ns.zxcs.de has no MX records.
Question and response
Question
dig ns.zxcs.de. MX
Answer
The response has no answer records.
Authority
zxcs.de. 3600 SOA nsauth.zxcs.nl. hostmaster.zxcs.nl. 2025061701 10800 3600 1209600 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0