Windows Server users frequently seek to improve performance using load balancing — a technology that can enhance speed, reliability, and user experience, among other factors. But what is load balancing, exactly? And how does it work to bring about these performance enhancements?
What is Load Balancing?
Load balancers come in a number of different forms, from hardware load balancers, to software load balancers and cloud-based LBs too. Despite the different types, these load balancers all work in the same basic manner: a central hub server is placed to intercept the incoming client requests before they are transferred to a server pool or server cluster. If large batches of incoming requests were permitted to pass along to a server without being intercepted, there is a good possibility that they would overload the server, resulting in major slowdowns and even crashes, resulting in downtime and other adverse consequences. For this reason, it is preferable to use a load balancer to intercept and distribute server requests across multiple servers in a pool.
Once the server requests arrive at the load balancer server hub, the server requests are evaluated according to a load balancing algorithm. The algorithm is used to determine how the server request will be handled as it is sent along to the server cluster. Each type of load balancer has the capability to evaluate these server requests in slightly different ways which is a key reason why there is no one-size-fits-all load balancing solution.
The load balancer’s hub server also performs health checks on the servers, effectively minimizing the number of server errors that are generated. The end result is a better user experience and better overall efficiency since you are far less likely to encounter those bothersome errors. What’s more, by performing health checks, you reduce the risk of server crashes since unhealthy servers can be detected with relative ease and then flagged for maintenance and repairs.
How Do You Load Balance a Windows Server?
There are a few options for load balancing in a Windows Server environment. You can use a network load balancer (NLB) or a software load balancer (SLB) in conjunction with Windows Server 16, among other versions.
Notably, Windows Server 2016 features an “Azure-inspired” software load balancer as part of its software-defined networking (SDN) infrastructure. This in-built Windows Server software load balancer is recommended for cases where you have non-Windows workloads or cases involving non-TCP-based load balancing needs. Software load balancers are also suitable for use in cases where you need to perform layer 3 load balancing or outbound network address translation (NAT).
In the case of deployments that do not use software-defined networking (SDN), it is possible to use Windows Server 2016 in conjunction with a network load balancer (NLB). Network load balancers work by distributing incoming server requests across multiple servers in a server pool. NLBs leverage TCP/IP networking protocol as the basis for their evaluation of incoming requests.
According to Microsoft, “By combining two or more computers that are running applications into a single virtual cluster, NLB provides reliability and performance for web servers and other mission-critical servers.”
Network load balancers can be configured to accommodate increased server demand, which is ideal for Windows Server 16 users who require a scalable solution. Network administrators can add hosts — a term for servers in the server cluster that handles the incoming requests — as needed. All that is required is a bit of configuration to determine how much load each server in the cluster will handle.
Network load balancers can also be configured to use a single IP address set for the computers within the cluster, with a dedicated IP address assigned to each server in the server pool. If one of the servers goes offline, its load will be distributed to the other servers until it is repaired. Once the “unhealthy” server returns to the cluster after servicing, incoming requests are automatically dispatched to the host, allowing for a smooth transition and reducing the load on its fellow pool servers.
Benefits of Load Balancing in a Windows Server
There are many advantages of implementing load balancing in a Windows Server. This is especially true for those who opt to use a network load balancer with Windows Server 16 platforms.
High availability is one significant advantage. A load balancing configuration with high availability means that the servers are not overburdened and they are continually available to take on incoming server requests without the risk of downtime (or minimal downtime.)
Thanks to their configuration, network load balancers very frequently have high availability. They can use health checks to detect when a server in the pool gets overwhelmed and experiences downtime, subsequently signaling a network administrator that it requires servicing. Network load balancers can also rapidly redistribute workload to ensure even burden on all servers in a cluster.
Additionally, network load balancers for Windows Server allow for great scalability. Network administrators have the ability to add servers to the cluster as needed when using this load balancing configuration. In the case of Windows Server load balancing, you can add up to 32 hosts in a single server cluster on an as-needed basis, using them to balance for numerous individual TCP/IP services. It is also possible to remove servers from the server cluster if demand decreases.
Pipelining is also possible with a Windows Server network load balancer. This works by sending incoming server requests to the server pool before you’ve received a response to a prior request. This speeds the process and allows for “high performance and low overhead.”
Load balancing Windows Server can require a bit of expertise in networking and load balancing technology and in some cases, a third-party solution may be the ideal option. This is where Resonate can help since we offer a variety of load balancing technologies for clients using Windows Server and a wide array of other platforms and interfaces. Resonate specializes in reliable, scalable, cost-effective high-performance load balancers. We invite you to contact the team at Resonate to get started finding the best load balancer for Windows Server 16 and other platforms. We look forward to discussing your load balancing needs.