On 14/05/2024 08.10, Josef Karliak via knot-dns-users wrote:
   ISC bind is strict about CNAME of NS server:
 skipping nameserver 'aa.bb.cz' *because it is a CNAME*, while
 resolving '9.4/4.3.2.1.in-addr.arpa/PTR'.
   How about Knot resolver ?
 
Hello.  I believe there is neither effort to disallow them nor to make
them work.  Off the top of my head I'm not sure how it will be in
practice; you could just try.  Either way, please don't use them.
(I replied to the correct mailing-list.)
--Vladimir