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Author: Pete

docs/hardening/postfix-ldap/README.md

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+If mails get transparently forwarded to another mailserver, a mechanism to block
+mail for invalid recipients makes sense, and drastically increaes the well-known
+backscatter problem.
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+LDAP queries are used to check for valid recipients, and forwards the mail, if
+an entry for the user is found.
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+For this to work, on Debian/GNU Linux, you also have to install postfix-ldap by
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+apt install postfix-ldap
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+Further information can be found @ https://blog.nwsec.de/wordpress/?p=1031
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