Cost, compatibility are key for VTLs

By Kevin Komiega

It’s no secret that disk-based backup is now a top priority for a large number of enterprises, and virtual tape libraries (VTLs) are emerging as the technology of choice for fixing the broken backup-and-recovery process. But how do end users make a VTL choice in a market flooded with products? If you are planning to evaluate VTL solutions there are several key factors that you should keep in mind before you commit a chunk of your storage budget to any vendor.

Data centers are like snowflakes: No two are exactly the same. Despite that fact, almost every potential VTL user seems to share the same criteria when it comes to evaluating disk-based VTLs. According to users, compatibility (interoperability), performance, and price are the key deciding factors.

Dan Kaplan heads up networking and technical support for Northeast Delta Dental, and in late 2004, he realized that his backup operations were taking up too much of his team’s time. “We are responsible for managing and backing up dental insurance claims, e-mail data, and scanned X-ray images. We were backing up about 1TB of data every night on six DLT80 tape drives, but it became too much to manage,” says Kaplan.

It was a classic case of overnight backups butting heads with the next day’s normal operations, but backup windows were not Northeast Delta Dental’s only concern. Data recovery was equally important. “We need to have a certain number of days’ worth of backups on-site,” Kaplan explains.

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The need for faster backups and quicker file recovery prompted Kap-lan to evaluate VTL solutions from Advanced Digital Information Corp. (ADIC) and Hewlett-Packard. Kaplan ultimately decided to implement ADIC’s Pathlight VX 450 disk-based VTL system.

ADIC’s Pathlight VX 450 is aimed at midrange IT environments where users don’t have the resources to dedicate toward the efficient management of backups. The VX 450 offers 4.2TB of usable disk capacity and 0.5TB-per-hour throughput, which can be dynamically divided among up to 20 virtual drives. It provides integrated tape support for ADIC’s Scalar tape libraries, as well as for libraries from other vendors.

The Pathlight VX 450 provided Kaplan with the speed and access he needed. “I can now store five days’ worth of virtual tape backups on-site and move physical tapes off-site once per week [for archival purposes],” he reports.

Kaplan is not alone. As manager of systems engineering at SkyWest, the parent company of SkyWest Airlines, Josh Ursenbach oversees more than 100 servers spanning three data centers and more than 100 remote sites that must be backed up.

“Our full backups were routinely taking anywhere from 72 to 90 hours to complete,” says Ursenbach. “It was quite cumbersome and frustrating.”

SkyWest needed to boost its backup performance while operating under licensing and cost restrictions. “I needed to work around my licensing and make sure I could support multiple data streams, and the product had to be compatible with my backup software,” says Ursenbach. “The key thing for me was to make sure the product worked with my software without incurring additional cost.”

Ursenbach evaluated VTL systems from various vendors, but ultimately purchased an REO system from Overland Storage. “We looked at a few vendors, but our criteria were pretty high and we didn’t even look at prices until we found the set [of features] we needed. We needed a product that fit in the middle with a lot of disk without a lot of cost,” says Ursenbach.

As with all VTL solutions, Ursenbach experienced immediate performance benefits, but he was not willing to break the bank to speed his backup operations. “We’re getting much better transfer rates than we did with tape, and our backups now take about one-and-a-half hours to complete,” says Ursenbach.

Daniel Doherty, systems operations manager for the Cambridge Health Alliance, implemented backup software from CommVault two years before deciding to evaluate VTL systems, but while his software met his needs it soon became apparent that his hardware wasn’t keeping pace with his requirements.

“Our backup software worked well, but our two LTO tape libraries quickly became overwhelmed as the data outpaced the capabilities of the hardware,” says Doherty. “That’s when we questioned whether we should spend money on a bigger tape library or look at VTLs.”

The Cambridge Health Alliance provides healthcare services to residents of the greater Boston area and, as such, must protect and manage large amounts of patient data to ensure technology does not impede patient care by delaying access to records. Doherty decided to implement a VTL to speed his time to recovery and shrink backup windows in an effort to make sure physicians and staff could access patient data when needed.

The RFP went out to four different VTL vendors with two main considerations. First was full compatibility with the company’s existing software, and second was pricing. Cambridge Health Alliance decided on an S2100-ES2 VTL from Sepaton.

The S2100 was configured as a single tape library with 10 virtual drives and 400 virtual tape slots with 40TB of total capacity and, according to Doherty, there is a significant performance difference between traditional tape backups and the Sepaton VTL. “With the VTL we’re writing just like we’re writing to a tape in 100GB increments. We were doing 24-hour backups and we’ve cut that in half,” he says.

ADIC, Overland, and Sepaton go head-to-head with a slew of vendors in the VTL market, including Bus-Tech, Copan Systems, Data Domain, Diligent Technologies, EMC, FalconStor Software, Hewlett-Packard (via a reseller deal with Sepaton), IBM, Maxxan, Neartek, Network Appliance (see “Net-App joins VTL fray,” p. 1), Quantum, Sun/StorageTek, and Ultera. (FalconStor’s VirtualTape Library technology is resold by a number of vendors, including Copan, EMC, and Maxxan.)

There are a number of differentiating features among VTLs, but the real difference may be in the price tags.

Robert Stevenson, managing director for storage at TheInfoPro research firm, says that VTL pricing is all over the map. “There are some enterprise VTL solutions that start at about $200,000, but we’ve seen people budgeting up to $5 million for several VTL systems in a single implementation,” he says, adding that most enterprise-class VTL solutions fall somewhere between $400,000 and $900,000.

In fact, Stevenson believes some users are delaying VTL purchases because of pricing discrepancies. “We’re finding that some VTL plans are being delayed due to pricing. Some users find VTL prices too high or they cannot separate the cost of disk capacity from the overall VTL solutions,” he says.

Stevenson also believes some users are waiting for more features and functionality to be added to VTL systems. According to preliminary research from TheInfoPro’s most recent user survey, about 40% of storage professionals say that multi-vendor tape emulation is an important factor in VTL purchasing decisions.

TheInfoPro’s research is based on preliminary interviews with approximately 70 storage professionals in the Fortune 1000. The complete results of the research firm’s survey will be revealed in an upcoming report.

This article was originally published on March 01, 2006