Re: [Dspam-user] Dspam with amavis and Zimbra

[Garith D. <ga...@sa...>]

Hi,

I'd like to throw in my thoughts on the subject.

No disrespect to Zimbra but I don't see its forte being anti-spam. Its an extra service that could work for some people - as per user filtering isn't its focus eventually I've found a tug-of-war scenario where emails are marked spam then ham as some emails are spam to one user and ham to another. That said, I've been running a few instances of Zimbra for many years now and very happy with everything it offers (collaboration being one of its many strengths). I'd recommend you setup a mail gateway that does all the anti-spam/anti-virus work for you.

I have a postfix/dspam/clamav/mailscanner/baruwa setup that does per user anti-spam filtering and I've see fantastic results (in excess of 95% accuracy for some users).

Since Zimbra has the functionality of acting on the "hook" of the "Junk" folder anything a user adds or removes from the folder can be redirected to dspam and trained there using the dspam signature. I do this in Zimbra by using:

zmprov mcf zimbraSpamHeader X-DSPAM-Result
zmprov mcf zimbraSpamHeaderValue Spam
zmprov mcf zimbraSpamIsSpamAccount spa...@ex...
zmprov mcf zimbraSpamIsNotSpamAccount not...@ex...

You can then setup a forwarder for the {notspam,spam}-tr...@ex... addresses and point it to your dspam mail gateway.

/etc/aliases on my mail gateway then pipes those addresses to a script that finds the original signature and associated address (MySQLUIDInSignature does this for you apparently but I only discovered this after the system was live) and then summons dspam to train the filter using the original email address it was sent to.

For incoming email I have dspam doing externallookups using zimbra's ldap - great for making sure you keep all training per account + all it's aliases.

Over and out,
-- 

Garith Dugmore 
Senior System Administrator 
South African Astronomical Observatory 
and Southern African Large Telescope