Creating, Modifying, and Deleting User Accounts

In this lesson, we will follow the lifecycle of a user account on a Linux/Unix system from creation, through modification, to deletion. We will also cover how to manage user groups.

Creating a User Account

useradd (Create New User Account) Let's start by creating a new user account named john:

Here is a breakdown of what that command does:

• useradd: This is the command used to create a new user account.
• -m: This option instructs useradd to create a home directory for the new user. The home directory will be created under /home with the name of the user, in this case /home/john.
• -s /bin/bash: This option sets the login shell for the new user. Here, /bin/bash is specified as the login shell, which means that the Bash shell will be launched whenever john logs into the system.
• john: This is the name of the user account being created.

We can run list the contents of /home and should see the users new home directory:

Additionally, we can switch to the john user by running the following command:

This will show us that we have switch to the john user:

We can exit that user by typing 'exit':

This will show that you have switched back to your other user account (in our labs it is iacadmin):

Understanding the /etc/passwd File

The /etc/passwd file is a text file that describes user account information. Each line in the file represents a single user account and contains seven fields separated by colons (:). Here's the structure:

• username: The name of the user.
• password: An x character indicates that encrypted…