radwho

radwho is a command-line utility provided by FreeRADIUS for querying and displaying information about currently active RADIUS sessions. It is particularly useful for administrators who need to monitor and manage RADIUS sessions in real-time.

Key Features of radwho

• Real-time Session Monitoring: Shows active RADIUS sessions.

• Detailed Information: Provides details such as username, NAS (Network Access Server) IP address, session start time, and session duration.

• Command-Line Interface: Suitable for scripting and automation.

Installation

radwho is typically included with the FreeRADIUS server package. Ensure you have the FreeRADIUS server utilities installed to use radwho.

On Debian-based systems:

sudo apt-get install freeradius-utils

On Red Hat-based systems:

sudo yum install freeradius-utils

Basic Usage

The basic syntax for radwho is:

radwho [options]

Example Commands

Display Active Sessions

To display all active RADIUS sessions:

radwho

Output Format

The output of radwho typically includes columns such as:

• Username: The username of the authenticated user.

• NAS-IP-Address: The IP address of the NAS (Network Access Server) where the user is connected.

• Start Time: The time when the session started.

• Session Duration: How long the session has been active.

Here’s an example of how the output might look:

Username       NAS-IP-Address         Start Time           Session Duration
------------------------------------------------------------------------------
alice          192.168.1.1            2024-07-15 10:30:00  1h 15m
bob            10.0.0.5               2024-07-15 09:45:00  2h 30m

Additional Options

• -v, --verbose: Provides more detailed information about each session.

• -h, --help: Displays help information and usage instructions for radwho.

Usage Scenarios

Monitoring Active Sessions

Administrators can use radwho to monitor and manage active RADIUS sessions. It helps in identifying currently connected users, their session details, and monitoring session durations.

Scripting and Automation

Since radwho provides a command-line interface, it can be incorporated into scripts and automated monitoring systems to periodically check and report on active RADIUS sessions.

Conclusion

radwho is a valuable tool for administrators managing RADIUS servers, providing insights into active user sessions and facilitating real-time monitoring and management. By leveraging radwho, administrators can ensure smooth operation of authentication services and promptly address any session-related issues.