A weak password can be one of the weakest security points of any system. Simple passwords are susceptible to brute-force attacks and long-lived passwords, if they are compromised, provide a wide window of opportunity for malicious activity. Because of this, it's important to ensure that your users choose sufficiently complex passwords and change them regularly. This recipe shows you how to strengthen your system's security by enforcing various restrictions on users' passwords. You'll learn how to specify the minimum complexity requirements for a password, how long before a password must be changed, and how to lock down an account after a number of failed login attempts.
This recipe requires a CentOS system and administrative access, either provided by logging in with the root account or by using sudo.