Modern business network architecture has a complicated structure and a lot of devices can connect simultaneously which is a convenient feature for hackers and anybody who has illegal intentions. To solve this problem people invented one exciting solution. Radius server (aaa server), which can provide 3 functions of protection: authentication, authorization, and accounting. Every step on the system will be logged and all entries, and points of input are under control.
RADIUS server
FreeRADIUS — is an exceptional RADIUS server that offers centralized authentication and authorization services for devices, including switches, routers, VPN gateways, and WiFi access points. Its unique ability to manage user access to network resources based on various parameters, such as identity, location, device characteristics, and time of day, makes it a versatile solution for enterprise, academic, and service provider environments.
The server supports multiple authentication methods and can integrate with external databases like SQL, LDAP, and Kerberos for efficient user and device information storage and retrieval. With its scalability, flexibility, and robustness, FreeRADIUS remains a top choice for organizations seeking a reliable and customizable RADIUS solution.
Install FreeRADIUS
Before installing any software, we need to update the index and package on AlmaLinux:
sudo dnf update -y
Install the necessary package for the RADIUS server:
sudo dnf install freeradius
After installation, you need to configure the server according to your requirements. Configuration files we can find with the command below:
sudo nano /etc/raddb/radiusd.confBut you can still use anything, a convenient text editor. Open the file and look at the parameters: logging, authentication protocol, and ports. All settings can be modified for your purposes.
Next, create a file with the name “user.conf” in the same directory:
sudo touch /etc/raddb/user.confOpen the file in your text editor using the following command:
sudo nano /etc/raddb/user.confIn the config add the client's devices and shared secret using the following syntax:
client <client IP or hostname> {
secret = <shared secret>
}
Instead of “client IP or hostname” enter what you need credentials and the same thing with the “shared secret”, instead put a very strong password because of its single and fast method to get access to your system.
Notice: that the configuration file determines rules for the client’s device!
Now, we go set up config for a user account: configuring accounts and groups for authentication on the server side, an open—source implementation of the RADIUS protocol. This involves creating user accounts and assigning them group memberships in the database.
sudo nano /etc/raddb/usersAnd paste this:
<username> Cleartext-Password := "<password>"
Replace <username> with the desired username, and <password>with the corresponding password in clear text format. Similarly, open the groups file in your text editor using the following command:
sudo nano /etc/raddb/groupsAnd enter this:
<groupname> User-Name == "<username>"
Start the Radius server: Once the configuration is done, start the server by running the appropriate command. For example, to start the server, you can run:
sudo systemctl start radiusdAnd that’s it!
FreeRADIUS Linux
Configuring the RADIUS server (AAA server) on AlmaLinux is a straightforward process that involves several simple steps. Basic the configuration steps outlined in this article, you can have your FreeRADIUS server up and running in no time. However, it is important to note that there are more advanced configuration options and features available in the software that were not covered in this article.
