iptables -F
iptables -X
iptables –I INPUT –p tcp –dport 21 –i enp0s3 –m state –state NEW –m recent –set
iptables –I INPUT –p tcp –dport 21 –i enp0s3 –m state –state NEW –m recent –update –seconds 60 –hitcount 3 –j
DROP
iptables -I INPUT –p tcp –dport 21 –m state –state NEW –j ACCEPT