Spam Control

[amitbiswas]

Hi, I am using Release 5.0.2_GA_1975.UBUNTU6 UBUNTU6 FOSS edition and finding some problem with spam control. At this stage zimbra running on default setup, I have not done any customization and forwarding all spam to spam training account for last 2 months but unfortunately I am getting more spam mail then what I use to on my old postfix, amavis, spamassassin and greylist combination. I am looking for some suggestion how to minimize the spam into users inbox. Any help on this will be much appreciated. Thanks in advance.

[mmorse]

Lots of tidbits here: Improving Anti-spam system - Zimbra :: Wiki

[mshanley]

Hi there...

I have been running windows mail servers for a few years. This is my first Linux mail server.. currently running 6.0 GA on Ubuntu 804lts. 32bit.

I have found these DNSBL Lists to work VERY well..
zen.spamhaus.org
bl.spamcop.net
dnsbl-1.uceprotect.net
ix.dnsbl.manitu.net
dyna.spamrats.com
noptr.spamrats.com
all.rbl.jp
safe.dnsbl.sorbs.net
b.barracudacentral.org
psbl.surriel.com
dnsbl.ahbl.org
dnsbl.njabl.org
bhnc.njabl.org
dnsbl.dronebl.org
ubl.unsubscore.com


Please feel free to check statistics with low false postivies from these sites.

DNS Black list compared - look up dnsbl performance info
Blacklists Compared, 22-Aug-09
and
DNSBL Resource: Statistics Center


I did not include spamhaus below as i have it running at the firewall..on another box

FYI..
Do not use DSBL = offline
Use only Zen for Spamhaus
CBL is included in Zen, so no need to use it by itself.


I added these rules by doing this...

zmprov mcf +zimbraMtaRestriction "reject_rbl_client dnsbl-1.uceprotect.net"
zmprov mcf +zimbraMtaRestriction "reject_rbl_client ix.dnsbl.manitu.net"
zmprov mcf +zimbraMtaRestriction "reject_rbl_client dyna.spamrats.com"
zmprov mcf +zimbraMtaRestriction "reject_rbl_client noptr.spamrats.com"
zmprov mcf +zimbraMtaRestriction "reject_rbl_client all.rbl.jp"
zmprov mcf +zimbraMtaRestriction "reject_rbl_client safe.dnsbl.sorbs.net"
zmprov mcf +zimbraMtaRestriction "reject_rbl_client b.barracudacentral.org"
zmprov mcf +zimbraMtaRestriction "reject_rbl_client psb.surriel.com"
zmprov mcf +zimbraMtaRestriction "reject_rbl_client dnsbl.ahbl.org"
zmprov mcf +zimbraMtaRestriction "reject_rbl_client dnsbl.njabl.org"
zmprov mcf +zimbraMtaRestriction "reject_rbl_client bhnc.njabl.org"
zmprov mcf +zimbraMtaRestriction "reject_rbl_client dnsbl.dronebl.org"
zmprov mcf +zimbraMtaRestriction "reject_rbl_client ubl.unsubscore.com"


verify rules added
zmprov gacf | grep zimbraMtaRestriction

then use
zmmtactl restart

Cheers!