@SuppressWarnings("unchecked")
  public String[] shutDownAllMembers() throws Exception {
    try {
      DistributionManager dm = cache.getDistributionManager();
      Set<InternalDistributedMember> members = ShutdownAllRequest.send(dm, 0);
      String[] shutDownMembers = new String[members.size()];
      int j = 0;
      for (InternalDistributedMember member : members) {
        shutDownMembers[j] = member.getId();
        j++;
      }
      return shutDownMembers;
    } catch (Exception e) {
      throw new Exception(e.getLocalizedMessage());
    }
  }
@return the set of members successfully shutdown
geode-core/src/main/java/org/apache/geode/management/internal/beans/DistributedSystemBridge.java