> I have an Exim instance running on Debian Jessie. For each mail that is > received by Exim I would like to check if the reverse DNS for the sender > domain matches the connecting IP and if not reject the mail. > > Consider the following scenarios. > * A spammer sends an email from the IP 94.123.123.123 with > [email protected] in the "From" field but the domain > spammerwebsite.com doesn't resolve to 94.123.123.123. I want this to be > blocked.
This will bounce a great deal of perfectly legitimate email from a lot of domains, even with quite loose matching. > P.S. > * Where can I find the correct documentation? http://www.exim.org/, see the Documentation link. Yes, you will have to read much of the large manual. > * Why can't the configuration start from an empty file? Various people will have various answers, but my answer is that it doesn't because Exim is a mailer construction kit. It is not doing anything when you start it with an empty configuration file for the same reason that a construction firm is not going to do anything if you say 'build me something' without specifying what you want built. - cks -- ## List details at https://lists.exim.org/mailman/listinfo/exim-users ## Exim details at http://www.exim.org/ ## Please use the Wiki with this list - http://wiki.exim.org/
