1.passwd命令
[root@rhel7 skel]# passwd -n -w -x rusky
Adjusting aging data for user rusky.
passwd: Success 说明：
-n : a minimal usage period of days ---3天后用户才能修改密码
-x : an expiry after days ----5天后密码自动过期
-w : a warning is generated days before expiry ---离密码过期时间2天内提示用户
2.chage -l命令
Showing Password Expiry Information with chage -l
[root@rhel7 skel]# chage -l rusky
Last password change : Jun ,
Password expires : Jun , --密码过期时间
Password inactive : never
Account expires : never
Minimum number of days between password change :
Maximum number of days between password change :
Number of days of warning before password expires :
如果时间小于（Minimum number of days between password change : 3），则不允许修改密码。
[rusky@rhel7 ~]$ passwd
Changing password for user rusky.
Changing password for rusky.
(current) UNIX password:
You must wait longer to change your password
passwd: Authentication token manipulation error
[rusky@rhel7 ~]$ [lxj@rhel7 ~]$ su - rusky
Password:
Warning: your password will expire in day --提示密码1天后到期
Last login: Mon Jun :: EDT on pts/