code: @Override
    protected void channelRead0(final ChannelHandlerContext ctx, final ByteBuf msg) throws Exception {
      ResponseStatus status = MessageUtil.getResponseStatus(msg);
      if (status.isSuccess()) {
        negotiate(ctx);
      } else {
        originalPromise().setFailure(new IllegalStateException("Could not configure DCP Controls: " + status));
      }
    }
docs: Since only one feature per req/res can be negotiated, repeat the process once a response comes
  back until the iterator is complete or a non-success response status is received.