RE: [cobalt-users] Raq550: Need Spam Filter advice

["Dan Kriwitsky" <list1@xxxxxxxxxxxxxxxxxxxx>]

> I need help fighting spam and I want to install an Anti-Spam 
> program on the Raq550.  I need a program that will deny 
> emails - not just filter them to a dump account.  I want to 
> filter by the link that is embedded in the email too - not 
> just the text.  Many of these spam messages come from many 
> different IPs and I have manually blocked hundreds.  They do 
> seem to link to the same few websites.  It is these emails 
> that I want to deny so that they get the messages back.
> 
> Any programs that will allow me to do this?

Any of the DNSBL blocking lists will allow you to do this.
Spamhaus, NAJBL, ORDB, etc.
Any of the filtering programs that require you to download the spam to
look at the body first get tricky. If you're blocking anywhere after the
SMTP connection and doing anything except dropping the connection you
start getting into trying to send the spam back to the From or
return-path which are almost always faked. You end up sending the spam
to an innocent party. (AOL does that.) Take a look at some of the
resources at http://spamlinks.openrbl.org/filter-server.htm#sendmail 
Instructions for editing the sendmail.cf or using the features via m4
are in the archives or on the Sendmail site.
-- 
C2003 Dan Kriwitsky

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