SSH brute force 차단 rule 추가

firewall-cmd --permanent --add-rich-rule='rule family="ipv4" service name="ssh" limit value="3/m" accept'

 

firewall-cmd --permanent --add-rich-rule='rule family="ipv4" service name="ssh" drop'

 

firewall-cmd --reload

 

firewall-cmd --list-rich-rules

 

1분 3회 SSH 허용
4번째 시도부터 DROP