MoinQ:

DNS/キャッシュサーバ/BIND/9.4.0について、ここに記述してください。

BIND 9.4.0

        BIND 9.4.0 has a number of new features over 9.3,
        including:

        Implemented "additional section caching (or acache)", an
        internal cache framework for additional section content to
        improve response performance.  Several configuration options
        were provided to control the behavior.

確かに、 additional section の A を返してこない。

一方でこういう不良も: