fail2ban是一款非常实用的安全软件，通过监视系统日志，设置错误登陆次数，可阻挡暴力密码攻击。
1.安装epel
yum install epel-release -y
2.安装fail2ban
yum install fail2ban -y
3.配置
cd /etc/fail2ban/
cp jail.conf jail.local
vim jail.local
[DEFAULT]
bantime = 3600
[sshd]
enabled = true
maxretry = 3
4.启动
systemctl start fail2ban
systemctl enable fail2ban
5.查看日志
fail2ban-client status
tailf /var/log/fail2ban.log