pns4.linuxpower.at has no CNAME records.
Question and response
Question
dig pns4.linuxpower.at. NS
Answer
The response has no answer records.
Authority
linuxpower.at. 2995 SOA pns1.linuxpower.at. chris.linuxpower.at. 2026021101 7200 1800 1209600 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0