anchor.diff:      case Msg of
           {handover, success, _NewLease} ->
               % disable new lease
  -            log:log("prepare_send_delta2 ~p~n", [Msg]),
  +            %log:log("prepare_send_delta2 ~p~n", [Msg]),
               %State1 = locally_disable_lease(State, NewLease),
               {ok, State, SlideOp};
           {split, fail, _Lease} ->
  
positive.code:         -> {ok, dht_node_state:state(), slide_op:slide_op()}.
  prepare_send_delta1(State, OldSlideOp, ReplyPid) ->
      % start to split own range
      log:log("prepare_send_delta1 ~p~n", [slide_op:get_type(OldSlideOp)]),
      case find_lease(State, OldSlideOp, active) of
          {ok, Lease} ->
              Id = l_on_cseq:id(l_on_cseq:get_range(Lease)),
  
negative.code: finish_delta_ack1(State, OldSlideOp, ReplyPid) ->
      % handover lease to succ
      comm:send_local(ReplyPid, {continue}),
      %log:log("finish_delta_ack1~n", []),
      {ok, State, OldSlideOp}.
  
  %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  