Microsoft Corporation
April 1997
Clustering technology enables you to connect a group of servers in order to enhance data availability, server manageability, and performance. Regardless of how many servers are connected in a cluster, a workstation will treat it as if the cluster were a single server. This benefits you in three ways:
According to a FIND/SVP Strategic Research Division Report (1992) it is estimated that system downtime costs U.S. businesses $4.0 billion per year. The average downtime event results in a $140,000 loss in the retail industry and a $450,000 loss in the securities industry. Clustering promises to minimize downtime by providing an architecture that keeps systems running in the event of a single system failure.
"Wolfpack" is the code-name for the clustering technology being developed by Microsoft® for Windows NT® Server. The Wolfpack software is written by Microsoft, but it incorporates algorithms and expertise provided by Microsoft’s core partners in the Wolfpack initiative: Compaq Computer Corporation, Digital Equipment Corporation, Hewlett-Packard Company, IBM Corporation, Intel Corporation, NCR Corporation, Tandem Computers, Inc. These core partners represent the key pioneers and innovators in cluster technology, and Wolfpack software has greatly benefited from their collective experience.
Existing clustering solutions are complex, difficult to configure, and were built using expensive proprietary hardware. Microsoft, in conjunction with its industry partners, intends to bring the benefits of clustering technology to the mainstream of client/server computing by developing clustering technology for Windows NT Server based on open specifications, industry-standard hardware, and the ease-of-use customers have come to expect from Microsoft products.
No. Wolfpack complements other high-availability techniques such as data mirroring, RAID disk protection, uninterruptible power supplies, and duplicated hardware such as fans and network interface cards. The availability role of Wolfpack is to automatically restore user access to data and services following the failure of individual applications or servers. Wolfpack and other high-availability technology should be used in concert with prudent IT administration procedures for data backup and disaster-site recovery to ensure continuous availability of mission-critical IT resources.
Microsoft is releasing Wolfpack in a series of carefully controlled, well-tested phases. Phase 1, available in the summer of 1997, will primarily improve availability and manageability by providing support for 2-node clusters. Phase 2, available in 1998, will enable more than two servers to be connected together for even higher performance and easy, cost-effective scalability.
The following "Early Adopter" companies are providing expertise plus test and support resources during the development of Wolfpack Phase 1: Compaq Computer Corporation, Digital Equipment Corporation, Hewlett-Packard Company, IBM Corporation, Intel Corporation, NCR Corporation, and Tandem Computers, Inc.
With the exception of Intel, these companies also plan to be distributors of Wolfpack-based clusters as soon as the software is released. Other system vendors who have announced plans to certify and offer Wolfpack clusters in 1997 include Amdahl Corporation, Siemens-Nixdorf Inc., and Stratus Computer Company. Software vendors who have publicly discussed plans for Wolfpack-enabled products include Computer Associates, Microsoft Corporation, Oracle Corporation, SAP Inc., and Vinca Corporation.
Yes. Microsoft will provide tools that allow application developers to create and manage enterprise applications that take advantage of clustering for Windows NT Server. Preliminary versions of the application programming interface (API) specifications and Software Development Kit (SDK) were published at the Microsoft Server Professional Developers Conference in November 1996. Developers are using these tools to familiarize themselves with the technology, to test their current products on Wolfpack clusters, and to begin creating cluster-aware products that will exploit Wolfpack services for higher availability, easier manageability, and greater scalability.
No. Wolfpack provides basic availability and manageability benefits for any "well behaved" server application. A "well behaved" application has the following two characteristics: (1) it maintains everything it needs to restart cleanly on a disk drive which can be accessed by another machine in the cluster, and (2) its clients can gracefully handle pauses in service of up to a minute. Most commercial applications have these two characteristics.
In general, applications must be cluster-enabled to realize the performance and scalability benefits of clusters. However, applications that build on top of cluster-aware core applications, such as large commercial database packages (for example, an accounting or financial database application on top of Microsoft SQL Server™), will benefit automatically from cluster enhancements made to the underlying application (for example, SQL Server).
No. Wolfpack does not require any special software on the client for transparent recovery of services that connect to clients via standard SMB and IP protocols, such as Web sites or Windows file shares. Clients connecting via ODBC protocols to a named server would have to be written to utilize the ODBC extension that provides a client with the name of a failover server.
Yes, each application that is part of a group must be installed on each node so that it can be started on that node during a failover.
At the time of the initial Phase 1 release, Microsoft will institute an ongoing hardware certification program to rapidly expand the number of vendors and Wolfpack-based configurations available to customers. Microsoft will also continue to work with the software industry to support their efforts to provide customers with a wide range of Wolfpack-based, cluster-aware application products.
No. Wolfpack runs on Windows NT Server, so a certified Wolfpack cluster can potentially contain any two servers that are certified to run Windows NT Server. However Wolfpack hardware certification will apply to a complete cluster configuration—two servers, an interconnect, and a storage solution—so it is unlikely that vendors will certify clusters containing servers from more than one system manufacturer.
Yes. The Wolfpack administrator’s console can be run by an authorized user from any Windows NT Workstation or Windows NT Server on the network.
Wolfpack provides true "active/active clustering," which means every machine in the cluster is available to do real work, and each machine in the cluster is also available to recover the resources and workload of any other machine in the cluster. Thus, there is no need to have a wasted, idle server standing by waiting for a failure.
Any client that can connect to Windows NT Server via TCP/IP will work with Wolfpack. Wolfpack does not require any special software on the client for transparent recovery of services that connect to clients via standard SMB and IP protocols, such as Web sites or Windows file shares. Clients connecting via ODBC protocols to a named server would have to be written to utilize the ODBC extension that provides a client with the name of a failover server.
Wolfpack software will only work with Windows NT Server. The initial version of Wolfpack will require Windows NT Server 4.0 with Service Pack 3, or later versions.
Microsoft will announce packaging for Wolfpack software near the time of its release.