https://www.vultr.com/docs/enable-ssh-login-notification-on-linux
firewall-cmd --permanent --direct --add-rule ipv4 filter INPUT_direct 0 -p tcp --dport 80 -m state --state NEW -m recent --set
firewall-cmd --permanent --direct --add-rule ipv4 filter INPUT_direct 1 -p tcp --dport 80 -m state --state NEW -m recent --update --seconds 30 --hitcount 100 -j REJECT --reject-with tcp-reset
firewall-cmd --reload
find /home -type f -perm 0400 -exec bash -c 'chmod 755 "$1"' _ {} \;
firewall-cmd --permanent --add-service=smtp firewall-cmd --permanent --add-service=smtps firewall-cmd --permanent --add-service=imap firewall-cmd --permanent --add-service=imaps firewall-cmd --permanent --add-service=pop3 firewall-cmd --permanent --add-service=pop3s sudo firewall-cmd --reload