Contenido

postgrey

apt-get install postgrey
netstat -anp | grep 60000
 tcp        0      0 127.0.0.1:60000         0.0.0.0:*               LISTEN     18478/postgrey.pid

/etc/postfix/main.cf

check_policy_service inet:127.0.0.1:60000

/etc/postfix/main.cf

reject_rbl_client sbl-xbl.spamhaus.org

Significantly reduce the amount of spam

whitelists: accept mail from known, trusted senders.
blacklists: refuse mail from undesired senders.
challenge/response: allows unknown senders which aren't on the whitelist or blacklist the chance to confirm that their message is legitimate (non-spam).
tagged addresses: special-purpose e-mail addresses such as time-dependent addresses, or addresses which only accept certain kinds of communication. These increase the transparency of TMDA for unknown senders by allowing them to safely circumvent the challenge/response system.