Slightly OT: Greylisting success or failure stories?

[Thomas Cameron]

----- Original Message ----- 
From: "David Cary Hart" <Fedora at TQMcube.com>
To: "For users of Fedora Core releases" <fedora-list at redhat.com>
Sent: Thursday, February 03, 2005 8:59 PM
Subject: Re: Slightly OT: Greylisting success or failure stories?


> On Thu, 2005-02-03 at 20:34 -0600, Thomas Cameron wrote:
>> I have been using milter-greylist with Sendmail and I am *incredibly*
>> impressed.  Between SpamAssassin, spamass-milter, DCC, Pyzor, Razor, 
>> ClamAV,
>> clamav-milter, and milter-greylist, I literally receive no spam in my 
>> Inbox.
>> None.
>>
> I really dislike adding all that stuff.

I'm not arguing the point, but am really curious...  Why do you dislike it? 
Past initial setup there is zero administration.

> With NONE of the above, using three RBLs and our internal rlbdnsd we
> receive less than one spam per user per week. It's cleaner, faster, far
> more efficient and requires absolutely no maintenance.

I use (actually SA uses) RBLs as well.  And it takes zero maintenance.

> I should add that a great deal of spam is blocked with HELO checks. The
> spam method du jour is to HELO with the recipient's host name or IP (as
> a string). A cron job adds those to the dns rbl automatically as a
> backup for when the spammers change tactics.

Cool.

> BTW, rbldnsd uses considerably less memory than NTPD. Blocking China and
> Korea is an extremely effective technique. If we ever get a client in
> the PRC, I'll be sure to whitelist them -;)

I think this is a totally bogus solution.  I've had to deal with a situation 
where a client of mine was using an ISP that got blocked.  My client had 
done nothing wrong except to be ignorant about SPEWS and similar "services." 
He bought Internet service from SBC and found that he could not send mail to 
random customers of his.  The old saw about "it is better that 10 guilty go 
free than 1 innocent be hanged" is valid.

> BTW, no spam = no viruses. However, we use mime checks to eliminate
> potentially harmful attachments.

Spam != virus

Use the right tool for the job - AV for virus protection, SA for spam 
protection.

Thomas