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SANs Fundamentals

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The Value of Information

Finally, people have always placed a high value on information and knowledge. From the first cuneiform characters pressed into clay tablets to today's petabytes of data held on magnetic media, information has been protected and valued. Because it was valuable and hard to acquire or store, information was kept in the hands of a few experts for thousands of years. It was only with the advent of printing in the fifteenth century that an information explosion began that led to thriving new nations and burgeoning societies, such as those of North America and Europe.

As information and knowledge became more available from 1500 onwards, it became essential to learn to read. At first, only the rich and privileged had the time and the means to learn to read and access new information. However, as the need for skilled labor to build and maintain societies evolved, governments realized that an educated workforce was essential to national prosperity. An association of schools, libraries, vocational training establishments, and colleges appeared almost overnight in the newly industrialized countries, and created a knowledge and information system that catapulted its developers into the twentieth century, laying the foundation for today's astonishingly successful, connected world.

The lesson learned from these information-based developments is that sharing knowledge and data makes a society and its individuals and organizations better able to communicate and work together for mutual benefit. Just as money is much more useful when it is invested and in circulation, so is information a much more useful tool and broader resource when it is shared. The opening months of the twenty-first century show global business poised to benefit from shared electronic information in the same way that society was just beginning to see the real advantages of universal education around 1900.

The Business Information Landscape Today

The profusion of storage technology advances available now or soon to come to market is guaranteed to confuse IT professionals and leave business executives bewildered. While the objective is simple (to provide the best possible information systems), the method and technologies to be used are anything but simple.

For example, Tivoli Systems has refined the various available components into what it calls the Information Grid3. This combination of components consists of: SAN topology; new technologies, such as fiber channel hubs; switches and interconnects; new disk and tape technologies; and resource and data sharing techniques. The Information Grid promises extraordinary opportunities if organizations can deal with the inherent challenges.

Today's business information environment still consists largely of islands of information within an organization that have limited contact with each other and very little in the way of effective links and conduits across which information and data can flow to the people who need them. These islands may be in the form of large existing corporate systems that are based on mainframe architecture. They may be simple LANs that link the PCs or Microsoft Windows NT systems of a branch office or remote facility, or perhaps UNIX technology-based departmental systems in engineering, research, or accounting functions. Whatever form information takes, it has always been difficult, if not impossible, to share—and it is even more difficult to achieve the powerful benefits of harnessing information into a single, seamless environment.

Preparing for Storage Area Networking

By 2002, most experts expect the first complete implementations of SANs to be in place and running successfully (see Chapter 2, "Types of SAN Technology"). A large number of IT vendors are actively pursuing this goal. However, for the IT user community, deciding which company or companies to form successful relationships with will be critical.

SAN technology is part of the larger challenge of establishing a full storage networking management strategy. Careful consideration should be given to choosing a vendor or partner that is capable of implementing the full range of benefits of storage management. These benefits include:

  • 24 × 7 × 365 availability
  • Scalability
  • Data sharing across different architectures
  • Storage access at all times and from all locations
  • Better performance
  • Cost reductions
  • Improved security
  • Significantly better data protection
  • Verifiable and consistent data integrity
  • Easy-to-use, consistent data management tools3

For example, Tivoli, in partnership with many of the leading storage management and SAN vendors, has developed and planned for the technology required to ensure successful, full implementation of SANs. Tivoli is developing new products that will be essential to exploit the Information Grid in all its capabilities. As highly IT-dependent companies develop increased competitive advantage through adept management of their information and data, they are turning to Information Integrity Initiatives (checking the reliability and quality of information) to provide the structure for their storage strategies. The key areas where installations must be prepared for SAN implementation and also for storage management fulfillment are:

  • Application management
  • Data management
  • Resource management
  • Network management
  • Element management

Application Management

Application management is a vital component of the relationship between business systems and IT capabilities. It is also the obvious point at which strategic business goals can be furthered by the skillful implementation of enterprise applications. However, there are some considerations that affect application management in an enterprise environment. Large-scale business applications are usually very complex, involve custom and off-the-shelf software, and are linked to the three most common architectures—mainframe, open systems, and desktop environments. The picture is further complicated because all of these enterprise applications are essential to the financial health of a business.

