Since I had to disable the PTR check in Postfix at Binware because in Spain 90% of mail servers are badly configured and they were all rejected, and now we have lot of spam.
So I decided to install Spamassassin and Clamav to detect and reject some of this spam.
First of all, we need to install needed packages:
apt-get install spamassassin amavisd-new clamav clamav-daemon
We will begin configuring amavisd-new, the configuration files are at /etc/amavis/conf.
In file 20-debian_defaults I changed the header that will be added to each mail processed:
$X_HEADER_LINE = "AntiSpam/Antivirus Scanner at $mydomain";
We need to activate antispam and antivirus check in amavis, this is found in file 15-content_filter_mode. We need to uncomment @bypass_virus_checks_maps and @bypass_spam_checks_maps. The file will look like this: