Re: Spam Filters Not Catching Repeating Offenders?
- LuKreme wrote:
>That's irrelevant. The client doesn't claim to be unknown,
> On 30-Mar-2009, at 14:40, Noel Jones wrote:
>> LuKreme wrote:
>>> On 30-Mar-2009, at 13:20, Carlos Williams wrote:
>>>> Received: from 126.96.36.199.man-static.vsnl.net.in (unknown
>>>> by mail.ideorlando.org (Postfix) with ESMTP id 910AA1FA4D9E
>>>> for <everyone@...>; Mon, 30 Mar 2009 10:32:52 -0400 (EDT)
>>> There are so many spam warnings in that header...
>>> /^unknown$/ REJECT helo No unknown hostnames
>>> in your helo checks is a fantastic idea.
>> "unknown" isn't the helo, it's an unknown client. This client could
>> be rejected with reject_unknown_client_hostname, but that rejects too
>> much legit mail for most sites.
> It's also not a FQDN (or at least not a valid one).
it's labeled that way by postfix because (in this case)
there's no A record for the rDNS hostname.
Using an access table to reject anything labeled "unknown" is
unwise; you can't distinguish temporary errors and may reject
clients you would normally accept.
If you want to reject unknown clients, use
reject_unknown_client_hostname, which handles temporary errors
gracefully. Note this restriction is considered very strict
and is likely to reject legit mail.
-- Noel Jones