Drobo
Tuesday, June 22, 2010 at 5:06PM Preface
Please see also the excellent information on Drobo's web site which includes a capacity calculator, images of the units and most other pre-sales information you will need.
What is a Drobo?
Drobo manufacture a number of external RAID-like storage solutions. They all feature a number of drive bays, between 4 and 8, a variety of connectivity solutions and their own system for managing the usable capacity the drives. Unlike conventional RAID you can use any combination of drives, they do not need to be of the same capacity or from the same manufacturer. Having installed two or more drives, the Drobo will calculate how much storage is available and how much is required for redundancy. Any single drive in a Drobo can fail and your data remains secure, the larger solutions can be configured to allow for two simultaneous drive failures with our data corruption. Drobo even supply an online capacity calculator to allow you to see how much storage you will get when drives are installed. Additional drives can be added to empty bays at any time, allowing you to grow your array as you need to.
How does my set-up work?
A little background would be useful here before explaining why I chose to buy a Drobo. My main workstation is a Mac Pro running Snow Leopard with three internal drives, the boot disk and two, mirrored "working" drives that store all of my photography once it's imported into Aperture from CF cards. I still use internal drives for my working data, the Drobo is used for archived images I only need access to from time to time.
Why did I choose a Drobo?
Besides needing somewhere to offload the images I was no longer working on, I had some other information on single drives that really needed better protection, I had the spare drives sitting around and I had heard Drobo through podcast sponsorship. It seemed like a good way to use my existing drives and get all of that data onto a device that offered protection against a drive failure. Due to budgetary constraints and the amount of data I currently needed to store, I opted for a 4 bay Drobo with Firewire 800 and USB, the base model.
The Drobo in use
It's really simple! Just put two or more drives into the enclosure (they slip in easily and a clip holds them in place), connect to power and your computer with the included cables – in my case I chose a Firewire 800 connection – install Drobo Dashboard and off you go. That's it! The only configuration that's required is formatting the disks and naming the array. I installed the two 1.5TB drives I had been using as my working drives plus a third 1.5TB drive to get things going. This set-up balked on the first attempt to format the Drobo but went smoothly on the second go. After that the only other problem I encountered was when trying to download Photoshop CS5 from the Adobe store directly to the Drobo, after about a minute the Drobo reset itself and rebooted, no data was lost though, it was a bit alarming nonetheless. I suspect the problem is an incompatibility with the download system Adobe uses, it worked fine when using my boot drive. Since then the Drobo hasn't missed a beat. It should be noted that I have added another 500GB drive to the Drobo since installing it with the three 1.5TBs. What amazed me was that the additional capacity was available immediately after the new drive was installed. The Drobo Dashboard software gives you an overview of how your drives are being used and allows you to configure your Drobo, it is not a requirement to access the data on the Drobo and does occasionally fail to connect to mine, a problem solved by rebooting the host machine. For those of you who are super-sensitive to noise, the Drobo does mask the clicks and whirs you expect from hard disks but it does have a fan which runs all of the time, occasionally kicking up a gear if you use the unit heavily, its not a noisy fan, nor is it as quiet as the ones in a modern Mac Pro.
Throughput
It takes a while to move the amounts of data a Drobo can store around and it has to be said that it's not the most blisteringly fast of devices, at least not in this Firewire 800 incarnation. So, to give you an ides of some real-world performance figures, I've done some tests. I have taken a folder from one of my shoots, containing 3.12GB of data in 302 files and copied it in the following ways:
- Internal boot disk to the 2x750GB internal mirror in my Mac Pro
- Internal boot disk to a single Firewire 800 external disk
- Internal boot disk to Drobo via Firewire 800
As you can see, there is quite a speed overhead for the protection the Drobo offers, so you should take this into account when specifying your system. Unfortunately I have not been able to test a Drobo S, which offers 5 drive bays and a faster eSATA interface. I would have to imagine that the Drobo S also has faster internal processing, as you can see from the graph it is the Drobo, rather than the connection, that is causing the bottleneck.

All times are in minutes and seconds, correct to the nearest second.
Conclusions
I've set-up quite a lot of RAID solutions and Drobo really does take the headache out of it. No worries about matching drive sizes and manufacturers, no waiting around for hours for arrays to build before you can use them. Yes, there is an overhead in speed, but this is not a hinderance to the way I work, my current working data being on fast, internal disks. Taking this into consideration I would definitely recommend a Drobo, the model I have comes in at about £300, if you need the extra speed, consider the Drobo S for around £500.

















