MacLochlainns Weblog

The following are samples of creating, changing, and removing users and groups in Linux. These are the command-line options in the event you don’t have access to the GUI tools.

Managing Users:

Adding a user:

The prototype is:

# useradd [-u uid] [-g initial_group] [-G group[,...]] \
 > [-d home_directory] [-s shell] [-c comment] \
 > [-m [-k skeleton_directory]] [-f inactive_time] \
 > [-e expire_date] -n username

A sample implementation of the prototype is:

# useradd -u 502 -g dba -G users,root \
 > -d /u02/oracle -s /bin/tcsh -c "Oracle Account" \
 > -f 7 -e 12/31/03 -n jdoe

Modifying a user:

The prototype is:

 # usermod [-u uid] [-g initial_group] [-G group[,...]] \
 > [-d home_directory] [-s shell] [-c comment] \
 > [-l new_username ] [-f inactive_time] [-e expire_date]
 > username

A sample implementation of the prototype is:

# usermod -u 502 -g dba -G users,root
 > -d /u02/oracle -s /bin/bash -c "Senior DBA"
 > -l sdba -f 7 -e 12/31/03 jdoe

Removing a user:

The prototype is:

# userdel [-r] username

A sample implementation of the prototype is:

# userdel -r jdoe

Managing Groups:

Adding a group:

The prototype is:

# groupadd [-g gid] [-rf] groupname

A sample implementation of the prototype is:

# groupadd -g 500 dba

Modifying a group:

The prototype is:

# groupmod [-g gid] [-n new_group_name] groupname

A sample implementation of the prototype is:

 # groupmod -g 500 -n dba oinstall

Deleting a group:

The prototype is:

# groupdel groupname

A sample implementation of the prototype is:

# groupdel dba

Installing a GUI Manager for Users and Groups:

If you’re the root user or enjoy sudoer privileges, you can install the following GUI package for these tasks:

yum install -y system-config-users

You can verify the GUI user management tool is present with the following command:

which system-config-users

It should return this:

/bin/system-config-users

You can run the GUI user management tool from the root user account or any sudoer account. The following shows how to launch the GUI User Manager from a sudoer account:

sudo system-config-users

As always, I hope this helps those trying to figure out the proper syntax.