change user password expiry information
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.
which apply to the chage command are:
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
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.
number −1 as the EXPIRE_DATE will remove
an account expiration date.
Display help message and
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
number −1 as the INACTIVE will remove an
Show account aging
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.
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.
number −1 as MAX_DAYS will remove
checking a password's validity.
Apply changes in the
CHROOT_DIR directory and use the configuration files
from the CHROOT_DIR directory.
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 [ ]
chage program requires a shadow password file to be
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.
configuration variables in /etc/login.defs change the
behavior of this tool:
User account information.
Secure user account
chage command exits with the following values:
invalid command syntax
can't find the shadow password