Computers / Hands-on Review

Drobo Storage Arrays Provide Simple Redundancy


There was a time when only large corporations used RAID storage. It was partly because only large corporations had enough data to warrant the use of RAID storage and partly because only large corporations could afford to purchase and maintain such high-end storage. RAID storage is still used by large corporations, but today you’ll find that RAID storage is also used by small businesses and individuals. That’s because RAID storage is now affordable and easy to maintain, and lots of ordinary folks are now in possession of huge amounts of data. If you’re looking for a hassle-free point of entry to RAID storage, consider Data Robotics’ Drobo storage arrays.

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RAID stands for Redundant Array of Inexpensive Drives. The technology basically allows data to be spread across multiple hard drives so that if a drive fails, the data can be recovered from the drives that remain intact. RAID is becoming more and more important as hard drives grow in capacity because you stand to lose a lot of data when a big hard drive fails.

Drobo storage arrays combine data protection, convenience and affordability. They come in various configurations with different numbers of drive bays, different types of interfaces and with and without the hard drives themselves. Regardless of your budget and storage requirements, you should be able to find a Drobo product that meets your needs. Here we’ll look at a few units that are good for photographers or video editors as well as some that are better suited for small business and enterprise use.

Drobo 4-Bay Hard Drive Array Enclosure

The most affordable array is the Drobo 4-bay Hard Drive Array Enclosure with FireWire 800 and USB 2.0 interfaces and no hard drives. You just start with whatever drive you have, though it must be SATA, and add more drives as you need them. If all of the bays are full, you can increase capacity by replacing a drive with one that has a larger capacity, without costly down time. You just replace the drive and Drobo does the rest. Note that you need at least two drives to have any kind of redundancy, but you can mix and match drives of different brands, capacities and speeds. And when you remove disks from the array you can put them back in any order you like. All Drobo arrays support hard drives up to 4TB.

The Drobo storage arrays incorporate Data Robotics’ BeyondRAID technology, which can protect data even when multiple drives fail. BeyondRAID supports Windows and Mac operating systems, with file system support for NTFS, HFS+ and FAT32. When a hard disk fails, the Drobo array automatically enters a self-healing state in which data residing on the defective drive is spread across the remaining healthy disks and the array is brought back to the safest state possible. Ideally, at this point, you should replace the bad drive to restore capacity and redundancy.

BeyondRAID uses a technology called virtualization to place a layer of abstraction between the data requested by the file system and the physical location of the data within the array. That way BeyondRAID can reconfigure the array on the fly without interrupting user access.

When Drobo detects a bad drive it issues various warnings, including a blinking red LED, pop-up alerts in Drobo Dashboard and email alerts if it’s configured to send them. Drobo Dashboard provides a simple means of interacting with the array, and the latest version of Drobo Dashboard (version 2.0.2) lets you view the status of all of your Drobo units in one window.

Purchasers of a Drobo unit can also download Drobo PC Backup software for free. The software makes it a simple matter to back up your computer, and it supports direct backups over USB, FireWire or eSATA, as well as network backups.

To provide redundancy, you need to have at least two drives in an array. And without getting complicated, the total amount of storage space in an array is roughly equal to the number of drives in the array minus 1, multiplied by the capacity of the smallest drive in the array. So if you have a 4-drive array, with each drive being 1TB, you end up with an array of approximately 3TB with the fourth drive used to provide redundancy. There’s an excellent tool on the Drobo website that shows you exactly how much storage space you can expect from any of the arrays, depending on how many drives you’ve installed and the capacity of each drive (

Drobo S 5-Bay Hard Drive Array Enclosure

Each drive in an array plays a critical role, and adding just one more drive can add up to 4TB of storage space to the array or provide double the redundancy protection. That’s why the Drobo S 5-Bay Hard Drive Array Enclosure is a lot more sophisticated than the 4-bay model, at least as far as functionality is concerned; managing either unit is just as simple. Not only does it give you four drive bays for storage and a fifth for redundancy, you can also configure it to use two drives for redundancy and three for storage. That way the array is fully protected against data loss even if two drives fail at the same time.

Enabling dual-drive redundancy is easy. From within Drobo Dashboard you simply click on the setting and the array is protected against the failure of two drives. If the array is running out of space you can always switch back to single-drive redundancy with a click of the mouse. In addition to having five drive bays, the Drobo S also features a wider variety of interfaces, including USB 3.0, eSATA and FireWire 800. Like the 4-bay Drobo, the Drobo S allows the mixing and matching of different hard drive brands, capacities and speeds, although they must be SATA drives. The purchase of a Drobo S also entitles you to a free download of the Drobo PC Backup software.

