Addons for anti-spam..

[lhpsobral]

Has anyone used these services for anti-spam razo2, pyzor and dcc ??

[overseer]

Spamhaus (free API key) and rspamd (free to start for basic services) are effective. Also, just tuning Postfix for anti-UCE will get you miles down the road.

[changlee]

Do you have a tutorial on this please?

[overseer]

Spamhaus DQS:
https://docs.spamhaus.com/datasets/docs/source/40-real-world-usage/MTAs/020-Postfix.html

Rspamd:
https://forum.centos-webpanel.com/how-to/(howto)-install-rspamd/

Postfix:
https://www.akadia.com/services/postfix_uce.html
https://www.linuxbabe.com/mail-server/block-email-spam-postfix