smtpgw2.turknet.net.tr has no MX records.
Question and response
Question
dig smtpgw2.turknet.net.tr. MX
Answer
The response has no answer records.
Authority
turknet.net.tr. 3600 SOA ns.turk.net. dnsadmin.turk.net. 2026030200 10800 3600 604800 86400
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0