A recent survey conducted by Storage magazine provided evidence that disk-to-disk backup is gaining momentum, but there is still some confusion about which disk backup products to buy.
In the 2004 Purchasing Intentions Survey (to be published in the November issue of Storage), 600 users from industries such as government, healthcare and finance were asked a variety of questions about how they are spending their storage dollars. When it comes to disk-to-disk backup, 53% of respondents are increasing their spending. Only 31% of respondents are increasing their use of tape, down from 56% in 2003.
Disk plans interrupted
Yet results from the survey also showed that users have recently been hedging on their disk-to-disk backup plans. Between March and August of this year, the percentage of users employing the three most common types of disk-to-disk backup -- disk-to-disk-to-tape (D2D2T), D2D to tape for archive and disk as file system -- all dropped by approximately 10%. Also worth noting is that the percentage of respondents with no plans to deploy D2D backup rose from 15% in March to 33% in August.
Curtis Preston, vice president of service development at Glasshouse Technologies, Framingham, Mass. said this sudden hesitancy can be chalked up to users still sorting out how to implement disk-to-disk backup. "Two years ago, users had to worry about two things: which tape library to buy and which backup software
Robert Stevenson, technology strategist at the Oldsmar, Fla. operations facility of Nielson Media Research, uses a tiered storage infrastructure to back up 250 TB a month using NetBackup from Veritas Software Corp. Stevenson said he is struggling internally to incorporate more disk into his backup environment. "There are so many ways of doing disk-to-disk backup. The hard part is figuring out which method best serves your customers at the lowest cost."
Right now, Stevenson is evaluating disk staging technology that allows you to create capacity thresholds on secondary disk and move data to tape when it reaches whatever capacity you set. His other option is buying a virtual tape library (VTL), where disk is configured to emulate tape. "VTLs come with the promise of never having to buy more tape drives, which is very appealing," Stevenson said.
Despite the industry buzz created by VTLs, only 10% of respondents from the purchasing intentions survey said they are employing them. "VTLs are a new technology, but I think users are starting to figure out that they bring enough value to justify their cost," said Preston.
Andrew Ferguson, manager, enterprise operations at Brookhaven National Laboratory in Upton, NY, uses a VTL from Sepaton Inc., Southborough, Mass., but isn't willing to bet all the marbles on it just yet. "Our management was leery about VTL, it's new, it's unproven ... We are still cloning to physical tape in some cases for piece of mind."
Adjusting to change
Stevenson agreed that even the slightest change to a backup environment can be a huge adjustment for the operational team. "The word on VTLs is that they can be integrated easily, but you still have to train people how to use them. You're still introducing a new technology to a staff that's not used to a changing backup environment."
Kevin Daly, chief executive officer of disk backup company Avamar Technologies Inc., Irvine, Calif., said one of the main reasons for the hesitancy to deploy D2D backup is that users are asking themselves "if this were the right thing to do, why isn't everyone doing it?"
Daly said that users are emotionally comfortable with tape and still near the front end of the adoption curve for disk-based backup, but sees a "pent-up desire for change" that will speed up adoption once they realize the advantages of disk.
"If the world were in stasis, maybe 'waiting until everyone's doing it' would be an acceptable strategy," said Daly. "However, today's expectations for integrity, speed and scale cannot be met with traditional tape-based technology."
Are the products ready?
A recent poll on SearchStorage.com confirmed that, like Stevenson of Nielsen Media Research, many users are excited about disk-to-disk backup, but are struggling with how to implement it. When asked if the market is ready for D2D backup, approximately 70% of poll respondents answered yes, yet 41% answered no when asked if the products are ready.
Brad Ross, director of information security at Jefferson-Pilot Communications Co., Greensboro, N.C., which runs 24 radio and TV stations across the country, said the initial capital cost of disk-to-disk backup is what's holding them back from implementing the technology.
"We've experimented with D2D internally and it's hands down the way to go ... We can recover our 20 GB Exchange server in 25 minutes from disk instead of four hours from tape." However, he said Jefferson is working out how to manage off-site protection with disk storage, which isn't a removable media like tape.
An independent consultant, who wished to remain anonymous, said that some of the hesitancy to incorporate disk can be blamed on the vendor community. "The vendors are only just starting to do a decent job of educating users about this technology. Users still don't know how to implement it or what the TCO is," he said.