As we all know security is quintessential especially for those who are storing sensitive information such as credit card details. I came across a great Linux based FOSS tool which is written in Python and can be a boon for anyone who is worried about illicit ssh access.
The program is know as Fail2Ban. You can configure it to allow maximum number of retries to access you server via ssh. What's more interesting is the ability to send email to a user-defined account whenever you're under attack!