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Deny smtp connection from unknown and unverified hosts with hosts.deny

rated 0 times [ 0] [ 0] / answers: 1 / hits: 861 / 2 Years ago, thu, september 29, 2022, 4:25:43

I need to reject all smtp connections whose host name is unknown or does not match its address. Have tried setting in hosts.deny:

smtpd: UNKNOWN

smtpd: PARANOID

but Postfix logs show that they are still getting through to the mail deamon.

postfix/smtpd[3426]: warning: hostname server1.reselect.org does not resolve to address 89.33.194.240

postfix/smtpd[3426]: connect from unknown[89.33.194.240]

postfix/smtpd[3426]: NOQUEUE: reject: CONNECT from unknown[89.33.194.240]: 450 4.7.25 Client host rejected: cannot find your hostname, [89.33.194.240]; proto=SMTP

...

postfix/smtpd[3997]: connect from unknown[193.56.29.102]

postfix/smtpd[3997]: NOQUEUE: reject: CONNECT from unknown[193.56.29.102]: 450 4.7.25 Client host rejected: cannot find your hostname, [193.56.29.102]; proto=SMTP

Why does it not work?