vim /etc/amavis/conf.d/50-user
$log_level = 5; $sa_debug = 1;
service amavis restart service spamassasin restart
https://forum.iredmail.org/topic12681-iredmail-support-enable-spamassassin.html
https://docs.iredmail.org/debug.amavisd.html
https://docs.iredmail.org/file.locations.html#amavisd