DenyHosts
You can install denyhosts on most distros to reduce SSH attacks on your serversCentOS
# yum --enablerepo=rpmforge install denyhosts # service denyhosts start
Ubuntu
# aptitude install denyhosts
Verify
# ps aux | grep deny root 1075 0.0 0.9 9756 4596 ? S 11:46 0:00 python /usr/sbin/denyhosts --daemon --purge --config=/etc/denyhosts.conf
REFERRERS
SystemSecurity