NAS shoot-out: 5 storage servers battle for business

Rsync allows you to synchronize your files automatically to another box. Instead of copying all of the data each time, rsync copies over only the changes or differences, minimizing both bandwidth requirements and copy time. Rsync is a perfectly good way to back up the NAS, but it is harder to set up than the replication solutions from the likes of Iomega and Netgear. These make NAS backups a snap even for nontechnical users. In Netgear's case, it also provides the ability to manage several NAS boxes from one Web-based interface to do file replication across multiple sites (albeit at additional cost).

Then there's "cloud backup" -- using backup software that copies the data on the NAS to a cloud storage service. Typically, these services charge a monthly fee that depends on the amount of data you need to store on their servers. Procedures are in place to ensure the privacy of your data via encryption and security policies. Iomega and Netgear use their own cloud storage solutions, but other NAS manufacturers such as QNAP offer backup to third parties such as Amazon S3 and ElephantDrive.

NAS shoot-out: Advanced features
iSCSI (Internet Small Computer System Interface) is a feature that many small businesses should keep in mind. Even if you might not use it today, it offers flexibility you might very well appreciate in the future. In a nutshell, iSCSI gives the illusion to a server that it has locally attached storage when that storage is in fact running off the NAS. It is a perfect way to consolidate your data in one location while also giving your Web server or database server the "local" storage it requires.

A feature that is useful in Windows shops is Active Directory integration. By tying into Microsoft's directory service, you can enforce file-level security on your NAS. With this integration, you can easily set up security to certain areas and directories based on the groups that an employee may belong to. All of the NAS boxes in this review can work with Active Directory.

UPS (uninterruptible power supply) monitoring is not something you typically find in smaller businesses, but I would recommend using it. Most newer UPSes have USB interfaces that allow you to connect them directly to the NAS hardware. Not only would you want your NAS on this battery backup (this is a must), but the UPS will also help the NAS to gracefully turn itself off if a power outage lasts too long.

Apart from cloud, virtualization is the buzzword you'll hear most frequently bantered about in this segment. While many large companies might use these NAS boxes to store virtual server images, few small companies are managing virtual server farms at this point. Nevertheless, every NAS box in this roundup is certified for use with VMware.

NAS shoot-out: Everything else but the kitchen sink
All of the NAS boxes in this roundup have the flexibility to do more than merely store your data. These features are too numerous to review in detail, but they include such things as the ability to collect images from IP video surveillance cameras, mobile apps that allow you to access your data from iPhones, iPads, and Android devices, and multimedia servers that provide access to photos, music, and video.

In addition to the built-in features, you can generally install software packages that extend the functionality. Typical add-on modules include BitTorrent downloaders, email servers, and content management and blog publishing applications.