David Rankin wrote:

Listmates, Sandy in particular

After adding:

smtpd_client_restrictions = check_client_access cidr:/etc/postfix/client_check.cidr, reject_rbl_client relays.ordb.org, reject_rbl_client sbl-xbl.spamhaus.org, reject_rbl_client list.dsbl.org, reject_unknown_client

I can't send mail from Postfix at home to postfix at work. The problem is the "reject_unknown_client" restriction which causes the server at work to reject the message. If I remove the restriction it works fine. The error is:

Jul 26 23:14:10 bonza postfix/smtpd[22176]: connect from unknown[66.76.63.120] Jul 26 23:14:10 bonza postfix/smtpd[22176]: NOQUEUE: reject: RCPT from unknown[66.76.63.120]: 550 Client host rejected: cannot find your hostname, [66.76.63.120]; from= to= proto=ESMTP helo= Jul 26 23:14:11 bonza postfix/smtpd[22176]: disconnect from unknown[66.76.63.120]

(Note -- I inserted the #### stuff in this message to prevent the address from being skimmed from list archives)

What I don't understand is why I get the log entry of "RCPT from unknown[66.76.63.120]"? 66.76.63.120 is certainly known. It's 3111skyline.com. Why is the "unknown" happening. Any ideas??? Is it a problem with my home mail setup not sending a hostname?? (not likely, helo got it) is it a domain mx record problem? Is it a timeout problem on the reverse lookup?

# dig -x 66.76.63.120 +short cdm-66-76-63-120.nacd.static.cox-internet.com. # dig cdm-66-76-63-120.nacd.static.cox-internet.com +short # Reverse DNS of your ip exists and points zu cdm-66-76-63-120.nacd.static.cox-internet.com, unfortunately a host named cdm-66-76-63-120.nacd.static.cox-internet.com does not exist in forward dns. That is the reason why Postfix regards your host as "unknown". If you look again at my mail about your config, you will notice that I commented the restriction "reject_unknown_client" (and of course bl.spamcop.net), because they reject too much real mail. Sandy -- List replies only please! Please address PMs to: news-reply2 (@) japantest (.) homelinux (.) com -- Check the headers for your unsubscription address For additional commands send e-mail to suse-linux-e-help@suse.com Also check the archives at http://lists.suse.com Please read the FAQs: suse-linux-e-faq@suse.com