Everyone Into the Virtualization Pool

The major storage vendors are now well into the process of solidifying their positions on the SAN- virtualization bandwagon. Consider EMC, which is getting ready to roll out its newly christened Invista platform, the long-awaited enterprise-virtualization engine previously known as Storage Router. Or Network Appliance, which recently renamed all of its arrays that pool storage into a product category called VSeries. Then there's IBM, which has shipped more than 1,000 of its SAN Virtual Controller (SVC) appliances. Meanwhile, Hitachi Data Systems is well into the first year of shipping its new high-end storage array, called TagmaStore.

But if you and your customers are not in the planning process of deploying storage-virtualization solutions, don't despair. Despite a barrage of new storage-virtualization products, a major shift in managing data is involved. To boot, there are various architectural approaches to consider. Bottom line: That all takes time.

"There's a lot of confusion in the market about the different vendors' approaches to virtualization," says Sandi Scullen, EDS' executive director of storage services.

"We see this as a year of tire-kicking for storage virtualization," adds Dennis Hoffman, EMC's vice president of software marketing.

Early-Adopter Phase

Many experts say virtualization will become a key enabler of SAN consolidation and more simplified storage-systems management. The need for it will increase, some experts say, as companies deploy content-addressable storage and develop information life-cycle management (ILM) strategies that are best implemented using tiered storage. Using a storage-virtualization engine will allow customers to rearchitect their monolithic methods of storing data where a database or e-mail system has its own respective SAN.

Virtualizing storage will help customers move away from managing specific devices, instead allowing them to focus on administering pools of data and, in a perfect world, manage storage on multiple networks.

"Everybody is interested in trying to make the server [and SAN] stack skinnier," says Robert Keahey, EDS' director of technology strategy and architecture. "As we go forward, with the advent of intelligent SAN switches, we are starting to see a movement of intelligence out into that switch."

Of course, it's not a perfect world, and storage virtualization is still in the early-adopter phase. Those customers that are implementing storage virtualization are typically doing so within pockets of their organizations, and generally in nonmission-critical environments.

"If you talk about the biggest data centers, they are very reluctant to put anything on the network," says Mike Kahn, an analyst at the Clipper Group. "They are risking their daily operations to do that. So they go about it in a very slow, multiyear testing mode."

Jockeying For Position

While smaller vendors, such as DataCore, FalconStore and StoreAge Networking Technologies, are early providers of storage-virtualization software and appliances, tier-one system vendors are now plugging storage virtualization in a big way. IBM is quick to point out that 75 percent of its SVC sales have gone through partners, while EMC's Invista initially will be a direct play (though at least one partner tells VARBusiness that he expects to be involved in a pilot early on).

In fact, with the launch of Invista, there's no shortage of competitive positioning. "If you think about the large enterprise marketplace, the last thing they want to do is put a technology into their storage environment that's unproven, unstable and immature," says Roger Wofford, manager of storage software products in IBM's server group.

Wofford's criticism is that EMC is targeting the very high end with its Invista product, with plans to scale down over time. In contrast, IBM's SVC is targeted at the midrange, with plans to scale up over time. "It seems to be almost contradictory to target large enterprises...where you have the most conservative users," he says.

EMC doesn't see it that way. "Some of our competitors have taken the tactic of trying to start with the midmarket and move up," Hoffman says. "We've never found that to be a particularly successful way to build an architecture. We prefer to architect for the high-end solution, and know that we can cover the scalability and data-integrity demands of the enterprise and scale down."

Getting past the marketing rhetoric, both arguments have merit, according to industry experts. But, suffice to say, solution providers who see opportunity to help customers virtualize their SANs will have to wait some time for EMC to broaden Invista into the channel.

"I think the technology will be available in the channel once people get comfortable with it and it gets proven out," Hoffman admits.

In Or Out of Band?

The manner in which data is virtualized is another consideration. Invista will use a "split-path" architecture, where the data stream is routed through an embedded switch, provided by Brocade or Cisco initially, or McData next year. Among those currently supported are Brocade's Silkworm 7420 multiprotocol storage router and new line cards introduced for Cisco's MDS Series 9000 switches (McData will release its own interface early next year).

In the case of Cisco, which is seen as a relative newcomer to SAN switching, the line card would go into the chassis, which has Fibre Channel ports and an embedded virtualization engine that runs the Invista application, says Rajeev Bhardwaj, a Cisco senior product manager. With Invista, customers can logically pool or combine storage arrays together and centrally manage how data is provisioned.

So, while Invista runs within the switch, SVC connects to a switch. Which approach is the way to go? Depends. The split-path (or out-of-band approach) is more disruptive than the in-band approach to virtualization, though both introduce major changes to data management. That's why many customers are likely to remain on the sidelines for some time. But Enterprise Strategy Group analyst Nancy Hurly says, at some point, customers will be pushed to look at virtualization more closely.

"In the long run," she says, "once you start building out new SANs and all switches start coming off lease, we expect there's no reason they wouldn't just immediately put intelligence in the fabric on the switch."

Much of the decision of whether to virtualize the network will rest on the volatility of the data, Clipper Group's Kahn adds. "There's a lot to be said for putting it in the network," he says. "At the end of the day, it really depends on how much data you have to move and how much data you've got to change."