[dns-operations] does it matter when nameserver recs have non-matching PTRs ?

[Paul Vixie]

i like ptr's for nameservers, because it proves that the owner of the ip
address knows they're running a name server and are comfortable having
zones delegated to it.

otherwise, someone can list a web server name as an NS RR for some
low-value names, spam the hell out of those names, and then up ddos'ing
the web server with DNS packets.