Overview of the Server Clusters Design Process

Applies To: Windows Server 2003, Windows Server 2003 R2, Windows Server 2003 with SP1, Windows Server 2003 with SP2

Mission-critical applications, such as corporate databases and e-mail, must reside on systems that are designed for high availability and scalability. Deploying server clusters with the Microsoft® Windows® Server 2003, Enterprise Edition or the Windows® Server 2003, Datacenter Edition operating system minimizes the amount of planned and unplanned server downtime. Server clusters can benefit your organization if:

  • Your users depend on regular access to mission-critical data and applications to do their jobs.

  • Your organization has established a limit on the amount of planned or unplanned service downtime that you can sustain.

  • The cost of the additional hardware that server clusters require is less than the cost of having mission-critical data and applications offline during a failure.

Windows Server 2003 provides two different clustering technologies: server clusters (discussed in this chapter) and Network Load Balancing. An overview of these cluster solutions is provided in "Planning for High Availability and Scalability" in this book. For more information about Network Load Balancing, see "Designing Network Load Balancing" and "Deploying Network Load Balancing" in this book. Note that this chapter focuses on using server clusters to make applications highly available. For information about using server clusters with resources such as file and print services, see "Designing and Deploying Print Servers" and "Designing and Deploying File Servers" in this book.

A third clustering technology, Component Load Balancing (CLB), is available in Microsoft® Application Center 2000 but not in Windows Server 2003. CLB clusters enable COM+ applications to be distributed across multiple servers. For more information about CLB, see the documentation for Microsoft Application Center 2000.

If your business is considering server clusters to provide increased availability for one or more applications, and you plan to use Windows Server 2003 — either Enterprise Edition or Datacenter Edition — this chapter will help you evaluate, design, and implement a server cluster compatible with those applications. If you are already running server clusters on Windows NT 4.0 or Windows 2000, this chapter helps you prepare to upgrade those clusters to Windows Server 2003.