@After
  public void tearDown() throws Exception {
    if (cache != null) {
      cache.close();
    }
    if (system != null) {
      system.disconnect();
    }
    ClientHealthMonitor.shutdownInstance();
  }
Close the cache and disconnects from the distributed system
geode-core/src/integrationTest/java/org/apache/geode/internal/cache/tier/sockets/ClientHealthMonitorIntegrationTest.java