modify user login
usermod utility modifies user login
information on the system.
Default values are taken from the information provided in the /etc/usermgmt.conf file, which, if running as root, is created using the built-in defaults if it does not exist.
After setting any defaults, and then reading values from /etc/usermgmt.conf, the following command line options are processed:
- Sets the comment field (also, for historical reasons known as the GECOS field) which will be added for the user, and typically will include the user's full name and, perhaps, contact information for the user.
- Sets the home directory to home-directory without
populating it; if the
-moption is specified, tries to move the old home directory to home-directory.
- Sets the time at which the account expires. It should be entered in the form “month day year”, where month is the month name (the first three characters are sufficient), day is the day of the month, and year is the year. Time in seconds since the Epoch (UTC) is also valid. A value of 0 can be used to disable this feature. This value can be preset for new users using the expire field in the /etc/usermgmt.conf file. See usermgmt.conf(5) for more details.
- Sets the time at which the password expires. See the
- Appends the user to the given groups in the
-Sare mutually exclusive.
-ggid | name |
- Gives the group name or identifier to be used for the user's primary
group. If this is the special string
usermodcreates a group with the same ID as the UID; if such a group already exists a warning is given and no group is created. Groups can be preset for all users by using the group field in the /etc/usermgmt.conf file. See usermgmt.conf(5) for more details.
- This option sets the login class for the user being created. See login.conf(5) for more information on user login classes. This value can be preset for all users by using the class field in the /etc/usermgmt.conf file. See usermgmt.conf(5) for more details.
- Gives the new user name. It must consist of alphanumeric characters, or
the characters ‘
-’ or ‘
- Moves the home directory from its old position to the new one. If
-dis not specified, the new-user argument of the
-loption is used; one of
- Allows duplicate UIDs to be given.
- Specifies a password encrypted with encrypt(1) for the user. This password can then be changed by using the chpass(1) utility. This value can be preset for all users by using the password field in the /etc/usermgmt.conf file. See usermgmt.conf(5) for more details.
- Sets the secondary groups the user will be a member of in the
/etc/group file. Setting
secondary-group to an empty value (e.g. '') removes
the user from all secondary groups.
-Gare mutually exclusive.
- Specifies the login shell for the user. This value can be preset for all users by using the shell field in the /etc/usermgmt.conf file. See usermgmt.conf(5) for more details.
- Unlock the account by removing the trailing
-’ from the user's shell and the ‘
*’ prefix from the password.
-Zare mutually exclusive and cannot be used with
- Specifies a new UID for the user. Boundaries for this value can be preset for all users by using the range field in the /etc/usermgmt.conf file. See usermgmt.conf(5) for more details.
- Enables verbose mode - explain the commands as they are executed.
- Lock the account by appending a ‘
-’ to the user's shell and prefixing the password with ‘
-Uare mutually exclusive and cannot be used with
Once the information has been verified,
pwd_mkdb(8) to update the user database. This is run in the
background and, at very large sites, could take several minutes. Until this
update is completed, the password file is unavailable for other updates and
the new information is not available to programs.
usermod utility exits 0 on
success, and >0 if an error occurs.
chpass(1), group(5), passwd(5), usermgmt.conf(5), pwd_mkdb(8)
Other implementations of the
utility use the inactive-time parameter to refer to
the maximum number of days allowed between logins (this is used to lock
"stale" accounts that have not been used for a period of time).
However, on OpenBSD systems this parameter refers
instead to the password change time. This is due to differences in the
database compared to other operating systems.
usermod utility first appeared in
usermod utility was written by
Alistair G. Crooks