Uninterrupted operation of IT systems is the goal of any data center manager. A data center facility is only as valuable as its functionality. In today’s modern world, we rely on data centers to process huge amounts of data for business, banking, and governments. Environmental parameters influence the ability of IT hardware to function. Factors such as power supplies, cooling units, and even colocation providers are some of the variables to consider. It is critical to select a data center provider that offers redundant backup systems. But how critical is N-Modular redundancy?
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Improve the fault tolerance of IT facility
Introducing N-Modular Redundancy

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There are different levels of redundancy. But N-modular redundancy is the most basic term we refer to when making duplicate units to our IT system. The levels are as follows:
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N
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N + 1, N + 2
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2N, 2N + 1, 2N + 2
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3N/2
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N Redundancy
The N stands for the baseline number of the existing IT units. For example, N IT servers are running in the data center. In essence, it is the bare minimum number of IT components necessary to run the system.There are two significant characteristics in N-redundancy-
No redundancy is present in the existing system
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Because no redundancy is available, there is no backup solution when failure happens
In principle, the system is shut off until the issue is checked and resolved. As such, it is not recommended for many IT systems to operate under the N redundant premise. Moving forward, this level should be the benchmark point to bring in higher redundancy levels to one’s IT system. -
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N + 1, N + 2 Redundancy
In the premise of N + 1 redundancy, a single backup is added to the current number of IT units. This is the prerequisite in introducing redundant IT components. At this level, that single backup is available anytime a particular part breaks down. The system can operate as usual. This kind of setup is feasible for small IT systems.In the N + 2 setting, two separate backups are made available for the system. While the system operates following the baseline unit constitution, two independent backups can solidify its uptime. This is essential during IT failures. Other than one backup, there is another one that can compensate for the task. This redundancy is helpful if the other backup unit is corrupted.There are also other instances that data managers will prefer more than two separate backups. This is referred to as N + X. The X pertains to any number of backups that are deemed necessary for the system to maintain uptime. -
2N, 2N + 1, 2N + 2 Redundancy
Because we refer to N as the baseline number of resources to run an IT system, 2N is twice the baseline capacity. If you are running five servers in a data center under the premise of 2N redundancy, you need an additional five servers as backup. This accounts for ten servers to run the 2N redundant IT facility.The 2N redundant setting mirrors the existing number of capacities an IT system has. When the existing servers undergo downtime, the exact number of backup servers can cover for it.To further ensure IT capabilities, 2N + 1 is incorporated. Such redundancy level signifies that there is twice the required capacity of the unit plus one backup. The same premise follows the 2N + 2 system. There is twice the required IT capacity plus two separate backups. This type of N-modular redundancy assures the highest level of redundancy it can provide in the IT system. Simply put, if you have five baseline servers, there are five more as backup, then two more as another backup layer on emergency cases. -
3N/2, 4N/3 Redundancy
The Vital Premise of Redundancy
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In low failure rates of individual components, a basic redundancy policy is needed to provide high availability
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Complex redundancy protocols are required in components with higher failure rates
Choosing the Suitable Redundancy Configurations
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Active
The active configuration follows that original and redundant component operates together. In a simultaneous run, both components will power the IT facility. In the case where the original unit breaks down, the redundant part will be utilized.
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Passive
The passive configuration saves the redundant component in time when the original one fails. In essence, the original component is operation up until it breaks down. This is where the redundant component will fulfill its function. -
Load Sharing
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User and system requirements
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Unit and/or component costs
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Available resources
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Standard compliance requirements
Streamlining N-Modular Redundancy to Achieve Comprehensive IT System

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