How to Clear the Password History in AIX
By Chris Hoffman
Updated September 28, 2017
IBM’s AIX UNIX operating system can force users to change their passwords at regular intervals. AIX can remember a user account’s previous passwords, preventing the user from changing the password back to a recently used password and forcing the user to create a new password. Each user account on the system has its own password history, and you can set the number of passwords AIX should remember. If you want to clear a user’s password history, you can temporarily set the amount of passwords to remember to zero, forcing AIX to forget the user account’s password history.
Type “su” at the AIX terminal prompt and press “Enter” to become the root user if you’re already logged in, or type “root” at the login prompt and press “Enter” to log in as the root user.
Type the root account's password at the password prompt and press “Enter” to authenticate.
Type “chuser histsize=0 username” at the terminal prompt, replacing “username” with the name of the user account you want to clear the password history for, and press “Enter.”
Type “chuser histsize=# username” at the terminal prompt, replacing “username” with the name of the user account you cleared the password history for and “#” with the number of passwords AIX should remember for the user, then press “Enter.”