Fail2ban
From Federal Burro of Information
quick guide:
http://www.pontikis.net/blog/fail2ban-install-config-debian-wheezy
apt-get install fail2ban vi /etc/fail2ban/jail.local
[DEFAULT] ignoreip = 127.0.0.1 82.192.71.9 95.211.46.207 bantime = 86400 destemail = you@your-email.com banaction = iptables-multiport action = %(action_mwl)s # JAILS [ssh] enabled = true maxretry = 3