What is a Load Balancer?
A load balancer is a device or software that distributes incoming network traffic across multiple servers to ensure no single server is overwhelmed. It improves application availability, reliability, and performance by spreading the workload evenly.
How Does Load Balancer Work?
Load balancers sit between users and your backend servers, routing each incoming request to the most appropriate server based on algorithms like round-robin, least connections, or server health. If one server becomes unavailable, the load balancer automatically redirects traffic to healthy servers, providing fault tolerance and high availability.
Load balancing is essential for high-traffic websites and applications that require more resources than a single server can provide. It enables horizontal scaling by allowing you to add more servers as traffic grows. Load balancers also handle SSL termination, session persistence, and health checks. Both hardware and software load balancers are available, with software options like Nginx and HAProxy being popular choices.