TestOut Linux Pro Practice Test 2025 – Complete Exam Prep Guide

The command that lists all active user sessions is "who." This command provides information about users who are currently logged into the system. When executed, it displays various details including the username, terminal name, login time, and occasionally the originating IP address if applicable.

Using "who" gives a clear view of all users currently using the system, making it especially useful for system administrators who need to monitor user activity and sessions. It serves as a fundamental tool in user management, helping to ensure that only authorized users are logged in and to investigate any potential issues related to user access.

On the other hand, "users" simply returns the usernames of users currently logged in without additional details. "whoami" shows the username of the current user executing the command, and "sessionlist" is not a standard Linux command. Hence, while those commands may provide useful information in different contexts, "who" is specifically designed to fulfill the requirement of listing all active user sessions.