mrtg.yeg01.ca.as4250.net has no NS records.
NS records for this zone are defined at as4250.net.
NS records for this zone are defined at as4250.net.
Question and response
Question
dig mrtg.yeg01.ca.as4250.net. NS
Answer
The response has no answer records.
Authority
as4250.net. 3601 SOA dns1.registrar-servers.com. hostmaster.registrar-servers.com. 1773395990 43200 3600 604800 3601
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0