mxout01.uptime.de has no NS records.
NS records for this zone are defined at uptime.de.
NS records for this zone are defined at uptime.de.
Question and response
Question
dig mxout01.uptime.de. NS
Answer
The response has no answer records.
Authority
uptime.de. 6000 SOA ns01.uptime.de. hostmaster.uptime.de. 2026012700 10800 3600 1814400 21600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0