anchor.diff:  -behaviour(gen_server).
   
   %% API
  --export([start_link/0]).
  +-export([start_link/0,
  +         possible_change/0]).
   
   %% Support API
   -export([ensembles/0,
  
positive.code:                             [Ensemble | Acc]
                      end
                  end, [], ensembles()).
                      
  ensembles() ->
      {ok, Ring} = riak_core_ring_manager:get_my_ring(),
      required_ensembles(Ring).
  
negative.code: start_link() ->
      gen_server:start_link({local, ?MODULE}, ?MODULE, [], []).
  
  possible_change() ->
      ?MODULE ! reset_ring_id.
  
  local_ensembles() ->
      Node = node(),
  