FreeRADIUS is a popular open-source RADIUS server that provides centralized AAA (authentication, authorization and accounting) services for network access. It can handle a large number of concurrent sessions and can be used for various purposes, including wireless network authentication and VPN access.

In my previous post, I talked about how to build a high-performance and high-availability radius cluster. Using NGINX for load balancing is core to that design.

Load balancing is a crucial aspect of any network infrastructure, and it is even more critical when it comes to authentication and authorization systems like FreeRADIUS, where unavailability can result in the inability to connect to key networks or systems. Load balancing helps distribute the workload across multiple servers, improving performance and ensuring high availability.

NGINX is a high-performance web server that can also be used as a reverse proxy, load balancer, and HTTP cache. It is known for its scalability, reliability, and performance, making it a great choice for FreeRADIUS load balancing.

Setting up FreeRADIUS load balancing with NGINX Plus is actually really straightforward. Follow these steps:

1. Install FreeRADIUS on multiple servers. I use multiple docker containers, each running a FreeRADIUS instance. For ease of configuration in NGINX I use the same radius ports (1812, 1813 & 1814) on all the radius instances.
2. Install NGINX Plus as a reverse proxy on a separate server. You can make this design even more resilient by using multiple NGINX instances running on the same anycast IP address.
3. Configure NGINX to balance the incoming RADIUS requests between the FreeRADIUS servers. Multiple different load balancing scenarios can be used. I prefer to use the round-robin approach, in order to spread the workload equally amongst available FreeRADIUS instances

In summary, using NGINX for FreeRADIUS load balancing can significantly improve the performance and reliability of your network’s authentication and authorization system. It is a cost-effective and scalable solution that can handle large amounts of traffic and ensure high availability. If you are looking for a load-balancing solution for FreeRADIUS, give NGINX a try!