NAS Buyers Guide

NAS Processors

The CPU is the brain of the NAS, controlling how data is written to the drives and the speed at which it can be retrieved. Normally if you are buying a PC for home or work, you are buying it based on its ability to do tasks as quickly as possible. However, a NAS will often be on for days, weeks or months at a time, unlike your desktop PC. Plus, most of the tasks it performs are passive or require much less CPU power. The result is that the CPU found in most NAS appears to be rather modest when compared to the desktop computer alternatives, as the CPU needs to be more efficient about power consumption and heat. Because of these differences from PCs the CPUs seen in entry-level and mid-range NAS boxes are often Arm based such as Marvell, Annapurna or Realtek - alternatively they may be the less powerful Intel x86 models such as Intel Atom or Celeron. These are all perfectly adequate to perform basic NAS features, although if you intend heavier usage of applications then consider a NAX box with a quad-core CPU rather than a dual-core CPU. Although it is difficult to guarantee a performance level due to factors such as the number of users and network speed the following pointers offer some insight as to how to best choose a NAS depending on it’s CPU.

Advantages of low-cost CPUs:

• Low cost of CPU means that the overall cost of NAS is lower
• Low spec CPUs consume less power helping to reduce running cost
• Low cost CPUs are still powerful enough to handle DLNA Media streaming, typical file level exchanges and backups
• Can support surveillance based NAS use and multiple IP cameras but will see limitations as numbers increase

Disadvantages of low-cost CPUs:

• Will struggle if many users are connecting concurrently
• Cannot handle transcoding, large-scale rendering or 4K media
• Higher-end software features will not be able to run on low-cost CPUs

It is worth mentioning that there are high-end NAS boxes with AMD Ryzen, Intel Core and even Intel Xeon CPUs which are squarely aimed at the business and enterprise markets where large data sizes are the norm and fast connectivity is required.

Memory

The amount of memory (or RAM) required in a NAS will largely depend on the applications and number of users accessing the NAS at any given time. It is generally a rule of thumb that if your NAS is going to be used by more than five people and for backups and multimedia, then you should have at least 2GB of memory to ensure completely fluid activity. It is recommended to go for at least 4GB if you are using RAID. If, however, you are going to use a NAS for business, large-scale surveillance with multiple IP cameras for CCTV, or to run multiple virtual machines (VMs) for users to have their own bespoke virtual desktop, then you will need to start with at least 8GB of memory. It is worth bearing in mind that large rackmount NAS devices are essentially storage servers so they scale in RAM as a server - up to 512GB.

In many cases, it is possible to expand the memory in NAS device, just like a PC or workstation, so you should look out for this ability if you intend for your NAS use to scale. All NAS manufacturers will provide a compatibility matrix to ensure you choose the correct RAM if deciding to upgrade - either by purchasing the branded memory or a compatible alternative.

Drive Bays

Although we’ve addressed CPU and RAM first, it is fair to say that the more drive bays a NAS box has then the specifications of the system will also increase in anticipation of heavier workloads, more users and more intensive applications. NAS boxes with at least two bays still offering basic RAID options to afford some data protection, and those scaling to 24 bays in a single rackmount chassis offering much greater RAID flexibility. The drive bays themselves are not that different regardless of which model you choose. Most will be covered with a banking plate when no drive is present, and when drives are in place they can be removed by flipping a small lever or clip at the front. The vast majority of NAS drive bays are hot-swappable - a feature that allows you to take out the drive and replace it with a new one (either after failure or for upgrade), without the need to power down the NAS. Although RAID settings are required to effectively use this feature, it does make maintaining your data very simple. If you want these features then avoid the entry-level NAS as they usually have fixed drives that you cannot access from the front of the box.

The majority of drive bays are 3.5in slots featuring SATA III connectors that will take either 3.5in or 2.5in HDDs or SSDs. Some NAS boxes also feature dedicated 2.5in drive bays aimed specifically at SSDs for advanced high speed caching. A more recent development is the inclusion of multiple M.2 SSD slots internally to enable tiered storage support in a single device being used for fast access and archive purposes.

Connectivity

NAS boxes include a variety of connections as standard, although the number and type will vary on whether it is an entry-level or a high-end model. The very minimum every NAS device will have is an RJ45 Ethernet network connection. This will usually be 1GbE. Ethernet is by far the most common network connectivity standard around and Gigabit speed connections are common on most desktop PC or workstations today. Some mid-range and high-end NAS boxes feature 10GbE offering 10x the performance when used with a 10GbE network throughout – useful if you are working with larger multimedia files rather than simple documents.

It is also common as NAS boxes increase in price and performance that multiple RJ45 Ethernet ports will be present, sometimes in mixed configurations such as 2x 1GbE and 2x 10GbE. This is designed to give options for connectivity and to provide link aggregations features, where two or more ports can be combined to give a greater throughput speed - 2x 10GbE = 20GbE. Alternatively, the different ports can be used for failover - redundancy in case one connection should fail. You may also see the following ports on a NAS box.

USB

A single or several USB ports may be provided. Any front mounted USB ports are usually for the direct upload of data from an external drive onto the NAS box, whereas any rear mounted ports are intended for connection to an external storage drive to back up the NAS.

eSATA

Some NAS boxes include an eSATA port so you can easily expand the total drive capacity.

Expansion Ports

We mentioned earlier that some NAS boxes can be expanded, but rather than using a third-party connection such as USB or eSATA, they come ready with one or more expansion ports in order to connect a second expansion chassis - usually almost identical to the original NAS unit but with no inbuilt intelligence. We’ll come back to these later.

Software

As we’ve touched on previously the basic functions of a NAS box are to store and share data, act as a backup and protect data. However, leading NAS brands such as Synology and QNAP have taken the feature set several steps further and enabled a whole host of additional functions. We’ll take a look at some of these but it’s always worth remembering the OS on most NAS devices will be the same, but some functions may be limited by the CPU and RAM available. If you know you want advanced functionality then purchasing a high-end NAS is the way to go. It’s also worth mentioning that the OSes are regularly updated, enabling you to take advantage of new features without the need to change hardware.

Management

Configure, maintain, and monitor every facet of your NAS - no IT professional required.

File Syncing

Sync your files securely between multiple computers, servers, and public clouds.

Data Backup

Protect personal data on VMware, Windows endpoints, and SaaS applications.

NAS Protection

Protect data on NAS against unexpected hardware failure, natural disasters, and accidental deletion.

Virtualisation

Provide a complete vitualization solution with Virtual Machine Manager.

Productivity

Boost productivity with Office and Drive, streamline projects with Chat, set up a private mail solution, and so much more.

Multimedia

Enjoy photos, videos, and music through an intuative web and mobile interface.

Data Security

Industry-leading security solutions defend your NAS from sophisticated threats.

Additional Software

As the points touch on above mid to high-end NAS devices are essentially small office servers and they can be used in this way providing email and productivity applications. To this end some NAS models are equipped with the ability to support most virtualisation solutions to enhance work efficiency whilst keeping an easy management interface.

Check for compatibility if you're looking to use your NAS in this way.