Load balancers have the power to optimize speed and performance on a variety of different server-dependent technologies such as networks, software platforms, applications, and websites, amongst others. But choosing the right load balancer suit your needs can be a challenge. In fact, even seasoned IT professionals struggle to choose the best load balancer because they are overwhelmed by the many options.
There are many different types of load balancers and varying load balancer algorithms to consider. And if you choose the wrong one, you will almost certainly fail to see maximum benefit and return on investment. In fact, you could fail to see any ROI if you select the wrong load balancing solution – a fact that underscores the importance of choosing the right load balancing technology for your needs.
How Do Load Balancers Work?
Before you set off on your search for the best load balancer, it’s important that you have a basic understanding of how load balancing works. In fact, this may be one of the most important tips that you will consider.
A load balancing configuration is focused around a single, central hub server — known as the load balancer — that intercepts incoming client requests. These server requests are then evaluated according to a predetermined algorithm — the load balancing algorithm — and it determines how the incoming server requests are evaluated and dispatched to a cluster or pool of two or more servers.
Load balancers improve speed, performance, and reliability, among other things, by distributing client requests across multiple servers. This prevents overload on a single server — an event that could otherwise cause the server to perform poorly or even crash. Some load balancers also administer server health checks to evaluate a server’s availability and overall performance as part of the load balancing process. This improves user experience while simultaneously ensuring a consistent and high level of performance.
How to Choose the Best Type of Load Balancer for Your Tech
There are several different load balancer types and each is well-suited to one or more technologies. For instance, a network load balancer is going to be the best choice for – you guessed it – network applications. Understanding this concept is really key for choosing the best type of load balancer.
Tips on How to Choose a Load Balancer – Software vs Hardware
Today’s load balancers come in two basic forms: software load balancers and hardware load balancers. Hardware load balancers represent the first generation of this technology, which was initially limited to major corporations and others with deep pockets and large data centers. Hardware load balancers do allow for complete control and the highest degree of security. But they also typically require proprietary software and you’ll need your own data center too. These traits make this option costly and rather impractical for most.
Software load balancers are the best option in a majority of cases, with virtual machines allowing for low overhead, high efficiency and cost effectiveness. Virtual machines comprise both the main hub server and the server pool in the case of software-based configurations. This allows for easy scalability too — a trait that you won’t see with a hardware load balancer.
Tips to Choose a Load Balancer – Terminology
It is important to remember that there is a bit of variation in terms of how companies refer to their load balancer technology. For instance, Company A may offer application load balancers, while Company B offers the same technology but they use the term “elastic application load balancer.”
Finding an apples-to-apples comparison can be difficult when shopping load balancers. For this reason, it’s essential that you read the specs closely to verify that you are acquiring the right load balancer for your needs.
Tips for Finding the Best Load Balancer – Types and Subtypes
There are a few different load balancer types and subtypes to consider. The following is an overview of the most commonly-encountered types and subtypes.
- Application load balancers (or ALBs) can be used with a wide variety of software platforms and applications, from an enterprise software system, to a mobile application or a company web portal. ALBs support HTTP/HTTPS protocol and while operating at OSI Layer 7 (the application layer), it uses features such as header data and packet details to evaluate incoming server requests. Compared to other types of load balancers, the ALB’s evaluation process for incoming client requests is rather comprehensive.
Application load balancers have the ability to perform server health checks too, ensuring consistent performance and a positive user experience. ALBs also support hybrid configurations with incoming client requests distributed to both virtual and on-premise servers. This ability to perform health checks is unique to the ALB.
- Network load balancers (also known as NLBs) are used in conjunction with networks of all types and sizes. NLBs operate at OSI Layer 4 — the transport layer — and they evaluate incoming server traffic using a more cursory approach: the examination of traits such as port and IP. Unlike ALBs, network load balancers do not perform server health checks.
NLBs are ideal for maximizing network performance, especially those with high-volume TCP requests or configurations with multiple ports on an EC2 instance that’s also utilizing container services.
- Elastic load balancers, or ELBs, are a fairly common subtype of load balancer that can include some of the aforementioned types, such as application load balancers and network load balancers. The term “elastic” refers to the load balancer’s scaling capabilities, with resources automatically allocated in a manner that aligns with demand.
- Global server load balancers (GSLBs) — also called geographic load balancers — are a popular subtype involving a network of data centers scattered across different regions of the globe. Like elastic load balancers, the geographic load balancer subtype includes some of the aforementioned types. The server closest to the client handles the request to maximize speed and performance, but beyond this, there is the added benefit of redundancy. If one region is impacted by an adverse event and servers go down, server traffic can be rapidly re-routed to a different data center. Many prefer this type of load balancer for use in conjunction with mission-critical infrastructure, along with backup and recovery.
Once you choose the best load balancer for your server-reliant technology, you’ll need to ensure that you select the ideal load balancing algorithm and configuration. But picking the right LB is the first and most important step.
At Resonate, load balancing is what we do. It’s our specialty and we are always available to help guide clients through the process of choosing a load balancer — one that will maximize performance, improve reliability and help you to maintain a positive user experience. Contact Resonate today and let’s explore how to choose the best load balancer for your needs.