ntp.grumpyminx.com has no MX records.
Question and response
Question
dig ntp.grumpyminx.com. MX
Answer
The response has no answer records.
Authority
grumpyminx.com. 600 SOA ns1.grumpyminx.com. pete.318.org.uk. 2026030500 86400 7200 3600000 172800
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0