I’ve been searching and reading through numerous posts, but can’t seem to find a resolution to my email issue.
I’m seeing the following in my logs, every few minutes;
Apr 10 23:53:50 toronto01 postfix/smtpd: warning: hostname toronto01.kasnetwork.com does not resolve to address 126.96.36.199 Apr 10 23:53:50 toronto01 postfix/smtpd: connect from unknown[188.8.131.52] Apr 10 23:53:50 toronto01 postfix/smtpd: disconnect from unknown[184.108.40.206]
I have reverse pointers setup and the hostname does resolve at mxtoolbox --> https://mxtoolbox.com/SuperTool.aspx?action=ptr%3A220.127.116.11&run=toolpage
I just can’t seem to figure out why this error occurs as the logs offer no real explanation. No rejected messages, or SASL login failed, etc., such as this entry;
Apr 10 23:59:42 toronto01 postfix/smtpd: warning: hostname 80-69-247-10.pasargadnet.ir does not resolve to address 18.104.22.168 Apr 10 23:59:42 toronto01 postfix/smtpd: connect from unknown[22.214.171.124] Apr 10 23:59:45 toronto01 postfix/smtpd: warning: unknown[126.96.36.199]: SASL LOGIN authentication failed: UGFzc3dvcmQ6 Apr 10 23:59:45 toronto01 postfix/smtpd: disconnect from unknown[188.8.131.52]
I don’t know where this “connection” is coming from. It appears as if the server is connecting to itself, but for what reason and why it doesn’t resolve I just can’t understand.
Any pointers would be greatly appreciated!
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