StorageWhat Is Scale-Out NAS? Pros and Cons

What Is Scale-Out NAS? Pros and Cons

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To handle the performance needs of the workloads of today, a storage architecture needs to offer flexibility, agility, and efficiency. As such, scale-out network-attached storage (NAS) is a cost-effective architecture that handles these workloads and can keep up with the growth of structured and unstructured data to meet the data storage requirements of today.

Read more: Best Enterprise-Grade NAS Solutions

Scale-Out NAS vs Traditional NAS

Traditional NAS, also referred to as scale-up NAS, involves using a scale-up approach when adding resources such as storage and memory to existing hardware. Devices in scale-up NAS configurations can hold hundreds of terabytes of data, making it an attractive solution for the storage needs of SMBs (small and medium businesses).

The resources you can add to a scale-up storage infrastructure are dependent on the physical capabilities of the NAS hardware. These capabilities determine how much resource addition a NAS device can handle. When the resource demands exceed the available hardware, new hardware is required, as adding capacity ceases to be an option. This however introduces the risk of server sprawl.

Read more on TechRepublic: 5 Tips to Protect Your NAS From Cybercriminals

Furthermore, considering the possibility of having hundreds of devices, the power, cooling, and space requirements make storage management cumbersome, potentially making scale-up NAS complex and cost-prohibitive. It also faces the challenge of anticipating future capacity requirements.

Additionally, where unstructured data demands are concerned, a scale-out approach is more popular. As both performance and capacity can be upgraded, scale-out network-attached storage provides a natural alternative to the challenges of scale-up storage systems.

It offers the flexibility required to adjust to varying business needs, control complexity and costs, and optimize resources. Scale-out NAS provides a scalable answer to the ever-increasing volumes of data enterprises struggle to manage, without introducing additional strain on existing IT resources.

While scale-out storage systems form a clustered storage array through a group of servers and offer logical unit numbers or file shares over a network, the performance of a scale-out array increases with an increase in its capacity. The architecture does not need downtime to add capacity and performance to the array as the process of adding nodes is not disruptive.

Read more: What Is NAS Software and How Does It Work?

How Scalable Is Scale-Out NAS?

The controllers of scale-up NAS systems have a predefined number of disk slots as well as memory and CPU resources. As a result, scale-up NAS performance tends to degrade with an increase in storage units, as the control function fails to increase with an increase in capacity.

Scale-out network-attached storage enjoys unparalleled capacity since its controllers can link multiple entities to ensure they function as one logical unit. This enables the whole system to be managed simultaneously. Thus, the scale-out system scales linearly, as a doubling in resources leads to a double the performance, with no diminishing returns during scaling.

Scaling in the absence of degradation makes it easy for scale-out NAS to handle vast amounts of data. It also enables scale-out NAS to easily handle demand surges, as it is simpler to add capacity without having to move any data, in comparison to scale-up approaches where greater capacity hardware would be required to accommodate data growth.

Read more: Scale Up vs Scale Out: Data Center Infrastructure

Benefits of Scale-Out NAS


Scaling out storage offers the freedom to improve and lower capacity and performance as the storage solution is based on client needs. Flexibility enables scale-out NAS to handle today’s high volume of unstructured data and satisfies the flexibility demands of a big data environment.

Data Center Usage

Unlike traditional NAS, scale-out network-attached storage saves data center space and satisfies the need for expensive additions. The complexities of scale-up storage in the form of management challenges, physical constraints, and potential server sprawl are addressed by the constant scalability offered by scale-out NAS.


An effective scale-out NAS solution goes beyond the restrictions of traditional hard drives to provide users with the most value from their storage capacity. It also improves overall organizational efficiency as organizations can focus on managing data and reduce focus on managing storage. An efficient system yields lower capacity needs for data storage.


Scale-out NAS offers visibility that allows every connected node to see every stored file across a cluster. This helps manage clusters as a consolidated storage system, and through dynamic resource allocation, capacity and performance can be added, minus management challenges. Visibility also helps prevent downtime, as a load can be distributed across a cluster in the event of the failure of a node.


Investing in scale-out NAS hardware is cost-effective, as it eliminates the need to make long-term expansion considerations. Additionally, scale-out NAS results in lower data center space requirements and energy and management costs along with a flexible on-demand model.

Read more: Best Free and Open Source NAS Solutions

Challenges of Scale-Out NAS

While scale-out network-attached storage comes with a multitude of benefits, there are still a few drawbacks to consider when determining whether or not to deploy this architecture.

  • Deployment Cost: Although cost-effective in the long run, scale-out NAS is often more expensive to deploy than traditional NAS.
  • Licensing Fees: The licensing fees involving adding proprietary hardware and software may be an obstacle to enterprises seeking to deploy these solutions.
  • Network Connectivity Requirement: Scaling out requires greater connectivity, as it is network-dependent.

Gaining the Benefits of Scale-Out NAS

A scale-out network-attached storage system is clearly an improvement upon scale-up NAS, especially where unstructured data is involved. However, to realize the benefits of scale-out NAS, as well as maximum cost-effectiveness, you should ensure the solution is simple, efficient, available, and flexible.

Read next: Best ETL Tools: Extract Transform & Load Software

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