Spam Revisited

[LuKreme]

On 5-Dec-2006, at 13:43, Robert Cerny wrote:
> Henry,
> you should fight with SPAM on MTA level at first. There is a couple  
> of techniques which you can very easily implement. I would start  
> with implementing of RBL checks, namely zen.spamhaus.org is very  
> valuable for us. Secondly, you can implement header checks, which  
> also work very well. As a third step, you should tight a little bit  
> motre the postfix setup, let say to ignore mails from servers which  
> don't have correct fqdn or which doesn't communicate correctly.
> You should find all this settings on the postfix.org site.

Tight now, the biggest spam-blocker on my mailserver is greylisting.   
Yeah, it blocks more stuff than even Zen does.

> As a last step, I can only recommend using postgrey. There is a few  
> howto's on the web hot to install in on Mac OS X Server.

postgrey really is a (nearly) magic bullet, though it too takes time  
tweaking and adding the clueless hosts that you actually find you DO  
want email from.

That said, procmail on the server could do a lot:

# Subject or To contains Henry Wloch
:0
* 9876543210^0 ^Subject:.*Henry Wloch
* 9876543210^0 TO_*Henry Wloch
/dev/null

# IP 12.34.56.789 blacklisted
:0
* ^/Received:.*12.34.56.789
/dev/null

where 12.34.56.789 represents the IP address of your Xmas bomber.


-- 
Clark's Law: Sufficiently advanced cluelessness is indistinguishable  
from malice
Clark Slaw: Anything that has been severely damaged or destroyed by  
application of Clark's Law