Drobo FS Network Storage Enclosure

Network storage serves two main purposes. One, it serves as a safe place for users to store important data. Two, it’s a place where any network user can store some information so that other users can access it. That’s known as file sharing. For proper integration with a network, and to ease file sharing among multiple users, a storage array really should have a network port. This is where the Drobo FS Network Storage Enclosure comes into play. Like the Drobo S, the Drobo FS is a 5-bay storage array that supports SATA hard drives up to 4TB in size. But the Drobo FS lacks any direct-connection ports, instead featuring a single gigabit Ethernet port. That allows easy network integration, fast throughput and simple file sharing among users.

In addition to its Ethernet port, the Drobo FS offers secure and hot-swappable BeyondRAID storage and includes the Drobo Dashboard and Drobo PC Backup software. Drobo supports Windows, Mac, UNIX and Linux, so pretty much any computer can connect to it. And since Drobo PC Backup supports network backups, it’s easy to keep all of the attached computers fully backed up. The Drobo FS can, of course, be configured for single- or dual-drive redundancy and it provides seamless support for Apple Time Machine.

The three Drobo units we’ve looked at so far are ideal for individual users. Now let’s take a look at some are better suited for small business and enterprise use.

Drobo B800fs 8-Bay Network File Sharing Storage

The Drobo B800fs Drobo 8-Bay Network File Sharing Storage has bays for up to eight 3.5-inch SATA I/II drives. It also features two gigabit Ethernet ports for easy network integration and fast throughput. The ports can be configured to switch over if one link fails or they can be used to connect the array to two separate networks.

Other than having more drive bays, the B800fs is just as easy to use as any other Drobo unit and it’s based on the same hot-swappable BeyondRAID storage technology. An added bonus is Drobo Sync, which makes it easy to back up one B800fs to another B800fs in a remote location. This provides valuable protection against floods, fires and theft. You can use Drobo Sync to set up a backup schedule that will take place automatically at a convenient time, typically at night when users are at home sleeping. The Drobo B800fs is designed to be rack mounted, but it works just as well sitting on a desk and is quiet enough to not create a distraction.

The Drobo FS series storage arrays support DroboApps, which are community-created and community-supported applications that will run in the Drobo FS series’ Linux-based operating system; Drobo does not provide direct technical support for these apps. But if you’re interested in any of them, the first app you should install is the DroboApps Admin Utility, which simplifies installing, configuring, updating and uninstalling other DroboApps. The DroboApps currently include Apache web server, FUPPES Media Server, Firefly music server, CTorrent bittorrent client, Lighttpd HTTP server, Pure-FTPd FTP server and others.

Drobo B800i iSCSI SAN Storage Enclosure

Similar to the B800fs is the Drobo B800i iSCSI SAN Storage Enclosure. The B800i features eight 3.5-inch SATA drive bays and two gigabit Ethernet ports, along with the BeyondRAID technology, Drobo Dashboard and all the other handy features. But the B800i is designed for use in iSCSI SAN environments and adds compatibility with VMware vSphere and Citrix XenServer operating environments.

Drobo B1200i iSCI SAN Storage Enclosure

All of the Drobo units we’ve discussed so far come as bare storage arrays with no hard drives included. But some configurations include hard drives. The Drobo 12TB B1200i iSCSI SAN Storage Enclosure is a 12-bay unit with four gigabit Ethernet ports (three for data and one for management) and support for 3.5-inch SATA and SAS drives. It also includes six 2TB SAS hard drives. According to the Drobo Capacity Calculator, the six 2TB drives yield a total actual size array of 10.91TB, with 8.71TB available for data and 2.19TB used for protection, and that’s with the array configured for single-drive redundancy. Switching to dual-drive redundancy yields an array with 7.26TB available for data and 3.56TB used for protection.

If you need even more storage space you can purchase the Drobo 24TB B1200i iSCSI SAN Storage Enclosure, which includes twelve 2TB SAS hard drives. According to the Drobo Capacity Calculator, the twelve 2TB drives yield a total actual size array of 21.82TB, with 19.74TB available for data and 2.08TB used for protection when configured for single-drive redundancy. Switching to dual-drive redundancy yields an array with 18.15TB available for data and 3.66TB used for protection.

Click here for Spec Sheet and Comparison Chart