Drobo 5D review
A good-value, high-performance Thunderbolt DAS appliance with smart RAID and data-tiering features
We've been impressed by Drobo's innovative approach to RAID in the past, and its new 5D carries on the good work. It's the first multibay DAS appliance we've come across with both USB 3 and dual Thunderbolt ports, and it's aimed at professional Mac users who want high-performance local storage with fault tolerance.
The 5D has an internal lithium ion battery to protect against power cuts, and it supports Drobo's data-tiering system, so it can move regularly accessed data onto an optional mSATA SSD for increased read speeds. Up to six 5Ds can be daisy-chained together with Thunderbolt cables.
Drobo's mantra has always been to simplify RAID for those who want all its benefits but none of the hassle. The 5D adheres to the same philosophy: simply slip five SATA hard disks of any size into the appliance and Drobo's BeyondRAID will automatically add them to a single virtual storage pool with redundancy configured at the block level.
The 5D's front panel tells you everything you need to know about storage status. The drive indicators change from green to yellow or red if any drives need to be swapped out for larger ones, or if they've failed, and a line of blue LEDs below acts as a capacity gauge.
Similar to RAID5 and 6, BeyondRAID supports single and dual parity. Either can be selected on the fly, and Drobo remains the only vendor to allow you to return from dual to single parity.
We tested using a 13in MacBook Pro with a 2.3GHz Intel Core i5, 4GB of DDR3 memory and OS X 10.8.2. Installation was simple: once the Dashboard utility is downloaded, the 5D can be connected via Thunderbolt or USB, where it's spotted immediately.
Thin provisioning is standard, so, during virtual volume creation, capacity can be set between 1TB and 16TB regardless of the number or sizes of the physical drives. Initially, we loaded the 5D with a pair of 3TB WD SATA drives and chose a single, 16TB HFS+ formatted volume.
Thin provisioning dynamically allocates blocks as they're used, and increasing physical space is a cinch. We added two 4TB WD SATA drives in succession; each time, the Dashboard acknowledged their presence and added them to the array without the need for intervention.
For performance testing, we used Intech's QuickBench 4 software. We ran it first on the MacBook's internal drive, and saw sequential read and write speeds of around 80MB/sec for 1,024KB blocks of data. Running the same test on the 5D over a Thunderbolt link saw a big hike in throughput, with QuickBench reporting average random read and write speeds of 275MB/sec and 206MB/sec. Sequential read and write rates were even higher, averaging 343MB/sec and 225MB/sec.
We also tested data tiering by installing a 60GB OCZ mSATA SSD in the small hatch in the 5D's base. Write speeds remained in the same ballpark, but average random and sequential read speeds increased to 311MB/sec and 366MB/sec.
The 5D takes all the strain out of RAID configuration and, with a diskless unit costing a shade over £500, it's good value as well. Mac users looking for a high-performance Thunderbolt DAS appliance should fetch their credit card.