Server clustering is a technique of utilizing multiple servers to gain technological advantages not possible with just a single of very few servers.
At Sagacent Technologies we strategically use server clustering to help a business gain:
- High-Availability – adding redundancy to the network to reduce or single points of failure and offer far greater resiliency, business continuity and fault tolerance.
- Load-Balancing – sharing a workload across more than one device in order to offer superior performance.
While server clustering was previously limited to large and enterprise-sized companies, happily, it is now more affordable than ever and making its way into even small and mid-sized businesses where performance or fault tolerance is crucial.
Server Clustering Basics
Server clustering allows a group of servers to work together on one system to provide users with higher availability and reliability. Clustering also allows for scalability of the systems, meaning your server needs can seamlessly grow along with your business.
By working together, server clusters reduce downtime and outages by letting one server take over when another is unavailable. When a business has only one or two servers available, there is little opportunity for redundancy. This means that when one of them is down, your whole system is down, or your capabilities are halved.
When servers are clustered, there is much more redundancy. The moment one of the servers in the cluster experiences an outage, the workload is redistributed without interrupting work currently in progress by any of the users.
How does server clustering work?
In these clusters, each server is responsible for each of the devices operating on it, but each also has a copy of the operating system as well as any applications or services being used to run the other servers in the cluster. This allows the servers to work together to enhance the security of the data and maintain consistent configuration across the cluster.
Server clustering protects against three different types of outages, including:
- System or Hardware Failure: These outages generally impact components such as central processing units (CPUs), adapters, memory, power supplies, and drives.
- Application or Service Failure: This type of outage impacts applications and services on the network that are critical to its operation.
- Site Failure: These outages generally stem from things like natural disasters or when there is a widespread power outage. Site failures may impact multiple locations.
Additional Benefits of Server Clustering
While the high-availability and load-balancing capabilities of server clustering are generally the top-cited benefits, server clustering offers many additional enhancements.
- Capacity on Demand: Capacity on Demand (CoD) is a type of horizontal scalability that allows servers to meet peak demand when necessary. CoD ensures that the clustering technology is able to allocate resources nimbly and know when those resources can be reassigned based upon workload changes. This process is done without impacting performance and without users even noticing the changes.
- Parallel Processing: For tasks that are a bit more intensive, server clusters deliver low-cost parallel processing. This allows the program instructions to be divided among multiple processors, reducing the total time necessary to complete the program.
- Systems Management: Clustering can make server administration much easier. Rather than managing multiple disparate servers, you can manage a cluster as a single system. Many features, such as intuitive management and administration, failure detection and recovery, as well as the ability to add and delete resources without interruption, make this process easier than ever before.
- Scalability: Given recent trends in computing, scalability has become more important than ever. You need to ensure that you are able to grow at the optimal rate for your business without impacting performance. Server clustering is in line with completing this task seamlessly, as it can accommodate peak demand by load-balancing, and server capabilities can continue to increase as needed.