greetings all day long I see tons of reject warnings from different ips sample reject_warning: RCPT from unknown[65.60.20.157]: 450 Client host rejected: cannot find your hostname, [65.60.20.157];
when I do an nslookup or host that IP it returns a 157.20.60.65.in-addr.arpa domain name pointer sh4.amazingfireman.info but dig returns nothing so postfix returns a reject warning. Much of this mail is unwanted , i want to block the majority of these however I do not want to block users that use a colocation site or legit users; example; i know these people are legit but have no control over their mailserver reject_warning: RCPT from unknown[209.131.70.106]: 450 Client host rejected: cannot find your hostname, [209.131.70.106]; from=<u...@dhuy.com> Non-authoritative answer: 106.70.131.209.in-addr.arpa name = ip70-106-tcpbbs.net. dig shows nothing for that ip but they do have an mx record under their domain name dhuy.com ;; ANSWER SECTION: dhuy.com. 1595 IN MX 10 mail.dhuy.com. Name: mail.dhuy.com Address: 209.131.70.106 nc1-100:~ drfoo$ host 209.131.70.106 106.70.131.209.in-addr.arpa domain name pointer ip70-106-tcpbbs.net it goes in a circle. So in hopes that i can allow them to pass i have added the IP to my smtpd_client_restrictions = permit_mynetworks check_client_access hash:/etc/postfix/access is that the right approach ? insight and flames welcome -j
