chage - change user password expiry information
chage [options] LOGIN
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 options which apply to the chage command are: -d, --lastday LAST_DAY Set the number of days since January 1st, 1970 when the password was last changed. The date may also be expressed in the format YYYY-MM-DD (or the format more commonly used in your area). -E, --expiredate EXPIRE_DATE Set the date or number of days since January 1, 1970 on which the user's account will no longer be accessible. The date may also be expressed in the format YYYY-MM-DD (or the format more commonly used in your area). A user whose account is locked must contact the system administrator before being able to use the system again. Passing the number -1 as the EXPIRE_DATE will remove an account expiration date. -h, --help Display help message and exit. -I, --inactive INACTIVE Set the number of days of inactivity after a password has expired before the account is locked. The INACTIVE option is the number of days of inactivity. A user whose account is locked must contact the system administrator before being able to use the system again. Passing the number -1 as the INACTIVE will remove an account's inactivity. -l, --list Show account aging information. -m, --mindays MIN_DAYS Set the minimum number of days between password changes to MIN_DAYS. A value of zero for this field indicates that the user may change his/her password at any time. -M, --maxdays MAX_DAYS Set the maximum number of days during which a password is valid. When MAX_DAYS plus LAST_DAY is less than the current day, the user will be required to change his/her password before being able to use his/her account. This occurrence can be planned for in advance by use of the -W option, which provides the user with advance warning. Passing the number -1 as MAX_DAYS will remove checking a password's validity. -R, --root CHROOT_DIR Apply changes in the CHROOT_DIR directory and use the configuration files from the CHROOT_DIR directory. -W, --warndays WARN_DAYS Set the number of days of warning before a password change is required. The WARN_DAYS option is the number of days prior to the password expiring that a user will be warned his/her password is about to expire. If none of the options are selected, chage operates in an interactive fashion, prompting the user with the current values for all of the fields. Enter the new value to change the field, or leave the line blank to use the current value. The current value is displayed between a pair of [ ] marks.
The chage program requires a shadow password file to be available. The chage command is restricted to the root user, except for the -l option, which may be used by an unprivileged user to determine when his/her password or account is due to expire.
The following configuration variables in /etc/login.defs change the behavior of this tool:
/etc/passwd User account information. /etc/shadow Secure user account information.
The chage command exits with the following values: 0 success 1 permission denied 2 invalid command syntax 15 can't find the shadow password file
passwd(5), shadow(5).
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