Re: [SSHGuard-users] sshguard-users Digest, Vol 94, Issue 4

[Christos C. <ch...@cr...>]

> 
> Those dynamic IP addresses can be filtered in postfix. I set this up so
> long ago that I don't recall the details, but this is the relevant line
> in postfix main.cf:
> check_reverse_client_hostname_access pcre:/etc/postfix/fqrdns.pcre
> 
> Google digs up:
> http://postfix.1071664.n5.nabble.com/New-approach-with-fqrdns-pcre-file-td90262.html
> https://github.com/stevejenkins/hardwarefreak.com-fqrdns.pcre
> 
> If the original poster goes this route, I would suggest consulting the
> postfix mailing list.
> 

Just make sure that the check_reverse_client_hostname_access or check_client_access (for newer versions of Postfix) is after 
permit_mynetworks and permit_sasl_authenticated else the authenticated clients from dynamic IPs will not be able to send e-mail.