anchor.diff:      lager:info("Node ~s left cluster", [NodeName]),
       {atomic, ok} = mnesia:del_table_copy(schema, NodeName).
   
  -have_disc_copy(Table) ->
  -    lists:member(node(), mnesia:table_info(Table, disc_copies)).
  -
   % end of file
  
positive.code:                     [ {atomic, ok} = mnesia:add_table_copy(T, node(), disc_copies)
                          || T <- mnesia:system_info(tables)--[schema]],
                      ok = mnesia:wait_for_tables(mnesia:system_info(local_tables), 10000),
                      application:start(lorawan_server);
                  {error, Reason} ->
                      lager:error("Cluster copy schema: ~p", [Reason]),
  
negative.code: join_cluster(NodeName) ->
      lager:info("Joining cluster ~s", [NodeName]),
  
      case {node(), net_adm:ping(NodeName)} of
          {NodeName, _} ->
              lager:error("Cluster: can't join myself: ~s", [NodeName]),
              {error, {cant_join_self, NodeName}};
  