Fed up with slow tape backup systems and under pressure by regulators and auditors to keep data online and readily available, large and midsize businesses are making disk-to-disk backup technology a top priority in their data centers this year.

More than 75% of 150 large companies recently surveyed by TheInfoPro, a New York-based independent research firm, said disk-to-disk backup technology is being used in their data centers; this compares to 67% who were implementing it a year ago.

Still, in the most recent survey, only about a third said they are using virtual tape libraries (VTL), a form of disk-to-disk backup that essentially uses disk arrays to mimic tape for server backup jobs.

One in four IT managers surveyed said they believe poor archiving practices are a key reason for unchecked data growth. The average company has 250TB of active storage space dedicated to archive-related content. Moreover, the survey found that archive capacity among companies is expected to grow by 52% by the end of this year.

Sean O'Mahoney, manager of client/server computing at Norton Healthcare, which has more than 2,000 physicians, rolled out three disk-to-disk backup systems over the past year. It helped the organization deal with a 50% year-over-year archival data growth rate that pushed the backup window to 20 hours a day.

Since connecting the health care firm's Picture Archiving and Communications System to an EMC Clariion Disk Library 710 array and Clariion Disk Library 4100 array, Norton's backup window has been more than halved -- to eight hours a day. O'Mahoney also plugged his company's financial systems into an EMC Centera disk array, which is a WORM permanent archive system.

In all, Norton Healthcare has 200TB of capacity dedicated to disk-to-disk backup, the vast majority of which is used for storing radiological images such as X-rays, which do not lend themselves easily to compression.

Besides shrinking its backup window with disk-to-disk technology, the organization also improved data-restore times by as much as 75%.

It used to take four days to retrieve data from tape because Norton's AIT-2 tape drives have a maximum throughput of 6MB/sec., compared to the Clariion disk array's 60MB/sec. rate. "The speed of the media is vital," O'Mahoney said.

TheInfoPro's survey, released in May, revealed that IT managers consider backup activities among the most time-consuming, adding that staffing remains flat and budgetary pressure to cut costs is at an all-time high.

A study by Gartner earlier this year predicted that by 2010, disk and not tape will be the primary medium for data recovery and that by 2011, the ability to take continuous snapshots of data will be an embedded function in backup and data replication software and will no longer be a separate feature.

Currently, only 17% of companies have deployed continuous data protection, according to TheInfoPro's survey.

"The need for high-performance online recovery of data, combined with the availability of low-cost disk arrays, has influenced enterprises and small and midsize businesses to adopt a disk-based approach for backup and recovery," Dave Russell, author of Gartner's disk-based storage report, wrote.

Tony Asaro, an analyst at the Enterprise Strategy Group Inc. in Milford, Mass., said the driving force behind disk-to-disk backup boom is a combination of massive data growth, which is expanding backup windows, and legal and auditing requirements that force firms to keep records online and accessible for longer periods.