Data Robotics DroboElite review

Data Robotics' Drobo, launched in 2008, was a clever storage solution that allowed hard disks of different makes and sizes to be used in the same array. The DroboElite takes the same smart concept, adds even more features and extends them into IP SANs.

This smartly designed and quiet desktop box is a pure iSCSI appliance that supports up to eight hot-swap SATA hard disks. Uniquely, the Drobo family can mix and match drives of different capacities, allow failed drives to be replaced on the fly and support capacity upgrades with larger drives as required.

As drives are plugged in they're automatically added to a single virtual storage pool, where the appliance configures redundancy at the block level. The DroboElite goes further as its BeyondRAID technology offers even more useful features.

Dual parity protection is available at the click of a button. The appliance starts with single parity protection, but you can turn dual parity on as the fancy takes you. If you change your mind or need some extra space you can go back to single parity at any time, which no normal storage appliance can do.

The DroboElite supports 255 smart volumes that can each be up to 16TB in size. Thin provisioning comes as standard and allows virtual volumes to occupy a significantly smaller chunk of physical space, but appear much larger to the applications using it.

There's a pair of Gigabit iSCSI data ports. You start with a USB connection and configure the IP addresses of the data ports from the Dashboard utility. You can then free the appliance from its USB connection as the utility will now connect to it over the network.

Volumes are easy to create. You pick from 1, 2, 4, 8 or 16TB sizes and opt for CHAP authentication if required. Only the server where a volume was created can access it, and other Dashboards will display a padlock icon next to it.

There's nothing to do with the iSCSI initiator as the Dashboard creates a persistent connection to the target and presents the new volume ready for use. It also employs an extra target for Dashboard communication, which shows in the Disk Management window as a bogus drive, but you can ignore it.

For testing, we placed each data port on separate Gigabit switches and subnets, but you can keep them together. Either way, once you've set up their addresses, leave them alone as the appliance and the Dashboard can get upset if you change any of them later on.

General performance is good. With one server running Iometer, we saw a fast raw read throughput of 105MB/sec. With a server connected to each data port we saw some contention for appliance resources, with Iometer reporting cumulative read speeds of around 135MB/sec.

When we reviewed the original Drobo appliance we weren't impressed with its limited performance and basic file-sharing features, but the DroboElite is a different beast altogether. It takes the pain out of IP SAN setup, overall performance is good and the unique BeyondRAID technology offers a set of enterprise-level storage management features.

Author: Dave Mitchell