mx2.feishu.cn has no NS records.
NS records for this zone are defined at feishu.cn.
NS records for this zone are defined at feishu.cn.
Question and response
Question
dig mx2.feishu.cn. NS
Answer
The response has no answer records.
Authority
feishu.cn. 600 SOA vip3.alidns.com. hostmaster.hichina.com. 2025121112 3600 1200 86400 600
Additional
. 0 OPT ; payload 1280, xrcode 0, version 0, flags 0