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The pairing of server blades and storage seems to be all the rage these days.
IBM, for one, recently released a few products pairing the two technologies: an embedded switch module co-developed by McData and QLogic; the LS20 blade with iSCSI capabilities; and a SANRAD blade version of its Switch-V iSCSI SAN switch based on IBM's BladeCenter Open Specification.
Meanwhile, HP's BL20p and BL35p blades have been released to facilitate blade and Fibre Channel integration, and HP is also pushing the storage, virtualization, networking and management capabilities of its HP BladeSystem.
"HP server blades have a 45 percent attach rate to Fibre Channel," says Mark Potter, vice president of HP's BladeSystem Division. "The attach rate to HP blade enclosures hovers in the 65 percent to 70 percent range."
According to HP, then, about half of all server blades shipped have an HBA built specifically for blades known as a mezzanine card. In terms of sheer numbers, Dell'Oro Group states that about 125,000 mezzanine cards (most with two ports per unit) shipped in 2004, with about double that amount expected this year. That's a big portion of the 600,000-plus blade servers that will be shipped this year a number that is growing at a rate of 50 percent per year.
"Anyone with lots of data needs high-density compute power," says analyst Tam Dell'Oro. "Blades and FC make a very good combination."
Perhaps the biggest reason for the blade-storage marriage is economics. It is cheaper to attach a SAN to blades than via rack-optimized servers. For example, a dual port FC HBA for HP server blades is $599 versus a standard PCI-X FC HBA that runs at $2,450. For a customer deploying 16 servers, the savings from the difference in HBA costs alone is almost $30,000.
Those numbers don't take into account the fact that blade/SAN architectures offer consolidation and savings from integration and elimination of traditionally costly components such as small form-factor pluggables (SFPs) and Fibre Channel cables. In the same 16-server scenario, the reduction in SFPs and cables equates to about $9,600.
By embedding SAN switching in blades using technology from the likes of Brocade and McData, Potter says HP can offer price points lower than traditional SAN switches. These embedded devices leverage existing infrastructure for power and cooling while integrating SAN-connected blades into existing storage fabrics. Most importantly, the devices deploy exactly the same way a 1u branded switch does from a management standpoint, so there are no differences for customers managing SAN connections.
"We will continue to drive aggressive pricing for Fibre Channel mezzanine cards, and have begun to seriously look at ways to drive lower costs for embedded SAN switches," says Potter.
Tom Clark, McData's director of solutions and technologies, voices a similar view.
"The main economic driver behind blade server technology is cost reduction in server platform management," says Clark. "Blade servers and blade SAN switches enable the consolidation of both server and SAN assets in more easily managed configurations."
While HP stresses the cost benefits, IBM focuses more on simplifying the infrastructure to support a high level of information sharing and business flexibility. This means physically consolidating storage environments and reducing the number of devices. Case in point: IBM now offers the first 4Gb SAN solutions for blade servers (developed in conjunction with QLogic, McData and Brocade).
"As our customers' budgets continue to be under pressure, we are very aware there is an increasing need to do more with less money and fewer people," says Nancy Reaves, worldwide product marketing manager for IBM BladeCenter. "Therefore, we need to continue to integrate, simplify and increase the manageability of servers, storage and networking."
HP agrees with the goal of simplification via blades. It sees blades as part of a modular, integrated system of server, storage, and network, managed from a single console. In straightforward terms, integration and modularity cut costs. Virtualization improves utilization and management. By virtualizing at the server, storage, network and processor level, the entire infrastructure can be combined into one resource pool. Blades are seen as catalyst in this evolution.
"We cannot continue to simply look at the hardware angle and take a server-center, storage-centric view of the world," says Potter. "Simplification through integration in a bladed environment is what will change it all."
Who is leading the way in hooking up a whole bunch of blades into a storage network? Potter states that enterprise data center scenarios, as well as key vertical targets (financial, scientific, service providers, etc.) tend to dominate. But usage is widening into a broader segment of the market as the technology matures.
"Attaching blades to a SAN broadens their usability," says John Enck, an analyst at Gartner Group. "You can store blade images on the SAN and provision (or re-provision) blades on the fly to address failures or workload demands."
Most vendors tout blades as the answer to just about everything. Tom Buiocchi, Brocade's vice president of worldwide marketing, notes that the expansion of bladed server computing was fueled by embedding SAN switches into blade servers. To his mind, this technology will be harnessed by many to forward their consolidation initiatives.
"Organizations that want to consolidate and centralize their IT resources have been turning to bladed servers," says Buiocchi. "To maximize the benefits of this technology efficient space utilization, high availability, and the flexibility to add resources as needed an increasing number of chassis have been equipped with integrated SAN switch modules.
In 2005, for example, Brocade added 4Gbps switches for blade servers from IBM and HP, as well as a 2Gb embedded SAN module for blade servers from Dell.
Clark sees bladed storage operating across the entire market range. For higher performance requirements, he believes that embedded FC switch blades can provide the same robust, multi-gigabit throughput and availability established by conventional SANs. For lower performance requirements, he also sees blades functioning alongside iSCSI for less mission-critical applications. He admits, however, that blades may not be right in all cases.
"Blade technology may not be suitable for very high-end applications," says Clark.
Enck cautions further that blade/FC integration is not for the faint of heart. It requires a degree of sophistication in the IT organization.
"Basically, those organizations that have already invested in SAN technology are attracted to this solution," says Enck. "I rarely see someone implement blades and FC and SANs all at once."
Just how pervasive can bladed storage become? IDC expects the market to reach $8 billion by 2008. Dell'Oro Group places IBM ahead of HP, with Dell playing catch up from a long way back. The market potential also signals a bonanza for QLogic and Emulex as manufacturers of mezzanine cards and their related chips.
HP's Potter considers blades the salvation of FC. The protocol has been under attack for the last year or two from lower-priced iSCSI technology. Some analysts have even projected that new interconnect technologies would displace Fibre Channel because of its cost.
"The fact is that FC isn't that expensive in the BladeSystem model," says Potter. "In terms of price or performance, Fibre Channel looks to remain unchallenged in the near term, especially when you consider the maturation of management tools and legacy installed base of Fibre Channel targets."
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