To add a user, there are two standard utilities:
adduser - interactive
useradd - scriptable
Try them both and find out. One will walk you through the process of adding a
user step by step. In other words, it will prompt you for all of the information
that you may want to add for each user. The other will make you use cute little
switches to add the details for your new user.
adduser:
adduser [options] [--home DIR] [--shell|-s SHELL] [--no-create-home]
[--uid ID] [--firstuid ID] [--lastuid ID] [--ingroup GROUP | --gid ID]
[--disabled-password] [--disabled-login] [--gecos GECOS]
[--add_extra_groups] user
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useradd:
useradd [options] LOGIN
adduser will prompt you for all of the new users information. i.e. password,
fullname, etc. useradd will prompt you for nothing, and you'll have to set your
new user up on your own.
addgroup wheel
usermod -G wheel user
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To add a group, there are two standard utilities:
addgroup - interactive
groupadd - scriptable
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Example of adding group "wheel" and assigning a user "user" to the group:
addgroup wheel
usermod -G wheel user