[Spambayes] Bouncing Spam

[Neale Pickett]

So then, Steve Atkins <steve@blighty.com> is all like:

> The only way to safely bounce spam is to drop it with a permanent
> (5xx) rejection at an appropriate point in the SMTP transaction at the
> first point it enters your network (i.e. if your secondary MX accepts
> it, don't reject the delivery to your primary).

This appears to actually work.  I set up 5xx rejection for certain MAIL
FROM address patterns, with the hopes that spammers would think I had no
valid addresses on my box, and I actually do see the attempts fall off
over time.  Check out the red line:

  http://woozle.org/stats/spam.html

(sorry about the log scale, it doesn't look like much otherwise)

The spikes are when I add new address patterns to the blacklist--I just
added a bunch of them a few days ago, and probably around mid-October.

The other nice thing about doing it this way is that the message never
gets sent to you, so your bandwidth isn't being used up by it, nor is
your disk space.

It's sort of like the graph you'd expect to see of the roach deaths per
day in a house.  You fumigate, a lot of roaches die, and then slowly
rebuild their numbers.  Then you fumigate again, they die again, etc.

Neale