Well, today I studied some new points about blocking spams, lots of ways, I chosed one, I don’t know how effecient is it. I added some spice to my mail server. Let’s see how….
There are lots of websites providing different types of databases to let your spam blockers how to distinguish between spams and good e-mails,
Some ways are like DNS Lookups for bogus IP addresses, using dummy SMTP servers, using deferral SMTP daemons, firewalling and blocking bogus spam senders, They way I have chosen today was blocking IP addresses from TCPSERVER which handles my mail server services, the TCPSERVER provide TCP connectivity for any TCP based service, I should tell you that my mail server is installed on FreeBSD, so all given information is based on that OS.
those guys who installed qmail with Life With Qmail direction they remember that if they want to give access of connecting to SMTP server to specific network they should do this:
echo ‘127.:allow,RELAYCLIENT=””‘ >> /etc/tcp.smtp
qmailctl cdb
Okay, http://www.spews.org provides you a prepaired cdb that you can download it from http://spfilter.openrbl.org/data/output/DEFAULT.qmail_uce.bz2 , now you are ready to set it , just add your network specific settings and make new cdb, then reload int into your server.
When you download DEFAULT.qmail_uce.bz2 use bunzip command to unzip it and add it to current tcp.smtp follow these steps:
bunzip DEFAULT.qmail_uce.bz2
use vi DEFAULT.qmail_uce and replace all allow keywords to deny
cat DEFAULT.qmail_uce >> /etc/tcp.smtp
qmailctl cdb
I kept my eyes on the server to see changes. it blocks more than 2/3 of spams on my network.
Remember that its not the end, you should check http://www.spews.org/ occasionally for new updates.