Data Management

Data is the lifeblood of business. Just as governments and business discovered that money was an engine for economic growth only when it was available, so are businesses rapidly realizing that data assets are many times more effective and valuable when widely accessible. For example, in the Tivoli Information Grid, data management assures that data is available and accessible for applications; that data meets the specifications for application use; and that data is recoverable in case of a failure. Data management functions with all types of storage, whether remote, centralized, or removable. Data management functions at all levels, from large system servers to desktops.

Resource Management

Business executives who are intimately involved with IT are sometimes puzzled by decreases in the unit cost of processors, storage, communication, and the increased total cost of IT. Storage management, in general, and storage area networking, in particular, should provide some relief from this conundrum by managing pooled, fixed disk, and tape resources, as well as all removable media and the implementation of just-in-time storage management.

Network Management

Network management is probably the most critical part of the SAN and storage management challenge, in terms of the burgeoning e-commerce market. LAN and WAN resources already form part of every large enterprise and are familiar to all business executives. SANs are the logical extension of these proven networks and bring the same, or greater, value to the companies that deploy them. SANs will be as critical to business success in the future as LANs and WANs are today. SAN capabilities in the network management space include predictive capacity planning, connectivity mapping, performance, and error mapping, largely in the Fibre Channel area.

Element Management

Element management is the most detailed of the layers of storage management, and is usually overlooked by business planning. It involves the management and interaction of individual hardware elements within the SAN from different storage manufacturers, which enables SANs to integrate different storage architectures from different manufacturers.

The Challenge of Implementing SAN Technology

Although rapid strides have been made in SAN technology, and a great deal of implementation work is underway, knowledgeable IT watchers do not expect to see genuine SAN solutions up and running until the last quarter of 2002. To achieve a genuine SAN solution, the following are the basic conditions that a network must meet:

  • Any-to-any interconnection of servers and storage systems

  • Speed of recovery and magnitude of data loss after disaster

  • Universal access and sharing of resources

  • Centralized resource management

  • Excellent information protection and disaster tolerance

  • High levels of security and data integrity in system architectures

  • Massive scalability to cope with the future explosive growth in information technology deployment3

SAN is not the ultimate cure for the challenges executives face due to the exponential growth of e-business and corresponding requirements for high storage capacity and data protection. However, SAN is an essential component in the future of business IT. Terms like multivendor tape resource sharing and LAN-free data transfer over established IP and Fibre Channel networks will soon become commonplace, as companies encounter the challenge of using SAN technology to provide business advantage.

Implementing SAN environments will consume many resources in the coming years. The selection of trading partners, such as IBM, Tivoli, or one of the other experienced technology creation and deployment companies, will be an essential prerequisite for success. As further enhancements (such as disk and data sharing) become common, the more important it will be to have a broad spectrum of experience and capability with technology integration.

The essential characteristics to look for in a SAN vendor or trading partner are not found in any one capability. It is immaterial whether that capability is in volume mapping, tape management software, or any other point. The key criteria for selecting a company to build a SAN or storage network management system is its ability to help make the best-of-breed technologies from all sources work together for the best total system. Most of the proven, smaller vendors have excellent products that can be considered at the element-management stage of creating a SAN.

The Storage Networking Management Vision

The future vision of storage area networking management is one that exploits both the Information Grid and customers to create storage solutions and networks that build business advantage (see Chapter 19, "SAN Solutions for Consideration"). By taking the best technologies and combining them with those from various integrators, it will be possible to assemble e-business, manufacturing, retail, banking, healthcare, or any other type of business IT solution that an enterprise will need. Islands of data will become transformed into a united resource that shares information and multiplies its worth to each organization. Storage area networks will vault their users through the twenty-first century by enabling the sharing of data and information, and multiplying their worth far beyond their value as discrete resources.

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