@After
  public void tearDown() throws Exception {
    for (VM vm : toArray(managerVM, memberVM1, memberVM2, memberVM3)) {
      vm.invoke(() -> {
        if (cache != null) {
          cache.close();
        }
        cache = null;
        distributedMember = null;
        managementService = null;
        distributedSystemMXBean = null;
      });
    }
  }
Distributed tests for {@link DistributedSystemMXBean} notifications.

<pre>
a) Concurrently modify proxy list by removing member and accessing the distributed system MBean
b) Aggregate Operations like shutDownAll
c) Member level operations like fetchJVMMetrics()
d ) Statistics
</pre>
geode-core/src/distributedTest/java/org/apache/geode/management/DistributedSystemMXBeanDistributedTest.java