Hoping to simplify the ornery task of load balancing Microsoft Exchange servers, Kemp Technologies has released a virtual machine-based version of its Exchange 2010 application delivery controller, called Virtual LoadMaster Exchange (VLM-Exchange).
VLM-Exchange could be valuable to organizations that are finding their needs growing beyond what a single Exchange Server can handle, said Peter Melerud, Kemp vice president of product management. It would allow the organization to set up a second server to help handle the traffic.
VLM-Exchange could also play a role in increasing the availability of the Exchange service by allowing an organization to set up redundant servers that can handle traffic should the primary servers fail. And this virtual appliance addresses a configuration problem faced by administrators upgrading to the latest version of Exchange, Exchange 2010, which doesn't allow Microsoft's internal load balancer and the company's clustering technology to be used on the same server.
This new version Kemp's technology was first released as an appliance a month ago as LoadMaster-Exchange for Microsoft Exchange 2010. LoadMaster-Exchange is a version of the Kemp's general purpose load balancer, Loadmaster 2200, that has been configured for Exchange.
The package is pre-configured for a number of virtual services: one handling client access based on RPC (Remote Procedure Call), one for setting up a hub and edge configuration for SMTP (Simple Mail Transfer Protocol), and one for running Web-based services such as Outlook Web Access, Outlook Anywhere and ActiveSync.
VLM-Exchange runs in a Hyper-V virtual machine, which should be ideal for organizations that already deploy Exchange or other software within Hyper-V virtualized environments.
"Exchange works very well in Hyper-V hypervisors, so there will be a significant number of [our] customers deploying Exchange on top of Hyper-V," Melerud said. "Companies can just create another virtual machine within their Hyper-V environments."
This version also addresses a new problem that administrators may face when upgrading to Exchange 2010, one encountered if they run multiple Exchange servers as a single instance, with some sort of load balancing evenly distributing work to each of the machines. For the first time with Exchange, administrators cannot run the Microsoft Windows Server own internal load balancer functionality, called the Network Load Balancing (NLB), and the Microsoft clustering technology on the same server. This change is problematic for organizations that need the clustering technology to manage multiple Exchange servers as a single service.
"In prior earlier versions of Exchange, you didn't have to have an external load balancer. You could have used NLB. In Exchange 2010, you must have an external load balancing appliance," Melerud said.
Microsoft, which verified Melerud's description of how Exchange 2010 works, suggests either running each Exchange service on a separate server, or running an external load balancer, such as Kemp's. Melerud argues for using a virtual machine-based load balancer as it eliminates the cost for paying for separate server and associated software licenses. It also cuts the labor costs of configuration.
"It's very difficult to get Microsoft load balancing working. So you really need some type of external load balancer in front," agreed Ben Serebin, who organizes the New York Microsoft Exchange Server User Group (NYExUG), to whom Kemp technologies gave a presentation of the technology in March.
Serebin has tested Kemp's software, and found it relatively easy to use and set up. The company endeavored to make the Web management and administrative interface easy to use, and intuitive for administrators unskilled in the ways of load balancing. "There is definitely some configuration but Kemp has made it very easy to deploy the solution," he said.
Kemp launched this product at the Microsoft Tech Ed conference, being held this week in Atlanta. VLM-Exchange costs US$2,990.00.