Restrict Users to Use Old Passwords This is very useful if you want to disallow users to use same old passwords. The old password file is located at /etc/security/opasswd. This can be achieved by using PAM module. [root@localhost ~]# cat /etc/pam.d/system-auth #%PAM-1.0 # This file is auto-generated. # User changes will be destroyed the next … Continue reading RESTRICT USERS TO USE OLD PASSWORDS