shield01.bbo.berlin has no CNAME records.
Question and response
Question
dig shield01.bbo.berlin. NS
Answer
The response has no answer records.
Authority
bbo.berlin. 212 SOA ns1.dns-hotel.net. hm.bb-one.net. 2026021601 10800 3600 604800 38400
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0