Hi, I'm using zimbra with Postfix as MTA.
I got the following error message which indicate mail rejection based on hostname not find. Aug 26 04:05:49 courriel postfix/smtpd[17755]: NOQUEUE: reject: RCPT from unknown[67.210.171.12]: 450 4.7.1 Client host rejected: cannot find your hostname, [67.210.171.12]; from=<communi...@fcm.ca> to=<x...@domain.name.tld> proto=ESMTP helo=<smtp.fcm.ca> However, the DNS config of the sender's mta looks good. Here are the reverse resolution and the forward resolution: bd...@bdube-laptop:~$ host 67.210.171.12 12.171.210.67.in-addr.arpa domain name pointer smtp.fcm.ca. bd...@bdube-laptop:~$ host smtp.fcm.ca smtp.fcm.ca has address 67.210.171.12 And for the MX field for this domain, I got: bd...@bdube-laptop:~$ dig fcm.ca MX ; <<>> DiG 9.7.0-P1 <<>> fcm.ca MX ;; global options: +cmd ;; Got answer: ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 21616 ;; flags: qr rd ra; QUERY: 1, ANSWER: 3, AUTHORITY: 0, ADDITIONAL: 0 ;; QUESTION SECTION: ;fcm.ca. IN MX ;; ANSWER SECTION: fcm.ca. 900 IN MX 10 smtp.fcm.ca. fcm.ca. 900 IN MX 40 globalb.mxsave.com. fcm.ca. 900 IN MX 30 globala.mxsave.com. ;; Query time: 169 msec ;; SERVER: 24.200.241.37#53(24.200.241.37) ;; WHEN: Fri Aug 27 00:12:52 2010 ;; MSG SIZE rcvd: 103 Then, what are the other possible causes to have this mail rejected which are not tested by the commands I have done. Thanks for your help. Benoît
