Web Server Load balancing for eCommerce websites – a basic guide to traffic management

For keeping a live ecommerce website up and running, there is a significant amount of investment required in setting up the backend IT infrastructure and its management.

As an ecommerce business owner, one is aware of the fact that this is a necessary investment. Why? Because the losses suffered when a website goes down are debilitating, as explained in our post on how to keep ecommerce websites up and running through 24×7 IT monitoring and support.

Surge in ecommerce website traffic: A boon or bane for your business?

One of the reasons websites experience outage or downtime is due to too much traffic—more than the website can handle. That’s a double-edged sword for any ecommerce website—any increase in traffic is good news, in fact the larger the better. But sometimes websites may not equipped to handle a sudden and significant jump in traffic, leading to downtime. In such cases, not only are the benefits of increased website traffic lost (your potential customers won’t be able to access your website), there’s loss in brand reputation too.

But is it possible to keep the website operating smoothly while still catering to a surge in traffic? The answer is a resounding ‘Yes’! This is usually done by distributing the burden of increased traffic across resources—a practice known as load balancing.

In this post, we’re going to give you all the introductory info about load balancing and how you can use it to benefit your ecommerce website without being a drain on business costs.

What is server load balancing?   

Wikipedia explains the meaning and scope of load balancing well: “load balancing improves the distribution of workloads across multiple computing resources, such as computers, a computer cluster, network links, central processing units, or disk drives. Load balancing aims to optimize resource use, maximize throughput, minimize response time, and avoid overload of any single resource.”

In this post, we’ll discuss load balancing specifically in the context of managing ecommerce website traffic.

Why is server load balancing important for ecommerce websites?

As the Wikipedia explanation states, load balancing achieves operational speed and efficiency by ensuring no one server is overloaded, even distribution of the load across servers, improvement in the rate of processing and website speed, and ensuring that there is negligible time lag in website response.

So what’s the effect of these features of server load balancing on your ecommerce website?

  • Scalability: Ecommerce websites usually experience a significant jump in traffic during periods of special offers, festive season shopping or the launch of a much-awaited product. If the website has been usually having traffic of 500-600 visitors, the website is unlikely to have sufficient resources to handle a sudden jump to 2000-5000 visitors.

With server load balancing, the load will be distributed across servers, making your website scalable without collapsing under the burden on the increased traffic.

  • Uninterrupted uptime: Whether these is need for turning a server off for maintenance, or these some kind of server failover, clients connected to that server will experience that the “website is down.” This leads to disappointment among customers as well as business loss.

A load balancer will automatically direct traffic from said server to the other serves that are running, so users never have to experience website outage or downtime.

  • Minimizing latency: During the periods of usual business, there may not be need to employ all the servers available. But when traffic increases, or the active server fails, there is need to call additional servers into action. The load balancer recognizes active servers and directs all traffic to them. When an additional server starts spinning, this too is recognized by the load balancer, which then distributes requests. In this manner, the load balancer adapts to auto scaling and minimizes website latency through load distribution.

In times of 4G internet, a time lag is loss of income, so a load balancer actually helps improve the bottom line.

What are the algorithms behind server load balancing?

Now that we’ve established the need for and significance of load balancing, let’s look at how it is carried out.

How does the load balancer figure out how to distribute the load? To which server should how much of the traffic be directed? Will the load balancer upset the balance and reroute too much or too little traffic to a particular server?

There’s a simple solution to work around these—algorithms that form the basis of load balancing.

1. Round robin: A simple enough formula, as per round robin algorithm for load balancing, client requests are handed out turn by turn in sequence to each server listed. Upon reaching the end of the list, the pattern is repeated from the first server.

This is easy to implement, and has further variations to ensure equitable distribution.

2. Least connections: This algorithm distributes client requests on the basis of the concurrent connections with the server. For instance, a new request will go to the server that has lesser connections at that moment in order to distribute the load.

This method is suitable for websites where user have longer sessions.

3. Source IP hash: This algorithm takes into account the source IP address of the client. A unique hash key is created for each source IP and the request is distributed using this hash key.

With this method, in case of a broken connection, the client request is directed to the same server when the connection is reestablished.

A specific algorithm is chosen as per the unique requirements of different e-commerce businesses, and the availability of resources.

What are the possible risks of load balancing?

To say it as concisely as possible, practically none! Load balancing itself is a risk management and reduction tool, and with the introduction of Amazon’s load balancer, backup systems kick into place seamlessly if the load balancer itself fails.

Is load balancing costly?

Compared to investment made on servers, the cost of load balancing is much lesser, and is worth the potential returns it offers. The now widely-used Amazon Web Services is much more affordable than configured load balancers, which were the norm earlier.

We hope we have covered all the questions you may have had about load balancing, and answered them clearly. As an ecommerce website monitoring and IT support company, we at Embitel Technologies definitely recommend using a load balancer to take traffic woes off your mind.