I’ve been toying with the idea of making a Network Addressable Storage (NAS) device for home use from scratch. For all intents and purposes, I already have. I’ve got an old machine that I built several years ago assigned to the task, as well as serving the network router, firewall and DNS cache. It has also recently come to my attention (via a newly acquired Kill-A-Watt power meter) that this machine sucks in roughly 120 Watts of electricity by itself. At roughly 10 cents a Kilowatt-hour, this comes to over $100 just to leave the machine on. Here I thought I was doing well by consolidating several devices (USB hard drives, router/firewall) into a single machine, but the power consumption of this one machine significantly outweighs the total of the smaller devices.

This got me thinking about what features I would want in my ideal NAS device. At a very high level, I want a device that stores and protects large volumes of data and does not impose itself on my daily life.

Reading back over the above high level requirement, I’m surprised how simple it sounds, yet how broad and non-trivial it really is. To break this down a bit more, I will dissect this sentence into more specific desires.

A Device that Stores and Protects Large Volumes of Data

• My and my family’s need for storage space is forever increasing. If this machine is going to satisfy my needs long term, its storage space will also need to grow.
• Data redundancy across two or more hard drives is an important step toward safeguarding against data loss. As such, RAID should be a key feature.
• “Dirty” or unreliable power can be damaging to any computer. A secondary power supply like a UPS or integrated battery similar to a laptop would help to remediate this risk.
• A case with sturdy construction, low center of mass and low profile would help to protect the device from minor bumps in high traffic areas.
  

Certainly, there are many other concerns when protecting data, but I am talking about a NAS device, not a disaster recovery plan.

Does Not Impose Itself on My Daily Life

• Minimal and easy maintenance. When something starts to go wrong, the system should notify me. Adding or swapping drives shouldn’t require a tool chest and manual.
• File transfers to and from the device should be fast, even for large multimedia files.
• Sharing files with Windows and Unix operating systems should be seamless.
• Quiet and aesthetically pleasing. The device shouldn’t draw any special attention when walking into a room due to bulky, ugly and loud construction. This is my primary reason for placing my current machine in the basement.
• Initial construction and running costs should be economical and environmentally green.

Devices similar to what I describe are already available on the market. For example, the Drobo “data robot” from Data Robotics, Inc. in combination with their DroboShare will do most of this for around $700 plus the cost of the hard drives. Still, I’m going to look into building one myself, even if only on paper. It would be fun to build, and I may even be able to one-up the Drobo by making my device more general purpose. For example, maybe I can make it a thin Linux machine that uses my 32 inch LCD TV as a monitor or a MythTV box using my HDHomeRun digital TV turners.