_nb1.drei.host has no CNAME records.
Question and response
Question
dig _nb1.drei.host. NS
Answer
The response has no answer records.
Authority
drei.host. 2982 SOA adns1.drei.com. at\.dns.drei.com. 2026030201 14400 3600 604800 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0