Client host rejected: cannot find your reverse hostname
Suddenly I can send any mail anymore. When I look in the logfile I see my mails being rejected with this error message “Client host rejected: cannot find your reverse hostname”. As far as I can’t remember I didn’t change a thing on the settings in the period when the change happened.
It is an Ubuntu site with Postfix. All mail commands are sent from PHP.
What could this be?
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