How Critical is N-Modular Redundancy in an IT System?

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N-Modular Redundancy

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?

Dependable IT is a competitive edge to business operations. Ensuring that the IT facility is reliable equates to better business opportunities. At the same time, it cuts the risks from unforeseen events.
One way to negate risks is to build a dependable IT system through redundancy. This integrated activity can help in:
In principle, integrating redundancy to the whole IT system is to add duplicate or redundant units to cover specific tasks. In the event of a primary system failure, the redundant systems will take the place of the primary, ensuring continued operation.

Introducing N-Modular Redundancy

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:

  • N
  • N + 1, N + 2
  • 2N, 2N + 1, 2N + 2
  • 3N/2
  1. 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
    • 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.
  2. 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.
  3. 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.
  4. 3N/2, 4N/3 Redundancy
The 3N/2 and 4N/3 redundancy level is derived from a baseload of the IT system. This is a redundant method where capacity is divided to ensure that the proper allocation is given to the system. Take, for instance, a power supply system to your IT facility.
In a 3N/2 level, there will be three individual power supply systems to stream two servers. Such a scenario results in allocating only about half of the available capacity at a given time. With regards to 4N/3 redundancy, four power supply system is involved. This number of power units is utilized to power three servers. The result uses only 75% of the available capacity.

The Vital Premise of Redundancy

The N-modular redundancy integration can provide deeper reliability and availability of your IT system. Using redundant methodologies, an IT system is bound to carry on with the operation. The risks of downtime due to failure and maintenance are avoided as redundancy provides backup solutions.
One vital consideration in integrating a redundancy method is the failure rate of individual components. As such, particular action steps are necessary to address this variable:
  • In low failure rates of individual components, a basic redundancy policy is needed to provide high availability
  • Complex redundancy protocols are required in components with higher failure rates
Another variable for consideration in planning redundancy methods is system workload. Redundancy levels can refer to the amount of workload in the system. The higher system workload is consequently prone to stress which leads to faster component breakdown.
Despite the many benefits of redundancy, it is essential to note the disadvantages of this setting. Backups should match the existing components in an IT system. A mismatched spare component will only lead to performance fluctuations. Backup’s specifications should be very close to the existing ones, as capacity is affected. In the long run, the impact on the IT system may be more detrimental than beneficial.

Choosing the Suitable Redundancy Configurations

In any redundancy method, be it an N-modular redundancy, there are respective configurations to choose from. These configurations will take precedent when implementing your desired redundancy method.
  1. 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.

  2. 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.
  3. Load Sharing

In this type of configuration, both original and redundant component is operational but not in full capacity. There is a partial allocation of working load to compensate for the availability gap of the original component.
Integrating these configurations into your IT system will have many considerations as a prerequisite. Even implementing the N-modular redundancy will have to befit to the following operational indicators:
  • User and system requirements
  • Unit and/or component costs
  • Available resources
  • Standard compliance requirements

Streamlining N-Modular Redundancy to Achieve Comprehensive IT System

N-Modular Redundancy

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As critical are redundancy to any IT system, much of the operational process is given to maintaining these essential components at tiptop shape. Their reliability will be fully utilized if these redundant components will be monitored regularly.
There are monitoring solutions that are well equipped to track individual components of an IT system. Some monitoring technologies also have a comprehensive tracking capacity for an entire IT facility.
The AKCP monitoring system has a long line of customized and comprehensive monitoring technologies. These consist of power, environmental, security, access monitoring. With the AKCP wireless sensors, remote monitoring is hastened. Real-time alerts are generated to allow a quick response.
In a redundant IT system, AKCP provides solutions that is well specified for any application. AKCP has intelligent base units that can connect to AKCPro server. The server acts as a central management software enabling the real-time and regular monitoring of all IT components.
Granular visibility on the conditions of redundant components is also easy access through the relay from the deployed sensors to that of the IT.
With added IT infrastructure, comprehensive monitoring tools will enable full tracking of all IT components. Providing ease to the monitoring activities ensures that redundancy integration is working at optimum condition. Through these monitoring endeavors, unforeseen issues are detected early. This will lead to quicker action steps negating the risks of system downtime.

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AKCPHow Critical is N-Modular Redundancy in an IT System?