How to setup Postfix to fighting spam with PostGrey and RBL in Ubuntu Linux
+ Installing PostGrey
apt-get install postgrey
+ Setup Postfix with PostGrey
vim /etc/postfix/main.cf
Add rules some like these:
smtpd_recipient_restrictions = permit_mynetworks, permit_sasl_authenticated, reject_non_fqdn_hostname, reject_invalid_hostname, reject_non_fqdn_sender, reject_unknown_sender_domain, reject_non_fqdn_recipient, reject_unauth_destination, reject_rbl_client uribl.abuse.ro, reject_rbl_client zen.spamhaus.org, reject_rbl_client bl.spamcop.net, reject_rbl_client cbl.abuseat.org, check_policy_service inet:127.0.0.1:10023, permit
+ Restarting PostGrey and Postfix
/etc/init.d/postgrey restart /etc/init.d/postfix restart