The Flexibility of Network Attached Storage (NAS)

Original Article Date: 2005-04-22

You might of heard of NAS - it's the latest acronym in corporate networking that is being plastered all over the web and magazine-ads. But what exactly is it?

You are quite likely to know that NAS stands for Network Attached Storage, and that basically tells you what it's about. NAS allows you to "plug" massive storage directly into your network, allowing great flexibility in accessing or adding storage that can be used across your network.

Traditional Network Storage Architectures

Traditional networks only allowed data to be stored directly onto network servers. For instance, if you were running a web server, an e-mail server and an internal / departmental file server on your network, each of these servers would be responsible for providing its own storage.

The problem with this architecture is that it's inflexible. Should one of these servers outgrow its storage capacity, you'd have to start getting into expensive and complicated hard drive upgrades. And sometimes, the limitations of the server's physical size would prevent meaningful upgrades, and so in these cases you'd have to replace the entire box.

This model also suffers from potential inefficiency. Whilst on one hand you might not have foreseen the dramatic increase in space needed on your e-mail server, you might equally have over-estimated the storage required by the web server, which is now using only a third of the drive space originally intended for it.

The solution to these problems is separating server space from storage space.

NAS - Separating Server Processing from Storage

Network Attached Storage is, logically speaking, attached directly to the network. So you don't have to associate or attach it to, or go through one of your servers to obtain storage over the network. In essence, the network storage has become modularized, providing enormous flexibility in how your plan or grow your storage requirements.

By de-coupling your network storage from your servers, you free them up to do exactly what they were intended for. Web servers are there to process and handle requests from internet visitors. E-mail servers process internal and internet-based e-mails. These servers are essentially processors, not storage bins! Of course, each needs to store web and e-mail content , but these can be stored on modular storage attached to the network.

In that way, as the processing demands of each server change and grow over time, upgrades to CPUs, RAM or entire systems can be made independently to demands placed on them in regard to storage.

The upshot of this is reduced TCO (total cost of ownership) and, of course, reduced headaches for your IT administrator in planning out network storage!

But what's inside a NAS Box?

A NAS box is regarded as a Network Appliance (such as a hardware firewall, router or spam-filter), in that it plugs into your network and almost immediately begins performing a function. In the case of NAS, this is exposing a small or large number of hard-drives to the network as one or more useable storage volumes.

Essentially, the NAS appliance is an entry-level server, utilising a low-cost Pentium®4 CPU, which performs the basic I/O operations needed. A relatively inexpensive P4 motherboard, equipped with one or more gigabit LAN ports provides overall physical connectivity with the network, and with the RAID controller which acts as one or more logical drives.

The beauty in NAS appliances is in the operating system. An OS that only needs to handle disk operations is very simple, and in the case of Open-E® NAS, which we use on our NAS appliances, can be fitted onto flash-memory which plugs into the IDE slot of the mainboard.

Having the OS on a dependable flash memory module allows the user to configure their storage using 100% of all physical drives in the box. Not all NAS solutions are as elegant as this, however, as some NAS operating systems need to be stored on some portion of the hard drives, and protected from failure using RAID1 - it gets complex.

Setting up NAS in minutes

NAS appliances such as those incorporating Open-E® can be configured in minutes to provide terabytes of storage. A typical sequence, after receiving your NAS Appliance from us would be:

1. Locally set up the RAID Controller (in the controller card's BIOS) to expose one or more logical disk volumes.
2. Connect your NAS appliance to your network.
3. Access the NAS appliance configuration utility using a web browser from any machine on your network.
4. Configure your drive shares, user privileges, tape back-up schedules etc. from the NAS interface.
5. Start using your NAS as one or more network drives!

NAS Solutions from Electronics Nexus

Electronics Nexus offers a range of customizable  NAS Appliances starting at $2,199. The main differences between the six different solutions we offer are maximum storage size and whether they come with Serial ATA or SCSI drives. All NAS Appliances come with hot-swappable drive bays, 2 gigabit LAN ports, a RAID controller and the Open-E® NAS Operating System on a flash-memory card that plugs into one of the IDE slots.

If you think you might have a need for flexible storage that can grow independently of your existing server needs, feel free to give us a call. I'll be happy to answer any of your questions, or to help you choose which appliance is the right solution for your needs!

Best regards,

Ben Ranson
Chief Systems Engineer