mx02.dsl4u.ca has no NS records.
NS records for this zone are defined at dsl4u.ca.
NS records for this zone are defined at dsl4u.ca.
Question and response
Question
dig mx02.dsl4u.ca. NS
Answer
The response has no answer records.
Authority
dsl4u.ca. 14400 SOA auth01.dns.acceleratedconnections.com. hostmaster.dsl4u.ca. 2025072300 14400 3600 1209600 86400
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0