Network-attached storage is a pain. That's not because the hardware vendors aren't selling the stuff, or because it doesn't work. In fact, demand for storage has never been higher, so it clearly does work.
The problem comes when a company grows beyond the limits of a few NAS boxes and needs more storage. Lots more storage.
Today, NAS comes in a standalone box, and there's not a lot you can do with it other than store data. You can't scale out because the box doesn't permit it, and you can't scale up without buying a ton more storage to upgrade the disks, even assuming that is a simple operation. If you've got more than a basic configuration, chances are you won't want to go too far down this road.
Scale-out NAS boxes
So what's the answer? Storage vendors at the top end are providing scale-out NAS boxes — EMC Isilon is an example. To add more storage, you add a box and it becomes part of the system.
It's managed from the centre, and allows you to enlarge your storage pool using a single name space, without having to shift terabytes of data around to balance the load across multiple boxes.
Feature sets in scale-out NAS are becoming richer — you're getting more products with synchronous replication
As well as reducing the amount of time spent on management per gigabyte, scale-out means savings on power and cooling too, as you're not running as many separate units, each with its own built-in infrastructure.
That's not true where most companies live. Here, you buy storage in discrete units and then have the increasingly tedious task of managing a growing farm of storage devices. If you don't manage them in this way, you run the risk of paying for storage you're not using, and overloading some boxes to the point where performance suffers.
This problem is particularly common where applications are tightly tied into one or two of the devices, and upgrading then becomes a major headache, perhaps also associated with downtime as you move the bits around.
Richer scale-out feature sets
However, there's some light at the end of the tunnel. Scale-out NAS has traditionally been aimed at organisations with a need for large volumes. Examples would be media companies, and those using scientific data, so large data sets have been prioritised over enterprise style features such as deduping, snapshotting and replication.
According to analyst Arun Taneja, founder and consulting analyst at Taneja Group, feature sets in scale-out NAS are becoming richer — you're getting more products with synchronous replication, for example — and those enterprise-level features are arriving in scale-out NAS products aimed at smaller organisations. And analyst Terri McClure from Enterprise Strategy Group believes that most data storage will be on scale-out NAS in the next few years.
Some would suggest pushing all that data into the cloud. But as we all know, the network is still neither reliable nor fast enough for mission-critical applications, although some cloud storage service providers are getting around this problem by using cacheing gateways at the edge.
Hmm, more devices to manage and cool — and this type of technology is still young, so most organisations will probably wait for version 3.
In the meantime, the time for NAS to get smart is overdue.