On 6/7/2013 8:06 AM, Nikolas Kallis wrote: > Hello, > > > > I just got an unsolicited e-mail from the domain 'bbbmail.com', which is > hosted at '46.235.78.1'. > > '46.235.78.1' does not resolve to a host name, therefore 'bbbmail.com' > is not a FQDN.
$ host 46.235.78.1 Host 1.78.235.46.in-addr.arpa. not found: 3(NXDOMAIN) reject_unknown_reverse_client_hostname triggers on NXDOMAIN. This has nothing to do with HELO, but a reverse lookup of the client IP address. > I have 'reject_non_fqdn_helo_hostname' enabled; how did this unsolicited > e-mail get through? One, see above. Two, because reject_non_fqdn_helo_hostname does not trigger on NXDOMAIN. Using reject_unknown_reverse_client_hostname would have rejected this spam connection with a 450. See: http://www.postfix.org/postconf.5.html#reject_unknown_reverse_client_hostname -- Stan
