Ajay Nawani wrote:
Below is the more clarification:
Please do not top-post. Mail to list, if you hit "Reply all" I get two copies of same mail which is unnecessary.
Example: My domain: hello.com with MX record mx1.hello.com I'm having three servers as below:
I assume you have correct DNS entries in place so mx1.hello.com has first preference of all MXs. Adjust distance in MX records accordingly..
Server1: Name: mx1.hello.com Platform: Redhat Linux with Qmail. Acting as: Inbound SMTP server for hello.com domain (MX pointer) and forward to pop.hello.com server.
So this server need to run antispam software. I use Spamassassin which works great. Use latest version of spamassassin. You can tweak points for spam rules etc. More you can check on spamassassin website. In qmail-ldap you can use various variables like MAXRCPTCOUNT, RBL, RCPTCHECK, REJECTEXEC, RETURNMXCHECK, SANITYCHECK, SENDERCHECK, TARPITCOUNT, TARPITDELAY. Using these variables you can weed out some spam. If you plan to use spamassassin and simscan, then you should also take a look at QMAILQUEUE environment variable.
Check control files like: badmailfrom, badmailfrom-unknown, badmailpatterns, badrcptto, goodmailaddr.
For details check: http://www.qmail-ldap.org/wiki/Qmail-smtpd http://www.qmail-ldap.org/wiki/QMAILQUEUE http://www.qmail-ldap.org/wiki/Lwql#ldapcluster
Server2: Name: pop.hello.com Platform: Solaris, Qmail-LDAP, Courier-IMAP Acting as: POP3, IMAP Server.
Not sure if you know how to achieve this. But here it is. You can forward all mails to this server from mx1 using either ~control/smtproutes or using mailHost (clustering must be turned on) attribute in LDAP.
Server3: Name: smtp.hello.com Platform: Redhat Linux with Qmail. Acting as: Outbound SMTP Server. I tried ASSP, AVG etc to block spam but none of them are perfect.
It is very difficult to find a "perfect" solution for stopping all spam at the same time loose no ham. As for me qmail-ldap+spamassassin+simscan works great. It is stopping almost 90% spam but at the same time I face odd calls of customers who are loosing ham but that seldom happens. If you decide to use this combination, then take a close look at simscan options.
You may also consider DSPAM+Mysql as suggested by Jacob. I haven't tried it so can't comment on it.
Regards, -- Sameer N. Ingole http://weblogic.noroot.org/ --- Better to light one candle than to curse the darkness.
