usermod − modify a user’s login information on the system


usermod [ -uid [-o]] [-group] [ -group [ , group...]] [ -dir [-m]] [-shell] [-comment] [-new_name] [-inactive] [-expire] [-A authorization [, authorization]] [-P profile [, profile]] [-R role [, role]] login


The usermod utility modifies a user’s login definition on the system. It changes the definition of the specified login and makes the appropriate login-related system file and file system changes.

The system file entries created with this command have a limit of 512 characters per line. Specifying long arguments to several options may exceed this limit.


The following options are supported:
-A authorization

One or more comma separated authorizations as deined in auth_attr(4). Only a user or role who has grant rights to the authorization can assign it to an account. This replaces any existing authorization setting.

-c comment

Specify a comment string. comment can be any text string. It is generally a short description of the login, and is currently used as the field for the user’s full name. This information is stored in the user’s /etc/passwd entry.

-d dir

Specify the new home directory of the user. It defaults to base_dir/login, where base_dir is the base directory for new login home directories, and
is the new login.

-e expire

Specify the expiration date for a login. After this date, no user will be able to access this login. The expire option argument is a date entered using one of the date formats included in the template file /etc/datemsk. See getdate(3C).

For example, you may enter 10/6/90 or October 6, 1990. A value of ’’ ’’ defeats the status of the expired date.

-f inactive

Specify the maximum number of days allowed between uses of a login ID before that login ID is declared invalid. Normal values are positive integers. A value of 0 defeats the status.

-g group

Specify an existing group’s integer ID or character-string name. It redefines the user’s primary group membership.

-G group

Specify an existing group’s integer "ID" "," or character string name. It redefines the user’s supplementary group membership. Duplicates between group with the -g and
-G options are ignored. No more than NGROUPS_UMAX groups may be specified as defined in <param.h>.

-l new_logname

Specify the new login name for the user. The new_logname argument is a string no more than eight bytes consisting of characters from the set of alphabetic characters, numeric characters, period (.), underline (_), and hypen (). The first character should be alphabetic and the field should contain at least one lower case alphabetic character.
A warning message will be written if these restrictions are not met. A future Solaris release may refuse to accept login fields that do not meet these requirements. The new_logname argument must contain at least one character and must not contain a colon (:) or NEWLINE (\n).


Move the user’s home directory to the new directory specified with the -d option. If the directory already exists, it must have permissions read/write/execute by group, where group is the user’s primary group.


This option allows the specified UID to be duplicated (non-unique).

-P profile

One or more comma-separated execution profiles defined in auth_attr(4). This replaces any existing profile setting.

-R role

One or more comma-separated execution profiles defined in auth_attr(4). This replaces any existing role setting.

-s shell

Specify the full pathname of the program that is used as the user’s shell on login. The value of shell must be a valid executable file.

-u uid

Specify a new UID for the user. It must be a non-negative decimal integer less than MAXUID as defined in <param.h>. The UID associated with the user’s home directory is not modified with this option; a user will not have access to their home directory until the UID is manually reassigned using chown(1M).


The following operands are supported:

An existing login name to be modified.


In case of an error, usermod prints an error message and exits with one of the following values:


The command syntax was invalid. A usage message for the usermod command is displayed.


An invalid argument was provided to an option.


The uid given with the -u option is already in use.


The password files contain an error. pwconv(1M) can be used to correct possible errors. See passwd(4).


The login to be modified does not exist, the group does not exist, or the login shell does not exist.


The login to be modified is in use.


The new_logname is already in use.


Cannot update the /etc/group or /etc/user_attr file. Other update requests will be implemented.


Insufficient space to move the home directory (-m option). Other update requests will be implemented.


Unable to complete the move of the home directory to the new home directory.



system file containing group definitions


system file of date formats


system password file


system file containing users’ encrypted passwords and related information


system file containing additional user and role attributes


See attributes(5) for descriptions of the following attributes:

Image /var/www/mancx/application/src/../www/___/img/man1/man1/usermod1.png


passwd(1), users(1B), chown(1M), groupadd(1M), groupdel(1M), groupmod(1M), logins(1M), pwconv(1M), roleadd(1M), roledel(1M), rolemod(1M), useradd(1M), userdel(1M), getdate(3C), auth_attr(4), passwd(4), attributes(5)


The usermod utility modifies passwd definitions only in the local /etc/passwd and /etc/shadow files. If a network nameservice such as NIS or NIS+ is being used to supplement the local files with additional entries, usermod cannot change information supplied by the network nameservice. However usermod will verify the uniqueness of user name and user ID against the external nameservice.

The usermod utility uses the /etc/datemsk file, available with SUNWaccr, for date formatting.