@Override
  public final void preTearDown() throws Exception {
    // close the clients first
    closeCache();

    // then close the servers
    server1.invoke(HAStartupAndFailoverDUnitTest::closeCache);
    server2.invoke(HAStartupAndFailoverDUnitTest::closeCache);
    server3.invoke(HAStartupAndFailoverDUnitTest::closeCache);
    CacheServerTestUtil.resetDisableShufflingOfEndpointsFlag();
  }
Tests failover initialization by cache operation Threads on secondary
geode-core/src/distributedTest/java/org/apache/geode/internal/cache/tier/sockets/HAStartupAndFailoverDUnitTest.java