Terminal Server Load Balancing | Parallels Blog

Automatic Terminal Server Load Balancing

Windows Remote Desktop Services (RDS) enables businesses to publish resources to remote users so that Windows applications can be accessed from a range of devices and from any location. With Microsoft taking terminal servers mainstream through the introduction of the Windows Server OS, most businesses are now able to configure the server OS to create remote networks. However, load balancing becomes an issue when there are multiple servers involved, as it can be difficult to assign a user to a particular server. This is where “terminal server load balancing” comes to the rescue. Using the load balancing option, you can transparently distribute incoming remote connections to available servers with ease.

Terminal Server Load BalancingFor businesses, there are two options for terminal server load balancing. With  the release of Windows Server 2003, Microsoft began offering a component called Network Load Balancing (NLB). NLB works with any client and checks for servers that are available to take new connections. However, it is not resource-based and is limited to 32 servers which have to be on the same subnet. Another limitation is the reconnection issue. Once a connection is dropped, it might not be reconnected to the same server.

To address the reconnection issue, Microsoft offers another component called the Session Directory. NLB with Session Directory is available with Windows Server 2003 and later versions. This session directory maintains a database that records the details of users connected to each terminal server. When a connection is dropped and is requested again, the session directory checks this database and assigns the same terminal server to that particular user, if available. However, Session Directory is not resource-based; it only checks for the number of connections.

The second option for terminal server load balancing is to use a hardware appliance from Cisco, Foundry Networks, or F5 Networks. However, while these hardware appliances work intelligently, installing redundant hardware solutions for terminal servers can run your budget into tens of thousands of dollars.Terminal Server Load Balancing

Parallels Remote Application Server offers load balancing out of the box

Parallels Remote Application Server offers an easy and cost-effective way to perform terminal server load balancing. In fact, you don’t have to do anything extra because High Availability Load Balancing (HALB) is included with Parallels Remote Application Server; there is no need to install and configure multiple components. Parallels Remote Application Server is a comprehensive package that comes with advanced features packed into a single entity. With a single virtualization tool, you can remotely publish virtual desktops and applications and manage and monitor them from a centralized dashboard. It supports all major hypervisors, browsers, and operating systems. You can leverage the Windows Server OS to cost-effectively run remote networks. Windows applications can be published to a range of devices with ease. Most importantly, Parallels Remote Application Server is inexpensive.


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