SPAM Filters

[allan]

How many people run SPAM filters on their servers (as opposed to local SPAM filters). If you do run them, what do you use, and do you get a lot of complaints?

[mgriffin]

We run all incoming mail on shared / reseller servers against 40 or so tests utilizing Declude JunkMail (www.declude.com) which allows us to determine which tests are run and weights tests based on accuracy. (combination of RBL's, general spam tests and external programs)

We very rarely receive complaints due to frequent monitoring of the logs to ensure weighting is adjusted appropriately and the underlying weighted configuration which requires multiple tests to fail before any action is taken against specific messages. In addition, weighting can be customized per domain and if needed, domains can be completely whitelisted. The only two complaints I recall were related to specific mailing lists hosted by a provider who also hosts spammers. I was able to whitelist the specific mailing lists my customers had subscribed to.

- Mike Griffin
Handy Networks, LLC

[allan]

Originally posted by mgriffin
We run all incoming mail on shared / reseller servers against 40 or so tests utilizing Declude JunkMail (www.declude.com) which allows us to determine which tests are run and weights tests based on accuracy. (combination of RBL's, general spam tests and external programs)


Mike are you running sendmail or procmail?

[mgriffin]

Hey Allan-

We run Ipswitch I Mail Server (We do Windows only)

- Mike

[allan]

Originally posted by mgriffin

We run Ipswitch I Mail Server (We do Windows only)


What about UNIX admin's experiences with SPAM software.

[DizixCom]

I used to use rblsmtpd with qmail against spamcops rbl. Eventually, due to too many legitimate missed emails I pulled it.

[ffeingol]

I'm using blackholespam (http://the.groovy.org/blackhole.shtml) to filter the mail with qmail. It's not for hosting, but a dedicated box with a couple of peoples mailboxes.

What I really like is that each person can setup a control file and have the mail filtered how they like. I just have mine marked as spam (it modifies the subject) and then I filter that with my mail client. I can sort through the spam stuff later to double check that I'm not missing something important.

You can also override as "whitehats" for people that you want to allow, even though they are on a host that is marked as spam.

Frank

[dandanfireman]

ORDB's rbl service seems to block many of them. Of course with anything you do to fight spam, there will be customers who complain about you blocking messages for them.

[allan]

Originally posted by dandanfireman
ORDB's rbl service seems to block many of them. Of course with anything you do to fight spam, there will be customers who complain about you blocking messages for them.

That brings up an interesting question -- especially for hosting companies, or others that provide mail as a service to customers. When you develop your spam filtering system are you a little more liberal in what you allow through, so customers do not complain, or do you stop as much as possible?

[dandanfireman]

You have to be more liberal, some customers don't want filtering at all, some want a little, some want a lot. Sometimes you have to go with the lowest common denominator....or just put a stake in the ground and say...this is the way it is. It is easier to place that stake when using ORDB, because the only reason servers get placed there is due to improperly or poorly configured mail servers. Spamcop, spews and others are a much bigger fight.

[LetsFly]

Originally posted by dandanfireman
ORDB's rbl service seems to block many of them. Of course with anything you do to fight spam, there will be customers who complain about you blocking messages for them.

the key to using rbl's is to set them to /warn and that way, a tag will be put in the email header, and your customers and setup a spam filter to block it......we set all rpls to warn other then spamcop and ordb (to reject)

[CipherVendor]

Global filtering may get you into some trouble. A lot of people (believe it or not) want to receive all of the mail addressed to them, including spam.

I've found that having spam assassin setup on the server and each user having the ability to enable/disable filtering works best.

I've also seen brightmail spam filtering in use, it seems to work well.