anchor.diff:  		    inet_db:ins_alt_ns(IP, Port);
   		_ -> ok
   	    end,
  +            %% dbg:tracer(),
  +            %% dbg:p(all, c),
  +            %% dbg:tpl(inet_res, query_nss_res, cx),
   	    [{nameserver,NsSpec},{res_lookup,Lookup}|Config]
       catch
   	SkipReason ->
  
positive.code:     end;
  tolower([]) ->
      [].
  
negative.code: 	_ ->
  	    ok
      end.
  
  %% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  %% Internal name server
  
  ns_internal(ServerSpec, Mref, Tag, S) ->
      receive
          {'DOWN',Mref,_,_,Reason} ->
              exit(Reason);
          Tag ->
              ok;
          {udp,S,IP,Port,Data} ->
              Req = ok(inet_dns:decode(Data)),
              Resp = ns_internal(ServerSpec, Req),
              RespData = inet_dns:encode(Resp),
              _ = ok(gen_udp:send(S, IP, Port, RespData)),
              _ = ok(inet:setopts(S, [{active,once}])),
              ns_internal(ServerSpec, Mref, Tag, S)
      end.
  
  ns_internal(#{rcode := Rcode}, Req) ->
      Hdr = inet_dns:msg(Req, header),
      Opcode = inet_dns:header(Hdr, opcode),
      Id = inet_dns:header(Hdr, id),
      Rd = inet_dns:header(Hdr, rd),
      %%
      Qdlist = inet_dns:msg(Req, qdlist),
      inet_dns:make_msg(
         [{header,
           inet_dns:make_header(
             [{id,Id},
              {qr,true},
              {opcode,Opcode},
              {aa,true},
              {tc,false},
              {rd,Rd},
              {ra,false},
              {rcode,Rcode}])},
           {qdlist,Qdlist}]).
  
  %% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  %% Behaviour modifying nameserver proxy
  