On 05/08/2013 07:31 PM, Mike Marcott wrote:
> The Problem: external senders are getting a delay DSN on their end. Mail usually comes through to us though, but can take up to 24 hours!
>
> What I've found so far: looks like exim is blocking the emails for certain senders. Log files from /var/log/exim/reject.log are littered with host lookup errors as such
> (names & ip's changed to protect the innocent)
>
> 2013-02-17 08:25:49 H=(owa.mycustomer.com) [XXX.XXX.XXX.XXX] F=<them@???> temporarily rejected RCPT <me@???>: host lookup deferred for reverse lookup check
> 2013-02-17 08:26:50 H=(owa.mycustomer.com) [XXX.XXX.XXX.XXX] F=<them@???> temporarily rejected RCPT <me@???>: host lookup deferred for reverse lookup check
> 2013-02-17 08:27:51 H=(owa.mycustomer.com) [XXX.XXX.XXX.XXX] F=<them@???> temporarily rejected RCPT <me@???>: host lookup deferred for reverse lookup check
> 2013-02-17 08:28:52 H=(owa.mycustomer.com) [XXX.XXX.XXX.XXX] F=<them@???> temporarily rejected RCPT <me@???>: host lookup deferred for reverse lookup check
> 2013-02-17 08:29:53 H=(owa.mycustomer.com) [XXX.XXX.XXX.XXX] F=<them@???> temporarily rejected RCPT <me@???>: host lookup deferred for reverse lookup check
> 2013-02-17 08:30:54 H=(owa.mycustomer.com) [XXX.XXX.XXX.XXX] F=<them@???> temporarily rejected RCPT <me@???>: host lookup deferred for reverse lookup check
>
> (Why every minute? even after the message is delivered?)
Not enough info (and your protecting the "innocent" does not help here).
Probably they (the external sender) are retrying every minute.
>
> I've done a reverse dns lookup on the owa.mycustomer.com and found it exists.
I bet it's flakey.
> Any help would be appreciated. Thank you!
Somewhere in your rcpt acl there's a verify= reverse_host_lookup line. Find the right one, and wrap it
so that it doesn't get called for this host.
Or fix your (or their) dns.
--
Cheers,
Jeremy