N ot every business needs a fully
fledged server, and it would
certainly be unusual if you had
one at home. Often, it’s the ability to
share files across a network that drives
people to purchase a server, particularly
small businesses. But if this is all you
need, you’re better off with a networkattached
storage (NAS) drive. A NAS
drive is essentially a mini-server with
the advanced capabilities stripped out –
although many models allow you to add
them back again via apps. This month
we test ten NAS drives from some of the
leading manufacturers in the field.
The most advanced NAS drives
come in a rack-mountable chassis,
intended to be installed in multiples or
to supplement full servers in a dedicated
rack. In this test, however, we’re focusing
on a selection of two- and four-drive
standalone NAS devices aimed at small
businesses and home users. These are
intended to sit on your desk, on a shelf,
or even on the floor somewhere, and are
relatively small and unobtrusive
When you are selecting such a device,
the first question you need to ask is
what you’ll use it for. Will it be simply
a network backup device or will it also
act as a shared media server? Are there
any other server-type uses you’d like to
take advantage of? Then consider how
much capacity you need, and whether
you want room for expansion. Some NAS
boxes are sold pre-populated, but others
require you to supply disks yourself – and
only selected drives will be compatible.
Power consumption is important, too,
since you’ll most likely leave your NAS
device on around the clock, so that it’s
available whenever you need it.
A key feature of a NAS is the ability to
configure the installed disks in a variety
of different ways. The options available
on your device will depend on how many
drive bays it has and how many of these
are populated. With a
two-drive device, the simplest options
are to configure the drives as separate
volumes, or to concatenate them into
one logical drive: these arrangements are
sometimes called “JBOD” configurations,
which stands for “just a bunch of disks
For most purposes, it makes sense to
set up your drives as a RAID array (the
name stands for “redundant array of
inexpensive disks”, although if you’ve
invested in hefty 4TB volumes you might
quibble with the description). There are
several options here, offering different
balances of performance, capacity and
security (see Choose the right RAID level,
opposite page)
Beyond drive configurations,
the networking features should be
considered. All this month’s devices have
one or two Gigabit Ethernet ports, but
the protocols they support vary a little.
The most basic is Server Message Block
(SMB), which allows Windows devices
to access the storage over the network.
Apple Filing Protocol (AFP) is Apple’s
equivalent, although OS X devices are
SMB-compatible too, and Network File
System (NFS) is the Unix/
Linux equivalent.
HTTP compatibility is required if you
want to access files over a web browser
interface, while FTP support allows
this protocol to be used to upload and
download files. WebDAV is an extension
of HTTP that allows writing as
well as reading. For more
enterprise-level connectivity,
some of this month’s
devices support iSCSI,
which allows the network
drive to behave like an
SCSI-attached local disk –
beneficial for software that
expects locally attached
volumes.
MEDIA SERVERS
Home users will be looking
for a few different features.
In particular, there’s a good
chance you’ll want to use
your NAS drive as a media
server for all the devices in
your home network. The core
functionality here is UPnP/
DLNA compatibility, which is a widely
used protocol for sharing video, music
and pictures in a read-only fashion
between devices. All of this month’s
NAS devices support it, and there are
even smart TVs that can stream media
in this way. For music lovers, iTunes
compatibility means that the NAS device
will conveniently show up automatically
in your iTunes library
Data backup from all of your network
devices is likely to be the bread-andbutter
task for a NAS server. A number of
this month’s entries come with backup
software and multi-user licences,
but if you’re using OS X systems then
support for Time Machine will be greatly
beneficial. Some NAS manufacturers
also offer apps for smartphones and
tablets that you can use to access your
files. You may want to share data outside
your local area network. This is where
the aforementioned HTTP, WebDAV and
FTP support will be beneficial, although
this can lead to security risks (see
Securing your NAS device, p70).
Many of this month’s devices also
allow you to extend their capabilities
by installing additional applications,
including PHP frameworks that turn
these storage servers into general web
servers for hosting blogs, forums, or
even e-commerce sites. It’s debatable
whether it’s wise to host such things
from a NAS drive, but the option is there.
Whatever you intend to use your NAS for,
there’s a huge range of options available,
so study the reviews to fi nd out which
has the features to match your budget
and needs.
HOW WE TESTED
As well as comparing the features of
each NAS device, we ran a series of
performance tests on each of them,
to simulate regular everyday usage
scenarios. First of all, we measured the
best possible performance by copying
a large 1.96GB single fi le to the device
and back again. If you store a collection
of audiovisual content, this will give you
an idea of how quickly you’ll be able to
retrieve large video fi les.
For more general throughput, we
copied a 10.6GB collection of smaller
fi les to the NAS device, simulating
backup operations.
All of these tests were performed
across a Gigabit Ethernet network to
minimise network bottlenecks, and
the host system for copying was an
Overclockers Renda PW-E7F workstation
with fast SSD primary storage, again to
ensure that the NAS setup was getting
the best data delivery possible.
For the same reason we used a Gigabit
network, with only the NAS device, router
and workstation on it. Using a power
meter, we measured the number of
watts consumed when the NAS device
was idle and performing the multi-fi le
backup test.
For the NAS devices that came
without drives, we used the same set of
3TB WD Red hard disks – either two or
four, depending on the model.
Since fault tolerance is more
important than performance for a NAS
drive, we confi gured RAID1 (mirroring) for
two-drive devices, and RAID5 for fourdrive
devices.
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