ns7.oleane.net has no NS records.
NS records for this zone are defined at oleane.net.
NS records for this zone are defined at oleane.net.
Question and response
Question
dig ns7.oleane.net. NS
Answer
The response has no answer records.
Authority
oleane.net. 600 SOA ns6.oleane.net. admp-ess-imap.oleane.net. 2015066273 14400 2000 2500000 600
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0