On Tue, Sep 20, 2016 at 05:30:27PM -0400, Alex Hall wrote:
> Bottom line: on one server, everything was great. On my company's virtual
> server, with the same configuration, packages, and settings, mail sent out
> is silently discarded by Gmail when delivered to anyone on the company's
> domain. I must be missing required envelope details somewhere, but I don't
> know where. I'm hoping someone can suggest where I can look, and what I can
> try, to fix this. Please let me know what additional information is
> required to troubleshoot this problem. Thank you in advance.
Have you looked at the postfix SMTP logs? Generally, if a mail server
doesn't like a mail, it will reject it (e.g. with 550) rather than
accept it and silently discard it.
Whenever postfix sends a message, there should be a line in its logs
that looks something like this:
> Sep 20 17:34:30 mailserver_hostname postfix/smtp: D2A5184FE1:
> relay=gmr-smtp-in.l.google.com[2607:f8b0:4001:c1e::e]:25, delay=0.88,
> delays=0.2/0.03/0.41/0.24, dsn=2.0.0, status=sent (250 2.0.0 OK 1474407270
> f13 3si2432297ita.1 - gsmtp)
Note in particular the "status=sent (250 ...)" part. 250 means the
server accepted my message. A status like 550 means permanent rejection,
450 means temporary rejection, etc.
Compare the logs from when it works and when it doesn't. See if there's
any differences in the status responses.