I have email not being delivered from specific domains. I have turned off anti-virus / spam filtering for the receiving email. Incoming email shows in log as follows: May 18 10:27:01 renmus postfix/smtpd[9031]: NOQUEUE: filter: RCPT from unknown[##.##.##.###]: <JAlman@#########.com>: Sender address triggers FILTER amavis:[127.0.0.1]:10024; from=<JAlman@#########.com> to=<john.bresnahan@#########.com> proto=ESMTP helo=<out.exch080.#########.net> May 18 10:27:01 renmus postfix/smtpd[9031]: NOQUEUE: reject: RCPT from unknown[##.##.##.###]: 450 4.7.1 <out.exch080.#########.net>: Helo command rejected: Host not found; from=<JAlman@#########.com> to=<john.bresnahan@#########.com> proto=ESMTP helo=<out.exch080.#########.net> Is there a way to correct this?; reverse server lookup appears to be preventing delivery. How can I allow for this domain to pass? Thank you in advance for your assistance.
it can't find the host "out.exch080.#####.net" right? is it something like your internal exchange-server with some domain not real for the outside world? Add it to the /etc/hosts file or change the authentication, use port 587 tls and auth before sending. or delete the reject_invalid_host ( something like that, off the head ) value for senders, which might be bad.
Thanks for the help - you got me on the right path. Removed the following smtpd_helo_restrictions: reject_invalid_hostname, reject_non_fqdn_hostname, reject_invalid_helo_hostname, reject_unknown_helo_hostname. I don't know if this is good practice as their hostname does not resolve to an IP address. I hope that I am not introducing trouble on my end to accommodate someone else's issue. If anyone has a comment on this change, please comment. Thanks again.
