Data Robotics Drobo S Review

The Drobo S can work with versions of Windows going all the way back to Windows XP; it can also work with Mac OS X 10.5 and newer; and the Drobo S even has beta support for Linux. The first step in setting up the Drobo S is to install the Drobo Dashboard software on your system--there are Windows and Mac versions of it. Once the software is installed and running, you next install at least two SATA hard drives into the Drobo S device--the drives slide right into slots on the front of the device, without need for any rails or tools. You then power up the unit and attach it your system via the eSATA, FireWire 800, or USB 2.0 connectors on the back of the device.


Depending on your system, you might run into some compatibility issues with the eSATA or FireWire connections. For instance, initially whenever we attached the Drobo S to our Windows 7 testbed via the eSATA connection, our system always crashed, displaying a BSOD (this was the first time we ever experienced this issue with an eSATA device attached to our testbed). So we swapped out the eSATA controller card with one that Data Robotics reported was known to be compatible with the Drobo S, and then all worked fine. We ran into a similar issue with FireWire where we couldn't get our system to see the Drobo S using our testbed's built-in FireWire connection, and instead had to use a FireWire add-in card. If you want to use the Drobo S with a system’s FireWire 400 connection, you’ll need to purchase a FireWire-400-to-FireWire-800 adapter (which you can typically find for around $10). If you use the eSATA or FireWire connections you also might need to experiment with the order in which you connect the Drobo S to your system--in some cases, the Drobo S needs to be powered on and connected before your boot up your system; and in other cases, you might need to wait to connect the Drobo S until after your system has booted into the OS. That said, the USB 2.0 connection appears to work flawlessly, without any issues at all.


Once the Drobo S is successfully connected to your system and the Drobo Dashboard senses that the device is attached, you’ll see a message telling you that the device’s drives aren't formatted, and asks you if you want to format them. On a Windows system, if you click yes, you are taken to a screen that gives you the option of formatting the drives using a Windows XP-compatible version of NTFS (which limits volume size to 2TB), a Windows Vista (and newer)-compatible version of NTFS (supporting up to a 16TB volume size), or FAT32 (also limited to a 2TB volume size). (On the Mac, your choices are HFS+ and FAT32 file systems. If you want to format the drives as EXT3 for a Linux system, you need to follow the instructions here). Once you pick your file format, you then choose the size of your volume, name the volume, and map a drive letter to it. After you've made these selections, the Drobo S goes to work formatting the drives to appear as a single volume. You can also set up multiple volumes if you want. If you see a Windows OS message pop up saying "You need to format the disk in drive x: before you can use it. Do you want to format it?", ignore it and click cancel.

Formatting the file system for use with the Windows OS (left) and the Mac OS (center); changing the Dual Disk Redundancy setting (right)

Once formatting is complete--which should only take a few minutes--the Drobo S is ready for action. By default, the Drobo S is protected against the failure of a single drive. You can, however, choose the "Dual Disk Redundancy" option to protect against the failure of up to two drives. If you choose Dual Disk Redundancy, however, you will have less available storage capacity. With our unit, we installed five lightning-fast 2TB Seagate Barracuda XT hard drives--when configured for single-drive protection, we had 7.22TB available for data storage, and 1.86TB reserved for protection; when configured for dual-drive protection, we had 5.4TB available for data, and 3.69TB for protection. You can switch back from dual-disk to single-disk protection if you want, but this conversion can take quite a bit of time (i.e., hours), depending on how much data is already stored on the drives--but if you need to access it during this conversion you can still read and write to it. Even when a drive fails, you still have full access to the device and the data stored on it--or even two failed drives if you are using Dual Disk Redundancy.

Storage capacity when set for single disk protection (left) and Dual-Disk Redundancy (right); converting the data protection from single to dual disk protection (center)

The front of the device has a set of LEDs that displays color-coded health information for each installed drive. The lights will be green, orange, or red, and solid or blinking, depending on the health of individual drives or the array--such as warning of a failed drive, a drive that is almost full, or that the device is in process of rebuilding the data protection. The Drobo Dashboard will also alert you if there is a problem. You can even configure the Drobo Dashboard to send you e-mail alerts if anything out the ordinary happens with the device. The Drobo Dashboard also includes a utility for setting up multiple, automated data backups.

Storage capacity with five installed drives (left) and three installed drives (right); automatically resetting the data protection after "losing" two drives (center)

With our Drobo S configured for Dual Disk Redundancy, we removed two of the five installed hard drives. Lights started flashing and warning screens popped up, but the device kept working--we could still read and write to it and none of our data was lost. We plugged in replacement drives and the Drobo S automatically started to rebuild the array and resetting data protection. In our experiment, it took the Drobo S about six hours to rebuild the array; and during this time, data transfer performance was noticeably slower.

Drobo Dashboard: Advanced Controls (left); E-mail Settings (center); examples of multiple scheduled backups (right).

At any point you can add more drives to the device if all five bays aren’t already populated--and the Drobo S will automatically format the new drives and add them to the array. You can also remove a drive and replace it with a larger capacity drive and the Drobo S will once again perform its automated magic. Try this with a traditional RAID device and you won't be very happy with the results.