Re: [webmin-l] Is postfix greylisting working correctly???

[Jamie C. <jca...@we...>]

On 11/Sep/2011 15:11 Steve Holdoway <st...@gr...> wrote ..
> I've just been doing dome testing on mail forwarding for a debian lenny
> server running virtualmin 3.87.gpl / webmin 1.560.
> 
> My mail server was giving up, rather than retry on a greylisted mail
> request. Further investigation showed the difference between the
> virtualmin setup and my own ( sendmail / milter-greylist ) the the
> following:
> 
> Virtualmin:
> NOQUEUE: reject: RCPT from palma.ourhostingservers.com[208.101.19.98]:
> 450 4.2.0 <in...@ex...>: Recipient address rejected: Greylisted,
> see http://postgrey.schweikert.ch/help/example.com.html;
> from=<no...@pa...> to=<in...@ex...>
> proto=ESMTP helo=<palma.ourhostingservers.com
> 
> Sendmail:
> Milter: to=<st...@ex...>, reject=451 4.7.1 Greylisting in action
> 
> Checking the response codes...
> 450 Requested mail action not taken: mailbox unavailable 
> 451 Requested action aborted: local error in processing
> 
> Surely your greylisting should be returning a 451 code??? I know my mail
> server gives up when it received a 450, but that could well be my
> problm.

Both 450 and 451 should be acceptable indications that the message should
be re-tried. According to the SMTP specification at http://www.rfc-editor.org/rfc/rfc2821.txt , 
all 4xx codes indicate a temporary or transient problem ..

 - Jamie