I need to learn more about BIND DNS server to pass my job interview next Monday

[Stephane Bortzmeyer]

On Sun, Sep 14, 2025 at 10:42:45AM +0200,
 Benny Pedersen via bind-users <bind-users at lists.isc.org> wrote 
 a message of 23 lines which said:

> mx.junc.eu (amavis); dkim=neutral reason="invalid (public key: not
> available)" header.d=i header.b="YUOrfkQZ"; dkim=fail (2048-bit key)
> reason="fail (message has been altered)" header.d=junc.eu
> header.b="WqO6E6ri"
> 
> is isc.org miss dkim public key on dns ?

Indeed, default._domainkey.junc.eu does not exist so it is not just at ISC.

(Also, the number of large RSA signatures forced me to switch to TCP.)