anchor.diff:  
               case rebalance_1(State, Nodes) of
                   {ok, RetRebalance} ->
  -                    case leo_redundant_manager_api:get_members() of
  -                        {ok, Members_2} ->
  +                    case get_members_of_all_versions() of
  +                        {ok, {MembersCur, MembersPrev}} ->
                               {ok, SystemConf} = leo_manager_mnesia:get_system_config(),
  -                            case rebalance_3(Nodes, #rebalance_proc_info{members_cur = Members_2,
  -                                                                         system_conf = SystemConf}) of
  +                            case rebalance_3(Nodes, #rebalance_proc_info{members_cur  = MembersCur,
  +                                                                         members_prev = MembersPrev,
  +                                                                         system_conf  = SystemConf}) of
                                   ok ->
                                       _ = distribute_members([N || {_, N} <- Nodes]),
                                       rebalance_5(RetRebalance, []);
  
positive.code: -spec(rebalance() ->
               ok | {error, any()}).
  rebalance() ->
      case leo_redundant_manager_api:get_members() of
          {ok, Members_1} ->
              {State, Nodes} =
                  lists:foldl(
  
negative.code:                                     ?error("rebalance/0", "cause:~p", [Cause]),
                                      {error, Cause}
                              end;
                          Error ->
                              Error
                      end;
  