anchor.diff:  
   % API
   -export([ensure_config_pushed/0,
  -         ensure_config_seen_by_nodes/0, ensure_config_seen_by_nodes/1,
  +         ensure_config_seen_by_nodes/0,
  +         ensure_config_seen_by_nodes/1, ensure_config_seen_by_nodes/2,
            pull_and_push/1, pull_from_one_node_directly/1]).
   
   -export([get_remote/2, pull_remotes/1]).
  
positive.code:     ensure_config_seen_by_nodes(ns_node_disco:nodes_actual_other()).
  
  ensure_config_seen_by_nodes(Nodes) ->
      ns_config:sync_announcements(),
      synchronize_remote(Nodes).
  
  pull_and_push([]) -> ok;
  pull_and_push(Nodes) ->
  
negative.code: synchronize_local() ->
      gen_server:call(?MODULE, synchronize, ?SYNCHRONIZE_TIMEOUT).
  
  synchronize_remote(Nodes, Timeout) ->
      ok = synchronize_local(),
      {_Replies, BadNodes} =
          misc:multi_call(Nodes, ?MODULE,
                          synchronize_everything, Timeout,
                          fun (R) ->
                                  R =:= ok
                          end),
  