sudo apt update && sudo apt install fail2ban
sudo yum install epel-release && sudo yum install fail2ban
sudo systemctl enable --now fail2ban
编辑 /etc/fail2ban/jail.local（若不存在则新建）：
[Definition]
allowipv6 = auto
[DEFAULT]
ignoreip = 127.0.0.1/8 ::1
[sshd]
enabled = true
port = 22
filter = sshd
logpath = /var/log/auth.log
maxretry = 5
findtime = 10m
bantime = 24h
ignoreip = 127.0.0.1/8 192.168.1.0/24
maxmatches = 3
[mysql]
enabled = true
port = 3306
filter = mysqld-auth
logpath = /var/log/mysql/mysql.log
maxretry = 6
bantime = 3600
maxmatches = 3
findtime = 10m
重启 Fail2ban
sudo systemctl restart fail2ban
查看运行状态
sudo fail2ban-client status
sudo fail2ban-client status sshd # 检查SSH监狱
sudo fail2ban-client status mysql # 检查MySQL监狱
sudo fail2ban-client status laravel # 检查Laravel监狱
测试正则匹配（调试用）
sudo fail2ban-regex /var/log/auth.log /etc/fail2ban/filter.d/sshd.conf