Who needs SAN virtualization?


According to Data Storage Technologies (Ridgewood, NJ) president Richard Lee, there are a number of value propositions to "virtualizing" a storage area network (SAN), including lower management costs, less complexity, and higher return on investment.

"Most virtualization investments pay back in the first two years," he says. "So, even though there is a significant upfront investment, when you analyze the potential cost savings of virtualizing your SAN, it becomes a very simple decision."

"It's not a question of whether users need virtualization, but whether they have the resources to implement the technology," says Steve Duplessie, an analyst with the Enterprise Storage Group in Milford, MA.

Weak economic conditions and high virtualization prices have stalled end-user adoption. "We're seeing a lot of hype from vendors, but no discernable pulse from the user community," says John Webster, a senior analyst with Nashua, NH-based Illuminata.

"The economy isn't helping," says Duplessie. "A user facing budget cuts would be nuts to invest in any new technology right now." The only deals being made today are those that have been in the works for months or where there is a "screaming need" for virtualization, he says.

"There is potentially the need among 100% of SAN users for virtualization, but today most products are really geared to the middle of the enterprise space on up," says Lee. "Those users have the most acute problems and, therefore, are the easiest to identify in terms of opportunity."

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Duplessie says the main reason users are turning to virtualization is for applications like snapshot, mirroring, and replication-not just disk pooling. Take a company that needs data replication in an EMC environment, he says. "They have some EMC boxes and want to perform those functions. They can either buy another EMC box or a virtualization product [for a fraction of the price] that [incidentally] can be used with any vendor's storage."

Similar benefits apply to network-attached storage (NAS) infrastructures. "Virtualization is just as critical on a file level as it is on a block level," says Lee. "One of the problems of most NAS appliances today is that when you get beyond the capacity of the appliance, that's it."

Additional NAS appliances, or add-on chassis, increase storage capacity, not storage flexibility, says Lee. "You haven't created a storage pool, just a bunch of storage devices that look like logical units, so when you run out of logical units, you run out of storage flexibility." Virtualization tools can provide this flexibility.

So, is it really a question of "Who needs virtualization?" Not really. "In terms of users planning for the future, they should all embrace virtualization as part of their strategy," says Lee.

Analysts expect virtualization prices to drop over the next 12 to 18 months as the market matures and consolidates. This should deepen the technology's reach into lower-end market segments.

One vendor's experience

Alexandria, VA-based Plumbers & Pipefitters National Pension Fund manages more than $4.5 billion in retirement funds for more than 200,000 union members. The company implemented a storage area network (SAN) and virtualization scheme nearly two years ago.

"We were scared to death," says Bill Manning, IT director for the fund. "There wasn't a whole lot of success out there then [with SANs or virtualization], so I really didn't know which products were going to take the lead."

Manning says underlying problems with RAID capacity and performance prompted him to investigate SANs and virtualization. "I was dealing with having to redo my RAID every six months," he explains. "What intrigued me was the possibility of being able to expand volumes at will with virtualization."

Why DataCore's SANsymphony virtualization engine? Says Manning: "DataCore presented the idea of not being locked into [any particular vendor's] solution." The fund also considered virtualization products from IBM and Veritas.

Manning reports no problems with the product's scalability and says he will implement two more SANs this fiscal year-one for the company's business-critical Unix applications and another for off-site disaster recovery. He says he also plans to take advantage of some of SANsymphony's newest features (e.g., Asynchronous Internet Mirroring and snapshot) in these environments.

This article was originally published on August 01, 2001