joinUsers(channelName, someUsers);
checkUsersJoined(channelName, someUsers);
holdChannelServerMethodToNode(serverNode, "close");
leaveAll(channelName);
waitForHeldChannelServerMethodToNode(serverNode);
coordinatorNode.shutdown(false);
Thread.sleep(2000);
checkUsersJoined(channelName, noUsers);
for (DummyClient client : group.getClients()) {
client.assertLeftChannel(channelName);
}