Q: Configuration Change - "Client host rejected: cannot find your hostname"
a potential customer has tried to e-mail us, and has been complaining that their e-mail is "bounced"..
Here is a snippet of the logs showing the problem
Aug 24 03:03:57 mail postfix/smtpd: NOQUEUE: reject: RCPT from unknown[188.8.131.52]: 450 4.7.1 Client host rejected: cannot find your
hostname, [184.108.40.206]; from=<email@example.com> to=<firstname.lastname@example.org> proto=ESMTP helo=<milan.hostgo.com>
milan.hostgo.com has not been obfuscated, that is what's being sent as the helo
I have the following enabled:
Global Settings > MTA > Protocol Checks
Hostname in greeting violateds RFC (reject_invalid_hostname)
Client must greet with a fully qualified hostname (reject non_fqdn hostname)
(this one would be the one to uncheck to allow mail in this situation - correct?)
Sender address must be fully qualified (reject_non-fqdn_sender)
Global Settings > MTA > DNS Checks
Client's IP Address (reject_unknown_client)
Hostname in greeting (reject unknown hostname)
Sender's Domain (reject_unknown_sender_domain)
Is it possible to allow mail from this one mail server (milan.hostgo.com) or (hostgo.com) to bypass the protocol and dns checks?
If so, how would I go about implementing this?
Thank you very much
Release 7.1.1_GA_3196.RHEL5_64_20110527011124 CentOS5_64 FOSS edition.
Release 7.1.1_GA_3196.RHEL5_64_20110527011124 CentOS5_64 FOSS edition