smtp4.citra.net.id has no MX records.
Question and response
Question
dig smtp4.citra.net.id. MX
Answer
The response has no answer records.
Authority
citra.net.id. 60 SOA tugu.as23951.com. postmaster.citra.net.id. 2026021401 3600 600 1209600 3600
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0