Microsoft Exchange Server 2010 continued the architectural changes begun in Exchange 2007—specifically, moving basically all client access to the Client Access server. This change provides a smooth, consistent flow of data through the organization, and makes for simpler failover scenarios. It also facilitates—or, indeed, necessitates—load-balancing of the Client Access and other Exchange server roles.
I recently spoke with Peter Melerud, vice president and co-founder of KEMP Technologies, makers of load-balancing products aimed primarily at the small-to-midsized business (SMB) market. In speaking about the architectural changes to the latest Exchange version, Melerud said, "That's really what created almost a requirement for having a load balancer that was smart enough to handle the various Exchange 2010 roles."
The KEMP LoadMaster is available as an appliance that you can slot easily into your existing Exchange environment. KEMP also offers a software version, Virtual LoadMaster (VLM) for Hyper-V; both of these products have been approved by Microsoft's qualification program for load balancers for Exchange Server 2010.
KEMP makes load-balancing products that work with other Microsoft technologies as well, so Melerud naturally had much to say about the importance and usefulness of a good load balancer: "You may have a server that's up and running with a fully loaded IP stack, but the application itself is hung. So load balancers have some sophisticated capabilities where they can do health checking on pretty granular levels on various applications, including Exchange for example. They can look at the server health; they can look at performance, CPU utilizations, I/O speeds, memory utilizations, temperatures even, to determine which server should get the next request."
With a price-point starting at $1,490, KEMP is committed to serving the SMB market, making full-featured load-balancing possible for almost any organization. As Paul Robichaux wrote in his recent commentary, appliances "are essentially single-purpose servers that you install to provide a specific function on your network. . . the basic idea is to deliver a service that requires a minimum of effort from the system administrator." With that in mind, taking a look at KEMP's products for Exchange load-balancing might make a good deal of sense.