Choose a NAS box

Considering network-attached storage? We test five recent models

A NAS is effectively a small PC running its own operating system, with apps for various server tasks. At home, it’s commonly used for keeping collections of music and video files that can be played from anywhere. The NAS itself can be connected to a TV as a home entertainment centre. You can also use it to store and display photos, host websites, control security cameras and more, and to store any shared files. There may be ports to access USB drives or printers too.

Most affordable NAS boxes have two or four drive bays containing multiple hard drives, which will appear as one volume. Hard drives don’t last forever, and when you set up your NAS you can choose a configuration that balances risk against speed and space. One option is JBOD – ‘just a box of disks’ – which presents the drives as individual volumes, which you access separately, or ‘spans’ the drives as one volume matching their total capacity. In this latter case, when one fails you’ll lose a random half or quarter of your files.

RAID (Redundant Array of Independent Disks) is the system used by NAS drives to store data efficiently and automatically back up computer hard drives. RAID0 ‘stripes’ data across the drives, increasing speed, but if one fails you’ll lose everything.

RAID1, the sensible option, ‘mirrors’ two drives, so capacity is halved – buy two 2TB drives, get 2TB of space. But if one fails, all your data is safe – just make sure you replace it immediately. With four bays, RAID5 gives you three-quarters of the total capacity and will survive any one drive failing, while RAID6 gives you half and will survive two failing at once. RAID isn’t invulnerable, and it won’t stop you accidentally deleting things, so you still need to back up crucial files separately.

Your NAS connects to your router with an Ethernet cable, from where you can access files from any PC on your network and usually from mobile devices. Most NAS software now supports onlinestorage functions, so you can access files over the internet and back up data ‘in the cloud’. We don’t have room here to list all the features of each box, so check the web link under ‘Specifications’ before you buy.

We tested five NAS boxes under £300. That’s without the hard drives, which you can easily add yourself, or may be offered as an option. Any 3.5in SATA drive can be used, but they should all be of the same capacity. You could buy, say, two 2TB Seagate Barracuda drives (£50 from Amazon www.snipca.com/27876) for as little as £100. It’s probably worth paying a little more, though, for a Nas-rated drive like a Seagate Ironwolf or WD Red (£63 from Amazon www.snipca.com/27877), which are built for greater reliability and add error-recovery features to help RAID setups survive problems.

If you want something cheaper, Buffalo’s two-bay Linkstation 520ED (£87 from Amazon www.snipca.com/27878, pictured) has only basic file sharing, and music and video-streaming features, but it’s good value.