anchor.diff:      {stop, normal, ok, State};
   
   handle_call(force_sync,_From, State) ->
  -    %% @TODO
  -    %% ok = exec(),
  +    ok = sync_1(),
       {reply, ok, State}.
   
   
  
positive.code:              ok | {error, any()}).
  exec([]) ->
      ok;
  exec([#cluster_manager{node = _Node,
                         cluster_id = _ClusterId}|Rest]) ->    
      exec(Rest).
  
negative.code: 
  -include("leo_manager.hrl").
  -include_lib("leo_redundant_manager/include/leo_redundant_manager.hrl").
  -include_lib("leo_s3_libs/include/leo_s3_auth.hrl").
  -include_lib("leo_s3_libs/include/leo_s3_bucket.hrl").
  -include_lib("leo_s3_libs/include/leo_s3_libs.hrl").
  -include_lib("leo_s3_libs/include/leo_s3_user.hrl").
  -include_lib("eunit/include/eunit.hrl").
  
  %% API
  