User and User Group Management in Linux

Users and user groups in Linux-Linux general technology-Linux technology and application information. For details, refer to the following section. The main task of user management is to create a legal user account, set and manage user passwords, modify user account attributes, and delete obsolete user accounts when necessary.

1) Add a new user

In Linux, only the root user can create a new user. The following command creates a user with the login name user1.

# Useradd user1

However, this user is not allowed to log on, because the initial password has not been set for it, and users without a password cannot log on to the system. By default, a user home directory with the same user name will be created in the/home directory.

In Linux, when a user is added, a new group is created. The Group has the same name as the user, and the user is a member of the group. To assign a new user to an existing group, run the following command:

# Useradd-g usergroup1 user1

In this way, the user is a member of usergroup1. If you want to make it belong to another group of usergroup2, use:

# Useradd-G usergroup2 user1

After completing this operation, you should also use the passwd command to set an initial password for it.

2) delete a user

To delete a user, you only need to use a simple command "userdel user name. However, it is best to delete the files that remain on the system. You can use "userdel-r username" to achieve this purpose.

3) Add a group

You can create user groups as needed:

Groupadd <Group Name>

4) delete a group

Similarly, we sometimes need to delete a group. Its command is groupdel.