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SANs Fundamentals

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Types of SAN Operating Systems Software and Hardware Components

Recently, for example, EMC Corporation announced that their SAN software that's designed to manage storage devices made by some of its rivals, is a mixed-vendor support that is being done in reaction to pressure from systems administrators1. Users have been pushing for the ability to manage EMC's Symmetrix and Clariion disk arrays along with other storage products and connectivity devices. To start with, disk storage systems made by Compaq Computer, Hewlett-Packard, and Hitachi; and tape devices from Storage Technology have been qualified to work with the new software.

Network switches and other connectivity devices made by companies such as San Jose-based Brocade Communications Systems, and Broomfield, Colorado-based McData Corporation, can also be controlled. An addition to EMC's Enterprise Storage Network (ESN) product line, the new ESN Manager tool provides a single point of control for administrators to use in managing multiple zones of interconnected storage devices.

The development of ESN Manager should scare the hell out of other vendors. EMC is already clearly the storage king. All of a sudden, if EMC actually lives up to what they say and becomes an open systems management provider, they are really a lethal weapon.

EMC hopes to prompt users that don't have its devices now to migrate from single-vendor storage setups to mixed SANs that include Symmetrix and Clariion arrays. People claim EMC is proprietary, but they really are not.

EMC's announcement follows one made recently in which Sun Microsystems said it was teaming up with former rival Brocade. Sun said it would start selling Brocade's Silkworm switches, which act as data traffic directors in a SAN. Brocade in turn announced that it would begin using Sun's Jiro SAN management software with its devices.

EMC's increased spending on software research and development is a sign that the company is genuinely interested in doing more than selling disk arrays. EMC executives want to be more accessible to users who haven't fully committed to Symmetrix and Clariion.

Management tasks supported by ESN Manager include setting limits on which end users can access different devices on a SAN, and configuring logical pathways between various servers and storage subsystems. The software's base price is $24,000 per Symmetrix box, making it a relatively high-end offering in the storage management market.

Sharing Data in a SAN

EMC, for example, has also rolled out software which it claims will unite the competing worlds of NAS and SANs. EMC's HighRoad integrates new software processes into its Celerra File Server and other servers to improve file-sharing capabilities.

The software is aimed at web hosting, image processing and simulation, and modeling applications. It uses separate mechanisms for control actions and data delivery. HighRoad brings together SANs and NAS by routing files and other data directly from the SAN to the user without the intervention of a NAS server.

Customers need all their information to work together. It's about creating one unified infrastructure that builds on the individual and combined strengths of their data and storage networks.

Recently, EMC bought NAS software developer CrosStor, which was working on combining the two storage technologies. EMC also unveiled its latest Clariion IP4700 product, which is aimed at the low-end market dominated by rival Network Appliance. EMC claimed its product will be more reliable than Network Appliance's NAS clusters and cost half the price.

The storage industry has been very busy lately. Coinciding with EMC's announcement, IBM recently pledged to offer a universal storage system that works with all software and hardware systems. Sun Microsystems also announced plans to boost its storage unit by acquiring data storage management software maker High Ground Systems for $500 million.

Tools to Unlock SAN Promise

SAN software tools could bring IT managers closer to the data sharing they thought they were getting when they first bought SANs. People thought when they got a SAN, they'd be getting the ability to share data. And it's true, but they need management tools for that sharing to happen.

SAN resource management starts with knowing what components you have—a process that should be automated. BMC Software in Houston, Texas; Computer Associates International in Islandia, New York; and IBM's Tivoli Systems in Austin, Texas, all claim that their new tools offer varying degrees of autodiscovery capabilities.

Autodiscovery in theory does the same thing that Windows 98 does on your machine at home. Plug in some new equipment, and your system automatically sees it and understands how to manage it.

But, most people who have SANs are still working to put together and monitor all the pieces of the infrastructure. The promise of SANs runs far ahead of what users should expect today. It's rare to see anyone start from a SAN and go straight to application-level management. You have to crawl before you walk, and there's still some crawling to be done to get to interoperability and management at the component level. Underlying the success of the SAN concept is the key assumption that standards will be developed.

In an International Data Corporation (IDC) survey in 2000, more than half of IT managers responding indicated that they were considering purchasing a SAN. But 80% indicated that open standards are critical for any SAN implementation they would consider. See Chapter 3, "Standards," for more information.

We're still a long way off from having universal standards in SANs. However, SANs are following a path similar to what happened in the LAN environment.

The Case for SAN Hardware

Storage hardware is about as exciting to most IT and business managers as watching pet rocks sunbathe. But it's rapidly becoming the single most important element of e-business innovation. Just look at your company's e-business infrastructure.

There's only one proprietary component: the enterprise customer data. Never put that at risk in terms of availability, security, ability to scale customer relationship management (CRM) systems, speed of access, backup and archiving, or server consolidation.

Almost every other platform component is now a commodity; a company can substitute one excellent vendor's products for another's—low-end and mid-range servers, PCs, and Internet hosting services, for example. Or a company has some wiggle room: It can call in systems integrators and C++/Java wizards, or build front-end links to legacy systems. This is by no means easy, but none of these areas is the giant bottleneck that storage is now.

Here's the problem for IT: For decades, storage has been handled as just an add-on to IT strategy and as JBOD—storage professionals' acronym for just a bunch of disks. Whoever handles JBOD purchases says, "Your data warehouse is exploding again? Buy two clusters and call back next month."

Even the NAS versus SAN debates about how to best manage networked storage are typically handled in nonbusiness terms, centering on such concerns as response times and operating costs. In IT, there's often a wide gap in thought and knowledge between network and storage professionals.

Try asking your best telecommunications experts about Fibre Channel or backup and archiving. Then talk to the storage people about IP-based SANs. In most instances, you'll see blank stares. Look at the network architecture plans. See if you can find the storage architecture plans. Good luck. Then look at your company's many CRM activities and see if there's any discussion of their implications for storage beyond JBOD and aspirin. Again, good luck.

IT needs to raise the strategic discussion of storage in the same way, and to the same degree, that telecommunications moved in the 1990s from cables and boxes to e-business architecture; and in the same way that databases have moved from software to CRM. Storage vendors and buyers need to build an entirely new dialogue.

In the JBOD world, vendors are box salespeople, and IT organizations are box buyers. Both are in a commodity transaction, not partners in enterprise storage strategy. The JBOD suppliers come in with feature lists, prices, and service promises. That's fine for semicommodities such as low-end servers, PCs, and Internet hosting. But, it's inappropriate when the discussion is about the architecture for the firm's customer data resources or its e-business strategy and platform architecture—and recognizing the importance of never putting either at risk.

As the storage issue rises above JBOD, IT must redefine the vendor dialogue, and vice versa. Will EMC's powerful sales force and aggressive selling be the basis for your company's dialogue? Will Hitachi Data Systems' increasing dominance in pure technology and product leadership translate into architecture leadership? Will Sun be able to turn its e-business server strengths into comparable networked storage strengths? Until a year ago, $3 of sales in servers meant $1 of storage sales for Sun.

Now, it's the reverse. Dell, Compaq, Network Storage Solutions and Hewlett-Packard (which is mostly Hitachi with a different logo) all have good boxes.

Which will be the platform partner? That would be the next IT e-business agenda. Which would you choose? Probably Hitachi, because if your firm's customer data is your proprietary business edge, you would want the best hardware. But, don't take anyone's word for it. IT professionals must have their own opinions, shaped in their companies' best interests.

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