Server load balancing doesn’t sound the most exciting or sexy IT topic for discussion, but bear with me. Until recently, load balancing was something only large enterprises needed to worry about; viewed as nothing more than a costly and unnecessary expense for most SMEs.
But that was back when the Internet was emerging and most SMEs ran their businesses using just a couple of servers. Today, the number of servers used by SMEs has multiplied, while at the same time web traffic has grown exponentially, putting a strain on networks and resources.
So what is load balancing? In effect, load balancers are like the traffic police; they keeping the traffic moving by directing and sharing internal network traffic and incoming connections across multiple servers.
A load balancer solution allows you to plan for handling increased web or network traffic by ensuring that it is directed to servers that are performing best and have spare capacity, based on factors such as concurrent connections and CPU/memory utilisation. And if a server or application fails, the user is automatically re-routed to another functioning server, providing a seamless experience for the user.
This growth in traffic that is driving the need for load balancing is in part the result of more back-end applications, such as sales and order processing, customer relationship management, HR and billing.
These are critical business applications where reliability, scalability and performance are essential. Furthermore, a server that keeps timing-out because it can’t cope with the level of Internet visitors and e-commerce transactions will not help your sales, image or reputation.
To further enhance and secure the user experience, particularly for transaction-based web services, some load balancers also enable processor-intensive encryption/decryption processes to be removed from the servers. This offloading dramatically increases web server performance, while decreasing the time and costs associated secure e-commerce.
The Microsoft Factor
Microsoft also has a hand in driving the demand for server load balancing as SMEs migrate to Exchange 2010 email services. The list of changes Microsoft has made to its core server architecture in Exchange 2010 includes the use of Exchange Client Access Server (CAS) to handle client connections. This makes load balancing necessary to automatically re-route and reconnect users to optimised servers to avoid poor performance and deliver high availability.
For example, when Hyundai UK decided it was time to retire its old Lotus Notes platform and migrate to the new Microsoft Exchange 2010 solution, it had to be a smooth transition and deliver a fast, reliable and resilient service. The new Exchange system supports 200 users split between four sites as well as the remote Field Team that looks after the Hyundai dealership network.
To run the new Microsoft Exchange 2010 platform, the Hyundai IT team built two virtual Exchange servers based on VMWare and installed a KEMP LoadMaster hardware load balancer – Microsoft Certified for use with Exchange 2010 – to ensure that email users get the best experience and optimised performance.
Hyundai configured the new email service and shut down its old Notes system on a Friday evening and had Exchange up and running for Monday morning with no loss of email. In addition to providing load balancing between the two virtual servers, the load balancer also provides built-in SSL acceleration. “Load balancing is a core part of our Exchange 2010 solution now and into the future as the business in the UK continues to expand,” said OJ Chakrabarti, systems & infrastructure manager, Hyundai UK.
But as well as the migration to Exchange 2010, many SMEs adopting Microsoft SharePoint and Lync Server unified messaging technologies are discovering the need for load balancing. For example,
Lync has to support real-time VOIP traffic flows that are jitter- and latency-sensitive. In fact, Microsoft increasingly recommends the use of server load balancing to optimise performance and resilience of all these applications.
The complexity and scale of technology required to run today’s SMEs has brought with it many new challenges to deliver performance, high availability and security, but cost is always a key factor. While large enterprise load balancing solutions have been too expensive and complex for most SMEs, there is a new generation of affordable hardware or virtual load balancers aimed at this market. SME IT is the same as enterprise IT in everything except scale; and if SMEs want the functionality and quality that enterprise CIOs take for granted, load balancing has to be part of the equation.
