Modern websites have a lot of traffic. They serve millions or hundreds of thousands concurrent requests coming from clients, users, reliably and promptly. These websites have to return high volumes of the correct application data, video, images, and text to the users without hitches, a task that requires a large amount of computing power. Generally, in modern computing, best practices require increasing the number of servers to scale and meet these high volumes cost-effectively.
After increasing the number of servers, you will still need to ensure that incoming network is efficiently distributed across the server pool or server farm — a group of backend servers meant to provide scaling and offset the high volume of incoming traffic. This is where load balancing comes in. The purpose of a load balancer is to ensure that incoming website traffic is evenly distributed across all these servers, efficiently. Get more information about load balancing right here.
How Does a Load Balancer Work?
Well, now that we know what a load balancer is and what it does, let’s look at how exactly the load balance works. To clearly understand how load balancing works, it helps to think of a load balancer as a traffic cop. In the absence of traffic lights to control traffic, a police officer with the traffic department can step in to perform that task and prevent accidents that would result in the confusion that would ensue without the proper traffic control.
That’s exactly what a load balancer does. Just like that traffic cop, the load balancer sits at the front your server pool and routes user requests across the servers accordingly. It routes client requests to servers with the capability to fulfil those requests in a way that ensures maximum capacity utilization and speed. Overworking one particular server degrades performance, and load balancing works to ensure that it doesn’t happen.
If one server is down, load balancing will redirect traffic to the servers remaining online. When the server is fixed, or a new one is introduced, the load balancer will know and automatically start sending client requests to it. Load balancing helps websites remain online even when some of the servers go down. It ensures that services are not affected.
Do You Need Load Balancing?
Often, when people hear about load balancing, they ask whether they need it or inquire about situations that may lead to them needing a load balancer. On whether you need load balancing, the answer is in the affirmative. Secondly, you will always need load balancing. There are no specific situations that may lead to one requiring or not requiring the services of a load balancer because eventually, all websites face traffic challenges.
Even if you have a single backend, you will still need a load balancer. The benefit isn’t completely about distribution or balancing; it’s about having a control point in front of your services. Having a control point gives you the ability to manage your traffic flow, add filtering rules, and alter backends during deploy. It gives you a high level of sustainable availability which you need as your website experiences growth.