Data Center Redundancy: What It Really Means and Why It Matters

neuCentrIX - 30/12/2021 19:00

When choosing a data center, organizations must evaluate various factors. One of the most important aspects of a data center’s infrastructure and capabilities is redundancy. 

In the IT field, redundancy essentially means duplication. It refers to a practice of ensuring that a system includes a backup — either a component or full-system backup. When it comes to data centers, redundancy is usually required for power and cooling components because they’re vital for maintaining system health, reliability, and accessibility.

Why is data center redundancy important?

It is data centers’ responsibility to ensure data and services are available to customers whenever they’re needed. If these data and services aren’t accessible, the operations and productivity of businesses that rely on them will be affected. The objective of redundancy is to ensure the systems in a data center keep running and data stays available despite any issue.

Component failure is a major problem for data centers. Many parts of the systems in a data center can fail due to various issues, including attacks, poor programming, and natural disasters. With redundancy, data centers can immediately replace a failed system with a working one. It also allows customers to remain operable while giving providers time to determine the cause of the failure and how to troubleshoot it.

However, redundancy doesn’t only help when dealing with system failure. When considering the need to scale for business growth, redundancy also ensures that there is no downtime during new components installation.

What are the levels of data center redundancy?

Let’s start with the symbol “N”. N represents the infrastructure needed to keep a data center running at full capacity under a specific workload. In the context of data center practices, N usually refers to the cooling capacity and uninterrupted power supplies as mentioned before. 

There are four redundancy levels which are measured in N ratings.

Obviously, N represents baseline capacity. A data center with N redundancy has everything it needs to operate as designed but has no redundancies in place to accommodate component failure, maintenance, or upgrades.

The industry standard for minimum redundancy is N+1. N+1 redundancy means that a data center has the capacity needed to run a full load with an additional component to account for failure or maintenance. This redundancy level assures that for every four components in use at a data center, there is one extra unit. For example, if 12 cooling units are required, a facility with N+1 redundancy would have 15 units.

Some data centers apply N+2 redundancy. The principle is similar to N+1, but N+2 means two extra units for every four components used.

2N redundancy means that a data center is totally redundant. It has a completely independent, mirrored system, with a duplicate unit available for every component in use, which can fully take over operational needs if the first system goes offline. A data center with 2N redundancy is considered fault-tolerant as they can provide uninterrupted service even when the whole system fails. That’s why this is the minimum level of redundancy for organizations which require near-complete reliability (hospitals, police departments, etc.)

It’s the highest level of data center redundancy. 2N+1 redundancy means a data center has a duplicate unit for each component used, with an extra unit for every four components. As it has full, fault-tolerant redundancy, a data center with 2N+1 capacity provides high-level versatility and reliability. In fact, most data centers with this redundancy guarantee periods of downtime that last no longer than 26 minutes per year.

Once you understand how important data center redundancy really is and know that you can choose from four redundancy levels, it’s time to choose a provider that can meet your requirements. neuCentrIX’s data centers offer you minimum N+1 redundancy, making us a great option for your data center needs.