smtp1.esp.vodafone.pt has no NS records.
NS records for this zone are defined at vodafone.pt.
NS records for this zone are defined at vodafone.pt.
Question and response
Question
dig smtp1.esp.vodafone.pt. NS
Answer
The response has no answer records.
Authority
vodafone.pt. 300 SOA ns-a1.vodafone.pt. dnsadmin.corp.vodafone.pt. 2026031201 10800 3600 1209600 300
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0