smtp.exclaimer.com has no NS records.
NS records for this zone are defined at exclaimer.com.
NS records for this zone are defined at exclaimer.com.
Question and response
Question
dig smtp.exclaimer.com. NS
Answer
The response has no answer records.
Authority
exclaimer.com. 1800 SOA eva.ns.cloudflare.com. dns.cloudflare.com. 2397691073 10000 2400 604800 1800
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0