On Fri, Apr 18, 2014 at 04:21:43PM +0000, Robert Becker wrote:
> I'm running Postfix as my front-end MTA with Exchange 2010 behind it and
> I'm trying to determine the best way to verify recipients on inbound mail.
> I like the simplicity of using the built in verify functionality in Postfix,
> but when I put warn_if_reject reject_unverified_recipients into my
> smtpd_recipient_restrictions, I get a verify database that contains valid
> accounts and a bunch of invalid ones and nothing warns on rejects in the
> maillog. I've configured Exchange to reject senders not in the address
> book, but it looks as though Postfix is not getting a good verification.
> I've telnetted from the Postfix server to Exchange and confirmed that I
> get a reject when I attempt to specify a RCPT TO that is not a valid
> address. How do I go about troubleshooting what server Postfix is
> verifying against. The Exchange servers are the next hop as specified in
> the transport map. I've reviewed the ADDRESS_VERIFICATION_README, but am
> not finding what I need to troubleshoot this issue there. What else do
The answer is in your mail logs. Successful verification probes
are logged as "status=deliverable", while failed probes are logged
as "status=undeliverable". The log message will show why.
You can also test with "sendmail -f your-address -bv target-address"
and you'll receive a DSN messages which details the nexthop relay's
reply to the probe message.
--
Viktor.
