establish password aging policies

The chage command changes the number of days between password changes and the date of the last password change. This information is used by the system to determine when a user must change his/her password. The /etc/login.defs file defines the site-specific configuration for the shadow password suite including password aging configuration. To disable password aging, enter:

chage -M 99999 userName

To get password expiration information, enter:

chage -l userName

You can also manually specify the information in the /etc/shadow file which has the following fields

{userName}:{password}:{lastpasswdchanged}:{Minimum_days}:{Maximum_days}:{Warn}:{Inactive}:{Expire}:

Note that the “Expire” date is in Unix Time (seconds since Jan 1, 1970)

The chage command is usually easier than manually editing the /etc/shadow file. 

chage –M 60 –m 7 –W 7 <accountname>