Privately-held Data Domain recently rolled out high-end versions of its back-up and recovery system - offerings that exploit compression technology to make backing up data on disk cost competitive as compared with tape, the company says.

By filtering redundant components, the new DD400 appliances and accompanying software can be used to compress data by a factor of 20, the company says.

Because the company's compression algorithm is data-format independent, the back-up images its products create can contain both structured database data and unstructured text files. Typical back-up software such as EMC/Legato NetBackup writes data to the DD400 in an unchanged fashion. As data is stored longer on the appliance, the compression factor will increase because of the amount of redundant data already culled out, Data Domain says.

The offerings, which succeed the 4-year-old company's smaller capacity DD200 appliances, come in three models, ranging in capacity from 15T to 83T bytes. Each model - the DD410, DD430 and DD460 - also has different throughput characteristics. The DD410, for instance, can back up data at 160G byte/hour, compared with the high-end DD460, which can perform at almost twice that - 290G byte/hour.

User notes
Ephraim Baron, senior director for IS&T server operations at EFI in Foster City, California, uses the DD200 and plans to add a DD400 to back up as much as 70T bytes of engineering data.

He said: "“When it comes to backup and recovery, we found that tape has many hidden costs — its slow performance, the time spent handling and sending tapes off-site, as well as the risk that data won't be recoverable. But most disk-based backup systems we looked at were too pricey,”

"We were facing increasing costs of tape backups and the lengthening of the backup window," he added. "The staff I have is pretty senior and I don't want them spending time swapping tapes and getting data packaged to go off-site. Every time I sent management a purchase requisition of $40,000 worth of tape, they cringed."

With the Data Domain appliance, Baron now can keep data on-site longer.

"We are now keeping three to four months of data online that before would have gone off-site each month," he says. "We're essentially backing up the same data, but we aren't doing it all the time."

Data Domain describes its products as capacity-optimised systems or COS. The company states: "Unlike traditional ATA arrays or VTL (virtual tape library) systems, COS systems massively reduce disk storage requirements using high-speed Capacity Optimization technology. COS optimizes storage capacity making retention and replication of backup data extremely cost and bandwidth efficient by providing 20x data reduction."

D2D and VTL Bandaids?
“Backup-to-disk is becoming a best practice in IT, but traditional ATA arrays and VTLs are too expensive for anything more than a local cache-to-tape, so they are just temporary Band-Aids for tape library systems,” said Frank Slootman, CEO of Data Domain. “The DD400 Enterprise Series of COS systems enables customers to implement an end-to-end data protection architecture based on disk and networks, while eliminating the dependency and risk associated with putting tapes on trucks.”

The dig about tapes on trucks is a reference to tape vaulting company Iron Mountain suffering tape loss.

ADIC has data compression facilities with its PathLight VX virtual tape library system. The company stresses that tapes can be taken off-site for vaulting, a security practice not possible with backup to disk servers. Tape loss in such instances is extremely rare. Also, since all good backup SW/HW processes have compression capabilities we can expect disk-based backup systems, including VTLs, to include it.

The DD400 boxes work with IBM/Tivoli Storage Manager, HP OpenView Data Protector and BakBone Software's NetVault, as well as with Veritas NetBackup and Backup Exec, EMC/Legato Networker and CommVault Galaxy.

The DD400 appliances start at $19,000 (about £10,500).

Data Domain has collected $26.3 million in venture funding, and is backed by Greylock, New Enterprise Associates and Sutter Hill Ventures.