Drobo&39's storage devices are expanding with a larger and now-rackmountable 12-drive configuration.

Nigel Tufnel's amp goes up to 11, but Drobo's newest storage system outdoes the Spinal Tap guitarist with a new 12-drive model.

The new Drobo Elite B1200i, geared for small businesses, is a central storage system that connects to people's computers via the iSCSI technology for building a storage area network. It's matched by a similar 8-bay iSCSI model, the B800i, and a related network-attached file storage model, the B800fs.

The models are a new high-water mark for Drobo, a company that got its start with much smaller desktop storage systems that attached to personal computers but that has been gradually ascending to more demanding tiers of the storage industry.

Universal across the products is Drobo's core feature, a data protection technology that lets customers mix and match any size capacity. That's a significant change from conventional RAID (redundant array of inexpensive disks) storage arrays, which need matched drives. Like conventional RAID, Drobo storage systems can rebuild lost data in the event of a hard-drive failure. They're also designed to expand easily and automatically when people add new drives or swap out old ones.

A new feature coming with the new models is the ability to accommodate 3TB drives, not just 2TB models as before, Chief Executive Tom Buiocchi told CNET. That increases the net capacity substantially, he said.

"A very rough calculation suggests the 8-bay products will show about 12.5TB and 11TB with 1- and 2-drive redundancy [respectively]," and the 12-bay model should be about 50 percent more on top of that, he said.

The 8-bay models start at $2,199 with no drives and are available now. Drobo will sell a 12-bay model with 12 1TB drives for $9,999 when it goes on sale in the second quarter.

The new models accommodate either SATA or SAS hard drives or SSD flash memory drives. Also new is management software geared for small businesses and automated thin provisioning, in which storage volumes are automatically resized according to need so that storage capacity isn't wasted. Finally, the 12-bay model has new redundant hardware to protect against failure, in the form of dual hot-swappable power supplies and three gigabit Ethernet ports for iSCSI.