amavisd-new genrsa /var/lib/dkim/domain.pem 1024 chown amavis:amavis /var/lib/dkim/domain.pem chmod 0400 /var/lib/dkim/domain.pem nano /etc/amavis/conf.d/50-user dkim_key("domain", "dkim", "/var/lib/dkim/domain.pem"); "domain" => { d => "domain", a => 'rsa-sha256', ttl => 10*24*3600 }, systemctl restart amavis amavisd-new showkeys amavisd-new testkeys