dns21.telus.ca has no CNAME records.
Question and response
Question
dig dns21.telus.ca. NS
Answer
The response has no answer records.
Authority
telus.ca. 825 SOA dns48.telus.com. dnsadmin2.telus.com. 2019277037 900 90 3600000 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0