId, Customer> pr = getGemfireCache().getRegion(CUSTOMER);
        CustId key = new CustId(0);
        Customer val = new Customer("name0", "address0");
        pr.put(key, val);
        mgr.begin();
        Entry entry = pr.getEntry(key);
        assertNotNull(entry);
        assertEquals(key, entry.getKey());
        assertEquals(val, entry.getValue());
        Entry entry2 = pr.getEntry(new CustId(10));
        assertNotNull(entry2);
        assertEquals(new CustId(10), entry2.getKey());
        assertNull(entry2.getValue());
        assertNull(pr.getEntry(new CustId(100)));
        mgr.commit();
        return null;
      }
    });
  }
test has a client, two accessors and a datastore pool connects to two accessors. we then close
the server in first accessor and verify failover
geode-core/src/distributedTest/java/org/apache/geode/internal/cache/ClientServerTransactionDUnitTest.java